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1
Desidera, Cassiane. "Blendas de poliamida reciclada e polietileno proveniente da recuperação de embalagens multicamadas". [s.n.], 2007. http://repositorio.unicamp.br/jspui/handle/REPOSIP/248790.
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Orientador: Maria Isabel FelisbertiTese (doutorado) - Universidade Estadual de Campinas, Instituto de Quimica
Made available in DSpace on 2018-08-09T13:26:12Z (GMT). No. of bitstreams: 1 Desidera_Cassiane_D.pdf: 2267266 bytes, checksum: 9f026acbcd18caa17f017b257c7f0b46 (MD5) Previous issue date: 2007
Resumo: Blendas de poliamida e polietileno são exemplos de misturas imiscíveis e incompatíveis. Entretanto, a compatibilidade pode ser alcançada adicionando-se compatibilizantes ou promovendo a mistura reativa. Neste projeto teve-se como objetivo o preparo e a caracterização de blendas de poliamida-66 reciclada (rPA-66) e diferentes polietilenos, incluindo materiais virgens e reciclados: 1) vPEBD - polietileno de baixa densidade virgem, 2) vEMAA - poli(etileno-co-ácido metacrílico) virgem, 3) rPEBD - uma mistura reciclada contendo PEBD e EMMA, e 4) PEAI - uma mistura reciclada contendo PEBD, EMMA e alumínio particulado. As blendas foram preparadas em extrusora dupla rosca e os corpos de prova, obtidos por injeção, foram caracterizados por análise dinâmico-mecânica (DMA), microscopia eletrônica de varredura (SEM), calorimetria exploratória diferencial (DSC), análise termogravimétrica (TG), espectroscopia de infravermelho com transformada de Fourier (FTIR), ensaios de solubilidade seletiva, índice de fluidez (IF) e testes mecânicos de tração e de resistência ao impacto. Foi constatada a formação de um copolímero de enxertia (PE-g-rPA66) gerado in situ durante o processamento, o qual promoveu uma maior adesão interfacial para as blendas rPA-66/vEMAA, rPA-66/rPEBD e rPA-66/PEAI em relação à blenda rPA-66/vPEBD. A degradação prévia sofrida pelos polímeros reciclados (rPEBD e PEAI) durante sua vida útil e etapas de reciclagem, mostrou ser um fator importante para a obtenção do copolímero de enxertia. Em especial, o PEAI apresenta a maior susceptibilidade à degradação devido ao efeito catalítico das partículas de alumínio, fator este que levou a maior formação do copolímero PE-g-rPA-66 em relação aos outros polietilenos. De maneira geral, as blendas apresentaram resistência ao impacto e deformação na ruptura superiores às da poliamida e estabilidade térmica superior a do polietileno
Abstract: Polyamide and polyethylene blends are examples of immiscible and incompatible systems. However, the compatibility can be reached adding compatibilizer to the system or promoting the reactive blending. The aim of this work was to prepare and characterize blends of recycled polyamide-66 (rPA-66) with different grades of polyethylenes, including virgin and recycled materials obtained from recovered multilayer packaging: 1) vLDPE - virgin low density polyethylene, 2) vEMAA - virgin ethylene-methacrylic acid copolymer (EMAA), 3) rLDPE - a recycled mixture of two polymers: LDPE and EMAA and 4) PEAI - a mixture of three materials: LDPE, EMAA and aluminum particles. The blends were prepared in a twin screw extruder and characterized by dynamic-mechanical analysis (DMA), scanning electron microscopy (SEM), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), Fourier Transformed Infra Red Spectroscopy (FTIR), solubility tests, melt flow index (MFI) and impact and tensile tests. The grafted copolymer (PE-g-rPA66) was generated in situ during the processing. This copolymer provided higher interfacial adhesion of rPA-66/EMAA, rPA-66/rLDPE and rPA-66/PEAI blends in comparison with the PA-66/vLDPE blend. The previous degradation suffered by the recycled polymers (rLDPE and PEAI) in their usefull life and the recycling stages, as well their higher susceptibility to the thermal degradation in the processing step, seems to be an important factor for obtaining the grafted copolymer (PE-g-rPA66). The aluminum particles accelerated the LDPE degradation and also improved the grafting copolymerization in comparison with others polyethylenes. In general, the blends showed higher impact strength and elongation at break that polyamide and higher thermal stability that polyethylene
Doutorado
Físico-Química
Doutor em Ciências
2
Isik, Fatma. "Nanocomposites Based On Blends Of Polyethylene". Master's thesis, METU, 2005. http://etd.lib.metu.edu.tr/upload/3/12606338/index.pdf.
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In this study the effects of compatibilizer type, organoclay type, and the addition order of components on the morphological, thermal, mechanical and flow properties of ternary nanocomposites based on low density polyethylene, LDPE were investigated. As compatibilizer, ethylene/methyl acrylate/glycidyl methacrylate, ethylene/glycidyl methacrylate, and ethylene/butyl acrylate/maleic anhydrideas organoclay Cloisite&
#61666
15A, Cloisite&
#61666
25A and Cloisite&
#61666
30B were used. All samples were prepared by a co-rotating twin screw extruder, followed by injection molding. Before producing the ternary nanocomposites, in order to determine the optimum amount of the organoclay and compatibilizer, binary mixtures of LDPE/organoclay and LDPE/compatibilizer blends with different compositions were prepared. Based on the results of the mechanical tests, compatibilizer and organoclay contents were determined as 5 wt. % and 2 wt % respectively. After that, ternary nanocomposites were prepared with each compatibilizer/organoclay system and characterization of these nanocomposites was performed. Among the investigated addition orders, mechanical test results showed that the best sequence of component addition was (PCoC), in which LDPE, compatibilizer and organoclay were simultaneously compounded in the first run of the extrusion. Considering the ternary nanocomposites, compositions of LDPE/E-MA-GMA/15A, LDPE/E-GMA/15A and LDPE/E-nBA-MAH/30B showed the highest improvement in mechanical properties. According to the DSC analysis, addition of organoclay and compatibilizer does not influence the melting behavior of the compositions and both compatibilizers and organoclay types have no nucleation activity in LDPE. In the X-Ray analysis, the highest increase of the basal spacing for ternary nanocomposites obtained for LDPE/E-BA-MAH/organoclay nanocomposites. This increase was 83 %, 198 %, and 206 % for samples containing 15A, 25A and 30B respectively.
3
Zhang, Ai Yang. "Physical property enhancement of polyethylene blends". Thesis, Brunel University, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.285090.
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Finlay, Joanna. "A study of polyolefin blends". Thesis, University of Bristol, 2003. http://hdl.handle.net/1983/765bb977-09b6-424e-970d-4c052a37f3f3.
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Hosier, Ian L. "Morphology and electrical properties of polyethylene blends". Thesis, University of Reading, 1996. https://eprints.soton.ac.uk/265714/.
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Structure-property relationships in binary polyethylene blends, and how they relate to electrical strength, have been investigated by various analytical steps. Scanning and transmission electron microscopy have been used to characterise in detail the microstructure of blends composed of linear (LPE) and branched (BPE) polyethylene, these have shown a general increase in the size of isothermally crystallised spherulites with increasing LPE content. On increasing the crystallisation temperature, spherulites became more compact and better separated, whereas on quenching, a morphology essentially independent of LPE content was obtained. Differential scanning calorimetry revealed a two phase system whose composition did not depend on LPE content. Electrical testing using an AC ramped voltage, between parallel ball bearing electrodes, was employed to characterise the electrical insulation strength of the materials. Morphological, rather than molecular factors, were found to be key at influencing the electrical strength. Electrical strength was also found to be highly sensitive to the testing procedure and sample geometry employed. From computer simulations it was found that the general patterns of tree growth depended on sample geometry, test conditions, and morphology, in a similar way to that found by experiment. The idea of dielectric failure due to a propagating damage structure is not inconsistent with the simulated or experimental data. A variety of blend systems were also subjected to mechanical tensile deformation and it was found that the morphology was affected significantly, even for small deformations within the elastic limit. Consequently, the electrical strength was reduced by mechanical tensile strain. A 16% increase in electrical strength over BPE alone, could be achieved by the use of a carefully formulated blend, which has potential for commercial exploitation.
6
Minick, Jill Suzanne. "Microstructural analysis of polyethylenes and their blends and copolymers". Case Western Reserve University School of Graduate Studies / OhioLINK, 1995. http://rave.ohiolink.edu/etdc/view?acc_num=case1058204252.
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陳仁英 i Din-eng Sy. "Reprocessing characteristics of polyethylene and its binary blends". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1996. http://hub.hku.hk/bib/B43893673.
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Rabie, Allan John. "Blends with low-density polyethylene (LDPE) and plastomers". Thesis, Stellenbosch : Stellenbosch University, 2004. http://hdl.handle.net/10019.1/49870.
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Thesis (MSc)--Stellenbosch University, 2004.ENGLISH ABSTRACT: This study describes the design, building and optimization of a fully functional preparative TREF (Prep-TREF) apparatus. This apparatus allows for the fractionation of semicrystalline polyolefins according to the crystallizability of the molecules. Various factors, such as the sample cooling rate and the effect of on-support and off-support crystallization, are investigated. The preparative TREF is used to fractionate a commercial low-density polyethylene (LOPE), two commercially available plastomers (polyethylene-l-octene copolymers), as well as blends of the LOPE and the respective plastomers. It is shown that in each case the samples fractionated by crystallizability. The fractions recovered from the Prep-TREF were characterized by CRYSTAF, OSC and NMR analysis. It is shown how the results of this preparative fractionation allow for a better understanding of the molecular heterogeneity in the LOPE and plastomers. New ways of presenting the data from the preparative fractionation, in terms of 3- dimensional plots, are also investigated. These plots offer a novel way of presenting the molecular heterogeneity in the samples in terms of the molecular crystallizability. These plots highlight features that are difficult to detect in the conventional two-dimensional plots. In conclusion, the influences of various blending ratios of LOPE and plastomer on the morphological and physical properties of the blends, such as haze, clarity, and tear-and impact strength are determined.
AFRIKAANSE OPSOMMING: Die doel van hierdie studie was die ontwikkeling en optimisering van 'n ten volle funksionerende TREF. Hierdie tegniek word gebruik om polimeermengsels te fraksioneer deur gebruik te maak van die kristaliseerbaarheid van polimere. Verskeie faktore soos die afkoel spoed en die effect van met en sonder 'n ondersteuning(seesand) vir kristaliseering was ondersoek. Hierna is navorsing gedoen om 'n beter begrip ten opsigte van die meganiese, fisiese en optiese eienskappe van lae-digtheid poliëtileen (LDPE) te ontwikkel. Hierdie LDPE is met die affiniteitsreeks plastomere van die maatskappy, Dow Chemicals, gemeng om tendense in die gefraksioneerde polimere te indentifiseer. Een van Sasol se kommersiële LDPE produkte en twee van Dow Chemicals se plastomere is individueel gefraksioneer. Die mengsel van die twee ongefraksioneerde LDPE en plastomere is nog nooit voorheen op 'n molekulêre basis ondersoek nie. Dit is in hierdie studie gedoen deur van TREF gebruik te maak. Nuwe maniere is ontwikkel om data op 'n nuwe manier voor te stel deur middel van 3 Dimensionele grafieke te skep om resultate voor te stel wat andersins baie moelilik was om voor te stel in een dimensie agv die hoeveelheid data wat geinterpreteer word. Ten slotte is die invloed van die verskillende mengverhoudings van LDPE en plastomere op die morfologiese en fisiese eienskappe soos deursigtigheid, helderheid, skeur- en impaksterkte, ook ondersoek.
9
Koliada, Maksym, Viktoriia Plavan i Bohdan Savchenko. "PROPERTIES OF COLLAGEN-BASED WASTE/POLYETHYLENE THERMOPLASTIC BLENDS". Thesis, Kaunas University of Technology, 2016. https://er.knutd.edu.ua/handle/123456789/4771.
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Sy, Din-eng. "Reprocessing characteristics of polyethylene and its binary blends". Hong Kong : University of Hong Kong, 1996. http://sunzi.lib.hku.hk/hkuto/record.jsp?B17545754.
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CRISENZA, TOMMASO ULISSE FILIPPO. "Thermoplastic elastomers from chlorinated polyethylene/nylon terpolyamide blends". Doctoral thesis, Università degli Studi di Milano-Bicocca, 2012. http://hdl.handle.net/10281/28398.
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Blends of chlorinated polyethylene (CPE) and Nylon terpolyamide (PA) were
prepared with different ratios. It is generally known that CPE has intrinsic
properties of heat, oil and oxidation resistance, so the obtained materials are well
suitable in the hose, pipe and seal industry. CPE was strengthened by a 6,6-6,12
co-polyamide with the glass transition temperature slightly above room
temperature and a particularly low melting temperature, that allowed to obtain
the blends by typical industrial processes of mixing, milling and injection
molding. Mechanical and rheological properties were investigated both with
tensile tests and dynamic mechanical analysis: the results showed that CPE and
PA form phase separated systems with excellent compatibility as the strength and
modulus were improved. The thermal and mechanical behavior of the blends is
that typical of thermoplastic elastomers. The comparison of the FTIR spectra of
the blends in respect of linear combination of those of the component polymers
allowed the detection of differences attributed to the existence of interactions at
the interface responsible of the enhanced mechanical properties. These results
were corroborated by time-domain proton NMR experiments, with an improved
method for the measurement of the hard/soft ratio in phase separated systems.
With the aim to resolve the morphology of the blends, samples were studied with
laser scanning confocal fluorescent microscopy (LSCFM). CPE rubber was
homogeneously labeled with a fluorescent dye by solution treatment and then
blended with PA in order to increase the contrast between phases in fluorescent
microscopy. Scanning Electron Microscopy and Atomic Force Microscopy
techniques were used to confirm the data collected with LSCFM. A continuous
and interpenetrating structure of the two phases is finally revealed for the blend
with the best mechanical properties.Blends with co-continuous structures may combine the properties of both
components in a favorable way. For example, a co-continuous structure leads to
the maximum contribution of the mechanical modulus from each component
simultaneously. Synergistic effects have also been shown in mechanical
properties. Constituting a stable co-continuous morphology just mixing two
polymers it is not that easy, and even more difficult is to detect such
microstructure within the bulk of the material. For these two reasons, cocontinuous
polymer blends are an interesting and challenging research topic. In
addition, these co-continuous structures offer promising opportunities for
improving properties and creating tailor-made materials.
For these reason, and also as very few examples of Thermoplastic elastomers
based on Chlorinated polyethylene and Nylon are present in the literature, the
project for this thesis came to life. This work is aimed at the achievement of a
material with thermoplastic elastomeric mechanical and processing properties,
for which the structure properties relationships would be completely understood
and explained as due to synergistic interfacial interaction between phases and cocontinuous
morphology within them.
12
Kegel, Mark. "Fibres from recycled post consumer PET/nylon 6 blends". Australasian Digital Thesis Program, 2006. http://adt.lib.swin.edu.au/public/adt-VSWT20070606.111448/index.html.
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Thesis (PhD) - Swinburne University of Technology, Industrial Research Institute Swinburne - 2006.A thesis submitted to Industrial Research Institute Swinburne in fulfilment of the requirements for the degree of Doctor of Philosophy, Swinburne University of Technology - 2006. Typescript. "July 2006". Includes bibliographical references (p. 147-156).
13
Velazquez, Omar Delgadillo. "Thermorheology and processing of polyethylene blends : macromolecular structure effects". Thesis, University of British Columbia, 2008. http://hdl.handle.net/2429/1057.
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Rheological and processing behavior of a number of linear low-density polyethylene(LLDPE)/low-density polyethylene (LDPE) blends was studied with emphasis on the effects of long chain branching. First, a linear low-density polyethylene (LL3001.32) was blended with four LDPE's having distinctly different molecular weights. At high LDPE weight fractions, DSC melting thermograms have shown three different polymer phases; two for the pure components and a third melting peak of co-crystals. Different rheological techniques were used to check the thermo rheological behavior of all blends in the melt state and the effect of long chain branching. It was found that all blends are miscible in the melt state at small LDPE concentrations. The elongational behavior of the blends was studied using a uniaxial extensional rheometer, SER. The blends exhibit strain hardening behavior at high rates of deformation even at LDPE concentrations as low as 1%, which suggests the strong effect of branching added by the LDPE component. On the other hand, shear rheology was found to be insensitive to detect addition of small levels of LDPE up to lwt%.
The second set of blends prepared and studied consisted of two Ziegler-Natta LLDPE's (LL3001.32 and Dowlex2045G) and two metallocene LLDPE's(AffinityPL1840 and Exact 3128) blended with a single LDPE. In DSC melting thermograms, it was observed that blends with metallocence LLDPE's exhibit a single melting peak at all compositions; whereas the Ziegler-Natta blends exhibit three melting peaks at certain compositions. It was found also that the metallocene LLDPE's are miscible with the LDPE at all concentrations. On the other hand, the Ziegler-Natta LLDPE's were found to be miscible with LDPE only at small LDPE concentrations.
The processing behavior of all blends with emphasis on the effects of long chain branches was also studied in capillary extrusion. The critical shear stresses for the onset of sharkskin and gross melt fracture are slightly delayed with the addition of LDPE into LLDPE. Furthermore, the amplitude of the oscillations in the stick-slip flow regime, known as oscillating melt fracture, were found to scale with the weight fraction of LDPE. Amounts as low as 1 wt% LDPE have a significant effect on the amplitude of pressure oscillations. These effects are clearly due to the presence of LCB. It is suggested that the magnitude of oscillations in the oscillating melt fracture flow regime can be used as a method capable to detect low levels of LCB.
Finally, the sharkskin and stick-slip polymer extrusion instabilities of a linear low-density polyethylene were studied as a function of the type of die geometry. The critical wall shear stress for the onset of flow instabilities, the pressure and flow rate oscillations, and the effects of geometry and operating conditions on the instabilities are presented for a LLDPE. It was found that sharkskin and stick-slip instabilities were present in the capillary and slit extrusion. However, stick-slip and sharkskin in annular extrusion are absent at high ratios of the inside to outside diameter of the annular die. This observation also explains the absence of these instabilities in polymer processing operations such as film blowing. These phenomena are explained in terms of the surface to volume ratio of the extrudates.
14
Al-Shamrani, Abdoul Ali. "Characterization, optimization and modelling of PE blends for pipe applications". Thesis, Loughborough University, 2010. https://dspace.lboro.ac.uk/2134/6019.
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Bimodal polyethylene resins are frequently used for pipe applications. In this work, blending was used to produce polyethylenes with comparable properties, particularly with respect to processing, stress crack resistance and tensile properties. Suitable blend components were identified, and their performance screened used ECHIP experimental design software. Blends were characterized using gel permeation chromatography (GPC), differential scanning calorimetry (DSC), tensile testing, stress crack resistance measurements, impact toughness testing, capillary rheometry and melt index measurements. GPC, DSC and melt index results reveal that the method of meltcompounding produced morphologically uniform blends, with different degrees of compatibility depending on the type and level of branching of blend components. Most of the blends produced showed higher crystallinity values compared to a reference bimodal resin. Binary high density polyethylene (HDPE) blends showed better stiffness and strength properties, whereas metallocene catalyzed linear low density polyethylene (mLLDPE) containing blends illustrated superior elongation and toughness properties compared to the reference polymer and other binary blends. The highest resistance to slow crack growth (SCG) was shown by low density polyethylene (LDPE) and mLLDPE containing blends due to their high branching content. The overall blend resistance to SCG or toughness can be enhanced with levels less than 20% by weight of LDPE or mLLDPE in the blend although the tensile properties are relatively unaffected at these low concentrations. The performance of blends was optimized by changing component polymers and their weight fractions, and a model to predict optimum blends was developed using the Maple code. Optimized blends showed higher branching content, comparable molecular weight, molecular weight distribution, tensile properties, viscosity and processing behaviour to the reference polymer. Optimized blend 3, in particular, encountered the same degree of shear thinning as the reference material. Better toughness and resistance to SCG were shown by the optimized blends when compared to the reference polymer.
15
Santos, Rita de Cássia dos. "Caracterização vibracional e térmica de blendas de LDPE e m-LLDPE". Universidade de São Paulo, 2005. http://www.teses.usp.br/teses/disponiveis/46/46132/tde-06032007-220909/.
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As blendas de polietileno de baixa densidade (LDPE) com o polietileno linear de baixa densidade (LLDPE) são utilizadas comercialmente com o objetivo de melhorar as propriedades finais dos produtos e o seu processamento, minimizar custos de produção tendo, como seu principal segmento, filmes para embalagens. O LLDPE utilizado neste trabalho foi sintetizado a partir do catalisador de metaloceno (m-LLDPE) que foi projetado para oferecer melhores propriedades mecânicas em relação ao LLDPE sintetizado por catalisador Ziegler-Natta. O m-LLDPE quando comparado ao LLDPE (Ziegler-Natta) apresenta resistência ao impacto do dardo quatro vezes maior e resistência ao rasgo de duas a quatro vezes maior, menor temperatura de selagem e melhor processabilidade. O LDPE tem boa processabilidade, oferece grande estabilidade ao balão durante o processo de extrusão por sopro e apresenta boas propriedades ópticas. Este trabalho reúne a caracterização térmica, vibracional e ensaios físico-químicos e mecânicos, do LDPE, m-LLDPE e as blendas de LDPE/m-LLDPE na proporção em massa de 75/25, 50/50 e 25/75. Na caracterização térmica foram utilizadas as técnicas: termogravimetria (TG), calorimetria exploratória diferencial (DSC) e análise térmica dinâmico-mecânica (DTMA). Na caracterização vibracional utilizou-se a espectroscopia fotoacústica no infravermelho (PAS-IR) e espectroscopia Raman. Foi utilizada a técnica de difração de raios-X (WAXD) para complementação dos resultados. Nos ensaios físico-químicos e mecânicos foram avaliadas as propriedades ópticas, rasgo de Elmendorf, propriedades de tração, resistência ao impacto do dardo e resistência da termossoldagem à tração. Por estas técnicas foram avaliadas as características térmicas e estruturais dos polímeros e seu comportamento nas blendas. Pela técnica de DSC foi possível verificar a imiscibilidade destas blendas. As técnicas PAS-IR, Raman e WAXD apresentam perfis espectrais semelhantes não possibilitando distinção entre as blendas de composição diferentes. Os resultados de DSC, PAS-IR e WAXD mostraram que não ocorrem mudanças significativas no grau de cristalinidade das blendas. Os ensaios de brilho 45° e opacidade mostram as boas propriedades ópticas do LDPE e suas blendas. Os ensaios mecânicos mostram que o m-LLDPE e suas blendas apresenta boas propriedades mecânicas e boa soldabilidade. Foi possível determinar a blenda que é melhor indicada para os vários segmentos do mercado de embalagens. As blendas de LDPE/m-LLDPE mais utilizadas pela indústria são as de 25/75 ou 75/25, para diferentes tipos de aplicação.Blends of low density polyethylene (LDPE) and linear low density polyethylene (LLDPE) are used commercially to improve the final properties of the products and their process, reduce the production cost having as their main segment packing film. The LLDPE used in this work was synthesized with the metallocene catalyst (m-LLDPE), which was projected to offer better mechanical properties in relation to the LLDPE synthesized by Ziegler-Natta catalyst. The m-LLDPE, when compared to the LLDPE (Ziegler-Natta) present dart impact strength four times stronger and the tearing resistance two to four times bigger, lower sealing temperature and good processability. The LDPE has good processability, offers great estability to the baloon during the process of blown extrusion and shows good optical properties. This work brings together the thermal and vibrational characterization, physical chemistry and mechanical tests, of the LDPE, m-LLDPE and the blends of LDPE/m-LLDPE in a 75/25, 50/50 and 25/75 parts by weight. In the thermal characterization several techniques were used: termogravimetry (TG), differential scanning calorimetry (DSC) and dynamic mechanical analyser (DTMA). In the vibrational characterization, the photoacoustic spectroscopy (PAS-IR) and Raman spectroscopy were used. The X-ray diffraction (WAXD) was used to complete the results. The physical chemistry and mechanical tests evaluated optical properties, Elmendorf tearing, tensile strength, dart impact strength, heat sealing strength and hot tack strength. With these techniques the thermal characterization and the polymer structure were evaluated as well as the blend behaviour. Using the DSC technique it was possible to observe that the blends are immiscible. The PAS-IR, Raman and WAXD techniques present spectral profiles not allowing a distinction between the blends with different composition. The results of DSC, PAS-IR and WAXD show that significant changes of crystallization of the blends haven\' t occurred. The gloss 45° and haze show the good optical properties of the LDPE and their blends. The mechanical tests demonstrate the good mechanical properties and soldability of the m-LLDPE and their blends. It was possible to determine the blend that best fit the different segments of the packing market. The most frequently LDPE/m-LLDPE blends used by industry are the 25/75 or 75/25, for different applications.
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Kurtulus, Ceren. "Self Reinforcement Of Poly(ethylene Terephthalate) And Polyethylene Blends". Master's thesis, METU, 2007. http://etd.lib.metu.edu.tr/upload/3/12608306/index.pdf.
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In this study, 20/80 (weight %) Poly(ethylene terephthalate) (PET) /High
Density Polyethylene (HDPE) Microfibrillar Reinforced Composites (MFC)
were prepared by using high density polyethylene (HDPE) as the matrix
material, poly(ethylene terephthalate) (PET) as the reinforcing component.
Ethylene n-butyl acrylate-glycidyl methacrylate (E-nBA-GMA) and ethylene
methyl acrylate (E-MA) as the compatibilizers in 1, 5, and 10 wt. %.
The objective of this study is to produce MFCs based on PET and HDPE via
extrusion-drawing-injection method and to characterize as extruded, as
drawn and injection molded materials in terms of morphologies, and
mechanical and thermal properties. In addition, the effect of compatibilizer
type and content on properties of PET-HDPE composites was studied. For
comparison purposes, conventional PET-HDPE composites with and without
compatibilizer were prepared. Also, the effect of screw speed and drawing
speed on the morphologies and mechanical and thermal properties were
investigated. The effect of low and high injection temperature molding on
morphologies were also observed.
SEM analyses showed that, extruded blends became oriented after drawing.
The fibrillar structure was preserved after injection molding. High injection
molding temperature destroyed the structure of PET microfibers. In addition,
it was also observed that the adhesion between HDPE and PET improved
with the addition of the compatibilizers.
Tensile strength and tensile modulus values of PET/HDPE MFCs increased
with increasing drawing speed. Increasing the screw speed resulted in a
slight decrease in tensile strength values. Addition of the compatibilizers to
the system decreased tensile strength and tensile modulus values. Results
of impact tests designated that the impact strength of the materials with and
without MFC structure increased with the increasing amounts of E-nBAGMA.
DSC analyses pointed out that, melting temperatures of HDPE and PET
phase did not change significantly with increasing drawing speed or with the
addition of the compatibilizer. As the drawing speed increased from 2.7
m/min to 6.2 m/min, degree of crystallinity of the drawn samples of the PET
phase increased.
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Yang, Yan. "Characterization of polyethylene terephthalate, cellulose acetate and their blends". Thesis, This resource online, 1994. http://scholar.lib.vt.edu/theses/available/etd-03302010-020651/.
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Steadman, Stuart Charles. "The in-situ production of polyethylene fibres from polymer blends". Thesis, Brunel University, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.277416.
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Razavi, Nouri Mohammed. "The thermal and mechanical properties of polypropolene metallocene polyethylenes and their blends". Thesis, University of Birmingham, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.269781.
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Huynh, Anh Nhut Materials Science & Engineering Faculty of Science UNSW. "Rubber-polymer blends: a thesis in polymer engineering". Awarded by:University of New South Wales. Materials Science & Engineering, 2007. http://handle.unsw.edu.au/1959.4/40833.
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This study examines composite materials prepared from ground recycled tires (tire crumb) and post-consumer recycled high density polyethylene (HDPE). An initial set of composites was prepared from as-received tire crumb and HDPE recyclate containing 040% tire crumb in 10% increments, using injection moulding. The elastic modulus and tensile strength were found to decrease linearly with increasing tire crumb content. Addition of tire crumb to recycled HDPE caused produced an immediate reduction in the strain to failure with a progressively more modest decrease as the tire crumb content was increased. The impact toughness decreased more linearly with increasing tire crumb fraction. Cross sections of the composites showed that the tire crumb particles were in intimate contact with the matrix but post mortem examination of the fracture surface of the impact test specimens indicated that the level of bonding had been poor. A second set of composites was a prepared from 10% tire crumb. The tire crumb was first given an oxidative treatment in hot aqueous copper chloride at concentrations from 0-5 wt% Cu Ch at 50 or 100??C for 6 or 12 hours. The composites were injection moulded with an addition of 0.5 wt% dicumyl peroxide (DCP). These composites showed good bonding between the tire crumb and the recycled HDPE even at concentrations of 0% of the Cu 2+ oxidation catalyst. The addition of DCP was found to substantially reduce the modulus of neat HDPE and this reduction was reflected in the modulus of the composites. It was found that the DCP concentration could be reduced to 0.02% without adversely affecting the composites.
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Barros, Natália Garrote de 1984. "Propriedades de material polimérico obtido da reciclagem de embalagens multicamadas". [s.n.], 2013. http://repositorio.unicamp.br/jspui/handle/REPOSIP/266576.
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Orientadores: João Sinézio de Carvalho Campos, Marco-Aurélio De PaoliDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Química
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Resumo: Considerando a importância da reciclagem, o presente trabalho teve como objetivo apresentar as propriedades mecânicas, térmicas e reológicas do material polimérico obtido a partir do processo de reciclagem de embalagens multicamadas constituídas de poliamida 6 (PA 6), polietileno de baixa densidade (PEBD) e polietileno de baixa densidade linear (PEBDL). Obteve-se o material polimérico processando-se em extrusora mono-rosca as embalagens com compatibilizantes (CP) de polietileno funcionalizado com anidrido maleico (PE-g-AM) e polietileno de alta densidade pósconsumo (PEADpc). As amostras foram preparadas nas composições que variam de 50 a 100% em massa de embalagem aglutinada. O melhor desempenho no ensaio de tração foi obtido com PE-g-AM. Porém, a adição deste CP nas blendas que continham o PEADpc, mostrou-se desnecessária. Os corpos de prova sem PE-g-AM apresentavam delaminações, devido à falta de compatibilidade entre os diferentes materiais. Entretanto, as propriedades de flexão das blendas com PEADpc foram melhores quando comparadas com as que continham PEAD virgem. Estes dados sugerem que grupos polares, originados na degradação oxidativa do polímero pósconsumo, reagiram com grupos polares da poliamida, promovendo melhor compatibilização. As análises de Microscopia Eletrônica de Varredura mostraram que estes compatibilizantes contribuíram para a diminuição do tamanho dos domínios da fase dispersa, resultando em uma mistura mais homogênea. As blendas que continham o polietileno virgem apresentaram um aumento na viscosidade quando o PE-g-AM foi adicionado. De acordo com as propriedades físico-químicas, estes materiais podem ser utilizados, por exemplo, em aplicações na área moveleira, lonas ou vasos
Abstract: Considering the importance of recycling, this study aimed to show mechanical, thermal and rheological properties from recycled multilayers packaging consisted of polyamide 6 (PA6), low density polyethylene (LDPE) and linear low density polyethylene (LLDPE). The polymeric material was processed in a single screw extruder. Two compatibilizers (CP) were applied: polyethylene-graft-maleic anhydride (PE-g-AM) and post-consumer high density polyethylene (PEADpc). Blends were prepared from 50 to 100% of agglutinated packaging. The best tensile properties were obtained with PE-g-AM. However, It is not necessary the addition of this CP in the blends with PEADpc. The specimens without PE-g-AM showed delamination, because of the lack of adherence of different polymeric materials contained in these blends. Nevertheless, the flexural properties of the blends with PEADpc were better than those with virgin PEAD. These results suggested that the polar groups from PEADpc, originated from oxidation process, may have reacted with polar groups from polyamide. The scanning electron microscopy showed a reduction in the size domains of the disperse phase when these CP were used. This produced a more homogeneous mixture. Other characteristic observed is that the addition of PE-g-AM in blends with virgin PEAD appears to increase the viscosity. The materials obtained can be applied, for example, in furniture in general, tarpaulins or vessels
Mestrado
Ciencia e Tecnologia de Materiais
Mestra em Engenharia Química
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Sweed, Muhamed. "Co-crystallization in polyolefin blends studied by various crystallization analysis techniques". Thesis, Link to the online version, 2006. http://hdl.handle.net/10019.1/2733.
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Steffl, Thomas. "Rheological and film blowing properties of various low density polyethylenes and their blends". [S.l.] : [s.n.], 2004. http://deposit.ddb.de/cgi-bin/dokserv?idn=972028625.
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CARMELI, ENRICO. "Crystallization behaviour of recycled polyolefins blends". Doctoral thesis, Università degli studi di Genova, 2022. http://hdl.handle.net/11567/1071022.
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A novel tailor-made thermal fractionation protocol, based on the Successive Self-nucleation
and Annealing (SSA) method, was developed to investigate the complex chemical composition of
PE/PP blends derived from recycling. The temperature regions where co-crystallization among the
blend components do not occur were assessed, enabling the development of the quantitative
method. Furthermore, a set-up for achieving Continuous Cooling Curve diagrams was designed,
and allowed to study the crystallization kinetics at processing-relevant cooling conditions of the
phases in the blends. An “inversion point” in the crystallization order of the two polymers arises
from the difference in crystallization rates between PP and PE with increasing cooling rate. Mutual
nucleating effects, found at the interface between the phases, correlate with the inversion point.
Moreover, the order of crystallization of the two polymers at low cooling rates, i.e., before the
inversion point, can be tuned by employing neat or nucleated PP. This demonstrates the importance
of knowing and controlling the type of components in recycled blends. Finally, the nature of such
nucleating effects was revealed by a novel approach for studying surface-induced crystallization in
the blends. The method consists of detecting variations in the crystallization kinetics of the
dispersed phase (PE) with changing the crystalline state of the matrix (PP) through self-nucleation.
The enhancement of crystallization kinetics of PE that was achieved when increasing the lamellar
thickness of PP, together with the very low value found for the interfacial free energy difference,
are evidence that such nucleating effects occur through epitaxial growth.
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Cheng, Hok Yan. "Morphology and mechanical properties of polystyrene/polyethylene blends and its toughening mechanism /". View Abstract or Full-Text, 2002. http://library.ust.hk/cgi/db/thesis.pl?MECH%202002%20CHENGH.
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Thesis (M. Phil.)--Hong Kong University of Science and Technology, 2002.Includes bibliographical references (leaves 93-100). Also available in electronic version. Access restricted to campus users.
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Winters, Ian Douglas. "The rheological and structural properties of blends of polyethylene with paraffin wax". Diss., Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/45833.
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This research addresses and illuminates a little understood region of miscible polymer mixtures and demonstrates a new means of separating wax from such blends. The method, termed Deformation Induced Phase Segregation potentially eliminates need of toxic processing solvents for wax removal or recovery in these types of blends.
Previous theories of polymer combinations address them exclusively as solutions or as blends, two independent classes having very different behaviors. This study provides bridge connecting these two classes by identifying crossover points between them and the behaviors exhibited therein. The blends of this form were found to be semi-miscible, forming a homogenous phase in the melt but a two-phase system in the solid, with the rheological behavior influenced by the polymer's molecular weight and architecture. It also demonstrates practical promise of this regime by introducing a mechanical compression process to separate the wax phase from such a type of blend. This process potentially permits production of ultra-high molecular weight polyethylene (UHMwPE) films and fibers by melt processing, thereby obviating need of otherwise essential but expensive and environmentally unfriendly toxic solvents.
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Silva, Bruna Louise. "Influência do agente compatibilizante PE-co-PEG nas propriedades da blenda PE/Epóxi". Universidade do Estado de Santa Catarina, 2014. http://tede.udesc.br/handle/handle/1658.
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Among polymer modifications options, is polymer blends, aim of this work was to study influence of the dispersion of rigid polymer in a thougness matrix. The blend in question used as matrix the high density polyethylene (HDPE) and as disperse phase the epoxy (DGEBA). The blend HPDE/Epoxy is immiscible, immiscible blends can be compatibilized, the compatibility has the purpose of generate a phase morphology stabilized and adequate. We chose to work as a compatibilizing copolymer polyethylene -block- poly (ethylene glycol) (PE -co- PEG), due PE- co -PEG having functional groups which can react with the epoxy. The blends were characterized by , torque rheometry , infrared spectroscopy (FTIR), differential scanning calorimetry (DSC) , nanoindentation , microhardness, scanning field effect (FEG) and transmission electron microscopy (TEM). Unable to verify by analysis of FTIR significant shift in the intensity of 913 cm-1, absorption band feature of the epoxy group, suggesting the reaction did not occur between the PEG hydroxyl of compatibilizer and the group epoxy. It was also not observed changes in torque rheometry curves, suggesting that not occurred reaction between the components blends. The results of DSC show that addition of the epoxy resulted in increasing in the crystallinity (68±1%) the best result was obtained for the blend with 10% of epoxy and 1% of compatibilizer. The technique X-ray diffraction showed that structure crystalline of HDPE was not altered whit incorporation of epoxy and PE-co-PEG, the increasing in the crystallinity degree may be associated whit crystallization kinetic of HDPE. the modulus of Young results present an analogous behavior, the addition of epoxy resulted an increasing in rigid of HDPE, the blend that showed higher crystallinity degree also present higher Young´s modulus (1,85±0,05 GPa). The same behavior was observed in the microhardness and nanohardness analysis. The analyze of fracture surface by field effect scanning electron microscopy (SEM) and transmission electron microscopy (TEM) revealed that the size of the epoxy phase is the micrometer range. The addition of compatibilizer caused better dispersion, decreases the size of the epoxy domains and improved the distribution of the dispersed phase. The results suggest that the increased crystallinity and resistance to plastic and elastic deformation is dependent on the domain size of the dispersed phase.
Entre as opções de modificações de polímeros, encontra-se a mais comum que é a obtenção de blendas poliméricas, um dos principais objetivos desse trabalho foi estudar a influência da dispersão de um polímero rígido em uma matriz tenaz. A blenda em questão utilizou como matriz o polietileno de alta densidade (PEAD) e como fase dispersa o epóxi (DGBA). A blenda PEAD/Epóxi é imiscível, blendas imiscíveis podem ser compatibilizada, a compatibilização possui a finalidade de gerar uma morfologia de fase adequada e estabilizada. Optou-se em trabalhar como compatibilizante o copolímero polietileno-bloco-poli(etilenoglicol) (PE-co-PEG), devido o PE-co-PEG ter grupos funcionais que podem reagir com o epóxi. As amostras produzidas foram caracterizadas por reometria de torque, espectroscopia no infravermelho (FTIR), calorimetria exploratória diferencial (DSC), nanoindentação, microdureza e microscopia eletrônica de varredura efeito campo (FEG) e microscopia eletrônica de transmissão (MET). Não foi possível verificar na análise de FTIR deslocamento significativo na intensidade de 913 cm-1, banda de absorção característica do grupo epoxídico, sugerindo que não ocorreu à reação entre a hidroxila do PEG do compatibilizante e o grupo epoxídico. Também não foi observadas alterações nas curvas de reometria de torque, tal fato sugere que não ocorreu nem uma reação entre os componentes da blenda. Os resultados de DSC mostram que a adição do epóxi resultou em um aumento na cristalinidade do PEAD, o melhor resultado apresentado de cristalinidade (68±1%) foi obtido para a blenda com 10% de epóxi e 1% de agente compatibilizante. A técnica de difração de raios-X mostrou que a estrutura cristalina do PEAD não foi alterada com a incorporação de epóxi e PE-co-PEG, sendo que o aumento do grau de cristalinidade pode estar relacionado com a cinética de cristalização do PEAD. Esses resultados do grau de cristalinidade são análogos ao modulo de Young, onde a adição de epóxi resultou um aumento na rigidez do PEAD, a blenda que apresentou maior grau de cristalinidade também apresentou maior rigidez (1,85±0,05 GPa). O mesmo comportamento foi analisado nos resultados de nanodureza e microdureza. A análise da superfície de fratura por microscopia eletrônica de varredura efeito campo (FEG) e microscopia eletrônica de transmissão (TEM) revelou que o tamanho da fase epoxídica encontra-se em escala micrométrica. O compatibilizante ocasionou uma melhor adesão de fases entre o PEAD/Epóxi, reduziu o tamanho dos domínios de epóxi e permitiu uma distribuição de fase epoxídica mais dispersa. Os resultados sugerem que o aumento da cristalinidade e da resistência à deformação plástica e elástica é dependente do tamanho do domínio de fase dispersa.
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Albrecht, Mirko, André Hüllmann i Michael Gehde. "Potentials and limitations of welding incompatible polymers". Institute for Engineering of Polymer Materials and Dyes, 2017. https://monarch.qucosa.de/id/qucosa%3A20880.
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Due to the wide range of properties of plastics (e.g. low density, low electrical and thermal conductivity), conventional materials will be increasingly substituted by polymers. Multifarious requirements on technical parts intensify the demand for joining processes, which ensure the reliable joining of incompatible thermoplastics. In this case, material bonded joints are approaching their limits. The present study focusses on the welding of two incompatible thermoplastic polymers (polyamide and polyethylene) by using adapted blend materials, which are compatible to both joining components. The results prove the feasibility of this method and indicate the high potential regarding the reachable joint strength. Furthermore, the study demonstrates the challenges regarding the suitable application of blend materials and deals with open scientific questions concerning their industrial usage.
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Hardman, Sarah Jean. "Synthesis and blend behaviour of multi-end capped polyethylene". Thesis, Durham University, 2011. http://etheses.dur.ac.uk/880/.
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There is an ever-growing need for polymers with specific surface properties for the production of modified materials. Recently, extremely efficient polymer surface modification has been achieved by incorporating dendritically end functionalised polymers into blends, which combine sufficient mobility, with optimal functionality, to cause dramatic changes in surface properties. This method has significant advantages over traditional coating technologies in that no additional processing step is required. It has already been established that blends of dendritically functionalised polymers have great potential in amorphous systems, but for commercial uptake similar results in semi-crystalline materials must be achieved. Polyethylene (PE) is the world’s most widely produced polymer, coming in many grades of molecular weight, branch content, and crystallinity. Semi-crystalline materials, such as PE possess excellent bulk properties, but their surfaces are notoriously difficult to functionalise except by harsh chemical treatments, or corona discharge methods. By bridging the gap between polymer science that is well understood, and polymer modification, will add value to commercially important materials. However to do this the effect that crystalline domains have on spontaneous surface segregation must be understood. Do crystalline regions exclude lower energy additives and drive them to the surface or are the additives trapped in the bulk? In this study new synthetic methodologies were developed for the preparation of fluoro-end-capped polymers with well defined multiple hydrophobic groups, via anionic polymerisation, resulting in analogues of end-functionalised LLDPE. Physical properties have been characterised using a variety of techniques, namely ion beam analysis (IBA), contact angle measurements and several neutron scattering measurements, including neutron reflectivity (NR), small angle neutron scattering (SANS) and quasi-elastic neutron scattering (QENS) and studies proved surface enrichment with fluoro-chain ends. This work has shown that blends of fluoro-polymer preferentially segregate to the air surface interface and the subsequent surface free energies of these blends were near that of polytetrafluoroethylene (measured surface energy was 8.95 mNm-2) with minimal amounts of fluorine. For example blends with 12 wt% (with respect to matrix polymer) fluorocarbon end-functionalised PE, which is equivalent to ~1% fluorocarbon, result in a measured surface energy of 8.44 mNm-2.
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Singh, Priti. "Morphology and rheology of binary blends of polypropylene and linear low density polyethylene". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape3/PQDD_0019/MQ49686.pdf.
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Conley, Mark Lewis. "Mechanistic investigations and optimizations of thermal stability in polyethylene and polyvinyl chloride blends". Diss., Georgia Institute of Technology, 2015. http://hdl.handle.net/1853/53938.
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The thermal stability of two distinct blended polymer systems was examined. A model for polyethylene was used to investigate the vulnerability of polyethylene to premature crosslinking in industrial crosslinking conditions. Careful experiments were conducted to gather evidence of the interaction between a peroxide crosslinking agent and a specific antioxidant additive. Multiple lines of evidence were combined to propose a complete mechanism of interaction between the two species. The mechanism was further tested and a hypothesis was proposed for the reduction in premature crosslinking exhibited when the two species are present in polyethylene blends. A specific aspect of the proposed mechanism warranted further investigation on its own. The acid-catalyzed degradation of the peroxide initiator was thoroughly investigated.
The thermal degradation of polyvinyl chloride was also studied. Model compounds were reacted with carboxylates to determine the relative rates of stabilization at various polymer defect sites. These model studies were combined with weight loss and color change investigations of bulk polymer systems. The knowledge gained from the model and polymer studies allowed for the proposal and examination of two novel stabilizing salt systems. The efficacy of the new stabilizers is presented.
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Steffl, Thomas [Verfasser]. "Rheological and film blowing properties of various low density polyethylenes and their blends / Thomas Steffl". Aachen : Shaker, 2004. http://d-nb.info/1170529844/34.
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Tam, Mei San. "Study of sisal fiber-reinforced polypropylene, polyethylene and polypropylene/polyethylene blend composites prepared by compression molding". access abstract and table of contents access full-text, 2005. http://libweb.cityu.edu.hk/cgi-bin/ezdb/dissert.pl?msc-ap-b21175123a.pdf.
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Thesis (M.Sc.)--City University of Hong Kong, 2005.At head of title: City University of Hong Kong, Department of Physics and Materials Science, Master of Science in materials engineering & nanotechnology dissertation. Title from title screen (viewed on Sept. 4, 2006) Includes bibliographical references.
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Moori, Tatiana Mayumi. "Desenvolvimento e caracterização de blendas de polipropileno e polietileno modificadas por radiação gama". Universidade Presbiteriana Mackenzie, 2014. http://tede.mackenzie.br/jspui/handle/tede/1340.
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In the polymer industry the blends have become an interesting alternative to the technological field, therefore, added different properties in a shorter period of polymers developing. The high consumption and low cost of polyolefins, PP and PE, were responsible for the growing interest in many researches, aimed to improve the limitations of the PP. In addition, new needs for future interests emerged elimination of matter, since these two components are the main constituents of domestic waste and plastics recycling. The immiscibility of PP and PE has been discussed, according to the method used, the system may or may not be homogeneous. The γ radiation results in the formation of very reactive intermediate elements, which, applied to the blend compatibility component influences some properties and benefits. The objective of this study was characterize the blends of PP/LDPE and PP/HDPE with different concentrations, investigating the best combination of polymers before and after γ radiation. The material was irradiated with doses of 30kGy, 50kGy, 100kGy and 200kGy, at a fixed rate of 11.6 kGy/h and subsequently performed the tests of mechanical and thermomechanical resistance in order to observe its effects. It concluded that the changes were directly related to the factors: dose and concentration. For each type of combined, there was a specific result. The ionizing radiation change the compatibility of the components, promoting some properties of the blends, showing strong and economical materials.
No setor polimérico as blendas passaram a ser uma interessante alternativa para o campo tecnológico, pois, agregaram propriedades de polímeros distintos em um menor prazo de desenvolvimento. O alto consumo e baixo custo das poliolefinas, PP e PE, foram responsáveis pelo crescente interesse em diversas pesquisas, almejando melhoria as limitações do PP. Além disso, novos interesses surgiram pelas necessidades futuras de eliminação da matéria, uma vez que estes dois componentes são os principais constituintes dos resíduos domésticos de plástico e de reciclagem. A imiscibilidade do PP e PE foi bastante discutida, pois, de acordo com o método de ensaio utilizado, o sistema pode ou não ser homogêneo. A radiação γ proporciona a formação de elementos intermediários muito reativos, do qual, aplicadas nas blendas influencia na compatibilidade dos componentes e beneficia algumas propriedades. Assim, o objetivo desse trabalho foi caracterizar as blendas de PP/PEBD e PP/PEAD com diferentes concentrações, investigando a melhor combinação dos polímeros antes e após a radiação γ. O material foi irradiado com doses de 30kGy; 50kGy; 100kGy e 200kGy, numa taxa fixa de 11,6 kGy/h e, posteriormente, realizou ensaios de resistência mecânica e termomecânica a fim de observar seus efeitos. Concluiu-se que as modificações ocorridas estavam, diretamente relacionadas aos fatores: dose e concentração. Para cada tipo de combinação observou-se um resultado específico. A radiação ionizante alterou a compatibilidade dos componentes, favorecendo algumas propriedades das blendas, revelando materiais resistentes e de baixo custo.
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Santos, C?ssia Thais Silva. "Obten??o de blendas polim?ricas a partir da reciclagem de sucatas de aparelhos celulares e polietileno de baixa densidade reciclado". Universidade Federal Rural do Rio de Janeiro, 2016. https://tede.ufrrj.br/jspui/handle/jspui/1736.
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It is crescent the research by new materials and methods for creating and same market insertion. Currently, among the various types of waste, electronic waste is considered obsolete in a very short time and require proper disposal. In Brazil, the last year, the reuse of plastic materials has increased. This study aimed to research the importance of mobile phones waste recycling, which have short pace of useful life used as reinforcements, no development of new materials containing recycled thermoplastic polymer (Low Density Polyethylene LDPE) and from the analyzes mechanical and dangerousness of these new materials, so justify the replacement of the importance of some materials with longer life time and easy recyclability, that form provides a reduction of environmental impacts caused by the generated waste were developed six blends of (Low Density Polyethylene recycled and PCABS carcasses - LDPErec/PC-ABS), with composition and grain size variation of cell granulometry housing and also an analysis of pure materials. The results obtained for analysis of diffraction X-ray, density, water absorption, hardness, scanning electronic microscopy and mechanical testing showed one low interaction between polymers, beyond the performance of the amorphous polymer morphology and hence the crystallinity mix, directly affected at the thermal and mechanical properties. As for the hazard analysis of the materials developed, they were not found excess levels of metal toxicants, the limits established by ABNT NBR 10004
? crescente a pesquisa por novos materiais e metodologias para a cria??o e inser??o dos mesmos no mercado. Atualmente, dentre os diversos tipos de res?duos, os res?duos eletroeletr?nicos tem aumentado exponencialmente, pois estes tem sido considerados obsoletos em um intervalo de tempo muito curto e necessitam de descarte adequado. No Brasil, nos ?ltimos anos, o reaproveitamento de materiais pl?sticos tamb?m tem aumentado. Neste contexto, este trabalho teve como objetivo pesquisar a import?ncia da reciclagem de res?duos de telefones celulares (carca?as), que possuem curto tempo de vida ?til, utilizados como refor?os, no desenvolvimento de novos materiais, contendo pol?mero termopl?stico reciclado (polietileno de baixa densidade ? PEBD) e, a partir das an?lises mec?nicas e da periculosidade destes novos materiais, justificar a import?ncia da substitui??o de alguns materiais por outros com maior tempo de vida ?til e de f?cil reciclabilidade, de forma que proporcione a redu??o dos impactos ambientais provocados com os res?duos gerados. Para tal, foram desenvolvidas 6 blendas de (Polietileno de baixa densidade reciclado e carca?as de PC-ABS - PEBDrec/PC-ABS), com varia??o da composi??o e granulometria das carca?as de aparelhos celular, e tamb?m a an?lise dos mat?rias puros. Os resultados obtidos pelas an?lises de difra??o de raios-X, densidade, absor??o de ?gua, dureza, microscopia eletr?nica de varredura e ensaios mec?nicos mostraram que a baixa intera??o entre os pol?meros, al?m da atua??o do pol?mero amorfo na morfologia e, consequentemente, na cristalinidade da mistura, afetou diretamente nas propriedades t?rmicas e mec?nicas. Quanto ? an?lise de periculosidade dos materiais desenvolvidos, n?o foram encontrados n?veis excedentes de metais t?xicos, conforme limites estabelecidos pela NBR ABNT 10004.
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Yilmaz, Gokhun. "Effects Of Titanate Coupling Agents On Low Density Polyethylene And Polypropylene Blends And Composites". Master's thesis, METU, 2008. http://etd.lib.metu.edu.tr/upload/12610135/index.pdf.
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The objective of this study is to investigate the effects of titanate coupling agents on low density polyethylene (LDPE) and polypropylene (PP) blends and composites in terms of their mechanical and morphological properties. PP and LDPE composites were produced separately in a Brabender internal mixer, and CaCO3 was used as inorganic filler with compositions of 20, 40 and 60 %. PP/LDPE blends were produced in a twin-screw extruder with ratios of 75/25, 50/50 and 25/75. Their composites were prepared with addition of untreated and titanate-treated CaCO3 at 20% filler content.
Titanate coupling agent which is appropriate for LDPE, PP and CaCO3 was used to improve the mechanical properties of the blends and composites. For this purpose, &ldquoLica 12&rdquo
which is a kind of neoalkoxy organotitanate was used. Two forms of Lica 12 were used: powder form (Capow L12) and pellet form (Caps L12). Samples with and without titanate were prepared and then they were injection molded to make specimens for tensile and impact tests. Tensile fracture surfaces of samples were examined by scanning electron microscopy (SEM). Their mechanical and morphological properties were compared with each other to determine the effects of Lica 12. This study showed that Capow L12 improved strain at break and impact strength of PP/CaCO3 composites and PP/LDPE blends containing 75% and 50% PP. The strain at break value of of PP75 composite with 20% titanate-treated filler increased significantly up to 509% which is the highest value among all blends and composites in this study. Capow L12 exhibited its functions in PP matrix much more effectively than in LDPE matrix.
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Argoud, Alexandra. "Control and stabilization of morphologies in reactively compatibilized Polyamide 6 / High Density Polyethylene blends". Phd thesis, Université Claude Bernard - Lyon I, 2011. http://tel.archives-ouvertes.fr/tel-00835910.
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This study deals with reactively compatibilized Polyamide 6 / High Density Polyethylene blends. More precisely, it focuses on the relationship between (1) the formulation, the processing parameters in corotating twin screw extrusion and (2) the morphologies and the microstructures of blends. Multi-scale morphologies were observed by Scanning and Transmission Electron Microscopy. At the micron scale, the following morphologies were developed: nodular dispersions, stretched nodules and co-continuous morphology. As the processing conditions did not influence the types of morphology, the different morphological regions were reported in ternary diagrams. In the case of compatibilized blends, two mechanisms for morphology development have been proposed: (1) the compatibilization reaction, being very fast, leads to the formation of nano-dispersions by interfacial instabilities and (2) the standard break-up/coalescence mechanism of domains poor in copolymer could lead to the formation of morphologies up to the micron scale. Both the evolution of the largest size as a function of the composition and the distribution of sizes were modeled using percolation concepts. The stability of the morphologies was then studied either during static annealing or controlled shear or in a second step processing. The copolymer formed at the interface allows stabilizing the size of the morphologies. Finally, crystallization at lower temperature was observed by Differential Scanning Calorimetry when the polymers are confined in submicron domains.
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Greenway, Giles R. "The effect of processing conditions on the morphology and electric strength of polyethylene blends". Thesis, University of Reading, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.339954.
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Épinat, Chloé. "Morphology development and rheological properties of reactively compatibilized Polyamide 6 / High Density Polyethylene blends". Thesis, Lyon 1, 2014. http://www.theses.fr/2014LYO10317/document.
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L'enjeu de ce travail est de comprendre les paramètres contrôlant les mécanismes de développement des morphologies et notamment la formation des nanodispersions pour des mélanges binaires de polyamides 6 de différentes masses molaires et de polyéthylène haute densité greffé anhydride maléique, mis en oeuvre par extrusion réactive. Le choix stratégique des matériaux a permis de balayer une large gamme de rapports de viscosité ainsi que différentes architectures de copolymères formés à l'interface. Les mécanismes de nature rhéologique ont été isolés méthodiquement des mécanismes dus à la réaction à l'interface en étudiant, d'une part, des mélanges non compatibilisés PA6/PEHD, puis l'effet de la réaction de compatibilisation seule en condition statique. Différents mécanismes de rupture de gouttes basés sur des instabilités capillaires sont proposés selon le rapport de viscosité. L'observation de microstructures ordonnées de copolymères aux interfaces en condition statique démontre la déstabilisation de l'interface fortement relié à la symétrie des copolymères formés. Les propriétés rhéologiques des mélanges sont étudiées ensuite. Les mécanismes de relaxation observés sont discutés, en particulier ceux liés aux interfaces et aux interactions entre nodules, en lien avec les morphologies des mélanges. Dans les mélanges compatibilisés, le comportement type gel ou solide-élastique (forte augmentation de l'élasticité aux basses fréquences), pour les mélanges concentrés, suggère la création d'un réseau percolant d'interactions entre nodules voisins. Enfin, un modèle performant de prédiction de la composition à l'inversion de phase à partir du comportement rhéologique est proposéThe aim of this work is to understand the parameters that control the morphology development mechanisms, and especially, the formation of nanodispersions. This study deals with binary blends of polyamide 6 of different molecular weights and maleic anhydride grafted high density polyethylene, processed by reactive extrusion. The strategic choice of blend components allowed to cover a wide range of viscosity ratio and various copolymer architectures formed at the interface. Mechanisms controlled by classical rheological laws were methodically isolated from mechanisms specific to the compatibilization reaction at the interface by studying, on the one hand, uncompatibilized PA6/HDPE blends, and on the other hand, the effect of the compatibilization reaction in static condition. Different drop break-up mechanisms based on capillary instabilities are proposed depending on viscosity ratios. The observation of ordered microphase separated copolymer domains at the interfaces in static condition attests of the spontaneous interface destabilization, strongly related to the copolymer asymmetry. Blends rheological properties are then studied. The different relaxation mechanisms obtained are discussed, especially those related to the interfaces and interactions between droplets, relatively to blends morphologies. In compatibilized blends, gel-like or solid-elastic behavior (strong elasticity increase at low frequencies) for concentrated blends, suggest the creation of a percolating network of interactions between neighboring droplets. Finally, an efficient model for predicting the phase inversion composition from the rheological behavior is proposed
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Miguel, Oládio Dias. "Blendas de amido termoplástico e polietileno grafitizado (enxertado)". Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/18/18158/tde-10112014-204204/.
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O amido termoplástico (TPS) é um material biodegradável que tem sido bastante estudado em função do seu baixo custo e pelo fato de ser derivado de fontes renováveis. Contudo, o TPS apresenta limitações mesmo para aplicação em produtos de baixos requisitos devido a conjunto de fatores como sua baixa propriedade mecânica, térmica, e de resistência à umidade, além de possuir baixa compatibilidade com outros polímeros sintéticos. Nesse trabalho foi testada a modificações do TPS com ácido cítrico e com 4,4-difenil metano diisocianato (MDI) e as blendas desses materiais com polietileno de baixa densidade (PEBD) e o efeito da modificação do PE com anidrido maleico (MA) e da adição de ceras de polietileno não modificada e modificada com anidrido maleico como agente compatibilizante. A modificação do amido com ácido cítrico e com MDI não afetou de forma significativa a sua hidrofilicidade. O uso de MDI se mostrou eficaz na melhoria das propriedades mecânicas do amido não modificado com AC. A compatibilização com cera se mostrou extremamente promissora, tendo no caso da blenda 50/50 de polietileno e TPS compatibilizada com 5 % de cera resultando em um composto com propriedades mecânicas (módulo e resistência à tração) muito similares às do polietileno de origem.Thermoplastic starch (TPS) is a biodegradable material that has been extensively studied due to its low cost and because it is derived from renewable sources. However, TPS present several drawbacks even for application in products of low performance due to its poor mechanical properties, thermal properties and moisture resistance, and also due to its low compatibility with other synthetic polymers. In this work we studied the modification of TPS with citric acid and with 4,4 \'- diphenyl methane diisocyanate (MDI) and the blends of these materials with low density polyethylene (LDPE) and the effect of modification of PE with maleic anhydride (MA) and the addition of polyethylene waxes unmodified and modified with maleic anhydride as compatibilizing agent. The modification of starch with citric acid and MDI did not affect significantly its hydrophilicity. The use of MDI is effective in improving mechanical properties of unmodified starch with AC. The compatibility with wax showed very promising with the case of blend 50/50 TPS and polyethylene compatibilized with 5% wax results in a material with mechanical properties very similar to those of polyethylene (modulus and tensile strength) .
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ARAÚJO, Jeane Paulino de. "Avaliação da reatividade entre o Biopolímero poli (Ácido Lático) (PLA) e o polietileno enxertado com ácido acrílico (PEgAA) e do efeito da concentração de PEgAA nas propriedades e na morfologia da blenda PLA/PEgAA". Universidade Federal de Campina Grande, 2018. http://dspace.sti.ufcg.edu.br:8080/jspui/handle/riufcg/1059.
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Capes
O poli(ácido lático) (PLA) tem despertado grande interesse tanto da academia como da indústria devido principalmente a sua biodegradabilidade, algumas propriedades mecânicas atraentes e por ser sintetizado a partir de matéria-prima de fontes renováveis. Entretanto, o PLA apresenta algumas desvantagens, como alta fragilidade, baixa taxa de cristalização, sensibilidade a umidade e a degradação em altas temperaturas, que limitam suas aplicações e comprometem seu processamento e desempenho final, sendo necessário muitas vezes modificar o PLA para que este possa atender as expectativas de mercado. Desse modo, foi realizada a modificação do PLA através de blendas com o polietileno enxertado com ácido acrílico (PEgAA), sendo avaliada a reatividade entre os grupos funcionais dos dois polímeros e o efeito de diferentes concentrações do copolímero PEgAA nas propriedades das blendas. As blendas PLA/PEgAA contendo 5, 10, 15 e 20% (em massa) do PEgAA foram preparados em uma extrusora dupla-rosca corrotacional, sendo caracterizadas por espectroscopia na região do infravermelho com transformada de Fourier (FTIR), calorimetria exploratória diferencial (DSC), análise térmica dinâmico-mecânica (DMTA), propriedades mecânicas, microscopia eletrônica de varredura (MEV), difratometria de raios X (DRX) e ensaios reológicos. A análise por FTIR indicou a ocorrência de uma reação de poliesterificação entre os grupos hidroxila do PLA e os grupos carboxila do PEgAA. As análises DSC e DMTA indicaram que a adição do PEgAA levou à diminuição tanto da temperatura de transição vítrea (Tg) como da temperatura de cristalização a frio (Tcc) do PLA nas blendas. Com o aumento do teor de PEgAA nas blendas houve aumento do tamanho dos domínios de PEgAA. Com a incorporação do PEgAA houve ligeiro aumento da resistência ao impacto para as blendas com 5 e 10% do PEgAA em relação ao PLA puro. A blenda PLA/PEgAA contendo 15% do PEgAA apresentou maior viscosidade complexa e o módulo de armazenamento a baixas frequências.
The poly(lactic acid) (PLA) has attracted great interest from both academia and industry mainly due to its biodegradability, some attractive mechanical properties and because it is synthesized from raw materials from renewable sources. However, PLA has some drawbacks such as high brittleness, low crystallization rate, sensitivity to moisture, and deterioration at high temperatures, which limit its applications and compromise its processing and final performance, needing to be modified, so it can meet market expectations. Thus, the modification of PLA was carried by blending it with polyethylene grafted with acrylic acid (PEgAA), assessing the reactivity between the functional groups of the two polymers and the effect of different PEgAA copolymer content on the properties of PLA/PEgAA blend. PLA/PEgAA blends containing 5, 10, 15 and 20% (wt) of PEgAA were prepared in a co-rotational twinscrew extruder, and characterized by Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), dynamic mechanical thermal analysis (DMTA), mechanical properties, scanning electron microscopy (SEM), X-ray diffraction (XRD) and rheological measurements. FTIR results indicated that a polyesterification reaction between the hydroxyl groups of PLA and the carboxyl groups of PEgAA has occurred. DSC and DMTA analyses indicated that the addition of PEgAA to PLA led to the decrease in both the glass transition (Tg) and the cold crystallization (Tcc) temperatures. The PEgAA domains size increased with the increase in the PEgAA content. With the addition of PEgAA there was a slight increase in the impact strength of the blends containing 5 and 10% of PEgAA, when compared to that of neat PLA. The PLA/PEgAA blend containing 15% (wt) of PEgAA presented the highest complex viscosity and storage modulus at low frequencies.
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Hale, Wesley Raymond. "Reactive compatibilization of PBT/ABS blends by methyl methacrylate, glycidyl methacrylate, ethyl acrylate terpolymers /". Digital version accessible at:, 1998. http://wwwlib.umi.com/cr/utexas/main.
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Dogan, Erkan. "Ter Blend Of Poly (ethylene Terephthalate), Polypropylene And Low Density Polyethylene". Master's thesis, METU, 2003. http://etd.lib.metu.edu.tr/upload/4/1045574/index.pdf.
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This study covers the recycling of waste poly(ethylene terephthalate) (PET) bottles through melt blending with low density polyethylene (LDPE) and polypropylene (PP). In general, polymer blends are known to be immiscible and incompatible with poor mechanical properties. This problem is due to the low intermolecular forces between the components of the immiscible blends. In order to enhance the interaction and compatibility between these matrices, some reactive or non-reactive copolymers were used. In this workPET was treated with silane coupling agent (SCA) (low molecular weight reactive additive) for compatilization of LDPE-PP-PET blends. LDPE-PP-PET blends were prepared in different compositions (by weight) with and without silane coupling agent at high temperatures by a single screw extrusion and injection molding. Mechanical properties of treated and non-treated blends were studied in terms of tensile strength, strain at break and impact strength. Melt flow properties of blends were investigated by melt flow index. The impact fractured surfaces and thermal behaviour of the blends were examined with Scanning Electron Microscope (SEM) and Differential Scanning Calorimeter (DSC), respectively. Through out the studies, good adhesion between PET and LDPE-PP matrix was successfully achieved by the surface treatment of PET particles. The adhesion was also observed in SEM studies. Also the variation in mechanical properties was found to be highly dependent on the number of extrusion.
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Bernard, Sophie. "Blends of a polystyrene-block-poly(ethylene oxide) copolymer and its corresponding homopolymers at the air-water interface". [Gainesville, Fla.] : University of Florida, 2006. http://purl.fcla.edu/fcla/etd/UFE0012780.
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Moreno, Diego David Pinzon. "Blendas de rejeitos pós-industriais de filmes multicamadas de polietileno de baixa densidade (PEBD) e poliamida (PA6)". Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/97/97134/tde-19092016-110402/.
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A reciclagem de resíduos sólidos tem se tornado cada vez mais relevante devido a alguns fatores como os impactos ambientais ocasionados com o seu descarte inadequado, ao rigor crescente de legislação específica e ao custo elevado para o gerenciamento apropriado destes resíduos. Na área de materiais poliméricos, os resíduos poliméricos podem ser de origem pósconsumo ou pós-industrial. Alguns rejeitos industriais poliméricos possuem características estruturais ou químicas que impossibilitam o seu reaproveitamento direto no processo que o gerou, como é o caso filmes multicamadas de polietileno de baixa densidade (PEBD) com poliamida 6 (PA6), usados para a produção de embalagens. O presente trabalho teve como objetivo central o reaproveitamento de rejeitos de filmes multicamadas de PEBD com PA6 na forma de blendas recicladas destes polímeros, fazendo uso de agente compatibilizante e variação na composição das blendas com a incorporação de PA6 virgem, a fim de produzir materiais com propriedades adequadas e custo compatível para a aplicação comercial. O desenvolvimento experimental foi dividido em três etapas que consistiram na avaliação do teor mais adequado de agente compatibilizante de fases da blenda (etapa 1), na determinação do comportamento das propriedades das blendas não compatibilizadas em diferentes composições de rejeito do filme multicamada e PA6 virgem (etapa 2) e na associação do uso de compatibilizante com variação das composições das blendas (etapa 3). A partir da execução experimental das atividades das etapas 1 e 2 do trabalho foi possível determinar que o teor de 2,5% do agente compatibilizante polietileno grafitizado com anidrido maleico (PEg- AM) é o mais adequado para compatibilizar as blendas poliméricas e que a maioria das suas propriedades das blendas apresentam um comportamento próximo ao aditivo linear, que leva em consideração somente as propriedades iniciais dos componentes poliméricos PEBD e PA6 isolados. Os diversos materiais gerados no desenvolvimento desta pesquisa apresentam desempenho de propriedades e custo de produção variáveis em função do teor de PA6 nas blendas, que podem viabilizar o uso deste material reciclado em aplicações comerciais específicas.Recycling of solid waste has been an important issue due to some factors such as environmental damage caused by inappropriate discards, increasing rigor of specific legislation and high cost to the appropriate management of these waste. Polymeric waste can be originated from post-consume or post-industrial sources. Some polymeric waste have chemical or structural characteristics that difficult their direct reuse in the same productive process such as multilayer film of low density polyethylene (LDPE) and polyamide 6 (PA6), which are used for packing. The aim of this work has been the study the mechanical recycling of multilayer films of PEBD and PA6 as PEBD/PA6 blends with adequate properties and compatible cost for commercial applications. The experimental development has been performed in 3 steps, which correspond to evaluation of more adequate content of compatibilizer agent for interface of blends (step 1), determination of behavior of the properties of blends without compatibilizer agent on different compositions of waste form multilayer films (step 2) and production of blends with compatibilizer agent graphitized polyethylene with maleic anhydride (PE-g-MA) (step 3). Has been verified that the content of 2.5% of PE-g-MA is more adequate to be used in the compatibilization of recycled PEBD/PA blends and that the performance of the blends dependents of the content of PA6 in the material. The recycled materials have potential for commercial applications.
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Wong, Tsun Wah. "A study on mechanical properties of high density polyethylene/polystyrene/SBES [i.e. SEBS] polymer blends". access abstract and table of contents access full-text, 2001. http://libweb.cityu.edu.hk/cgi-bin/ezdb/dissert.pl?msc-ap-b21175202a.pdf.
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Thesis (M.Sc.)--City University of Hong Kong, 2001."A dissertation submitted in part-fulfilment of the requirements for the degree of Master of Science of City University of Hong Kong." Title from title screen (viewed on Sept. 4, 2006) Includes bibliographical references.
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Morgan, Robert Llewelyn. "A study of the phase behaviour of polyethylene blends and the crystallization of n-alkanes". Thesis, University of Bristol, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.387994.
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Bin, Rusayyis Mohammed A. "SEBS-COMPATIBILIZED HIGH DENSITY POLYETHYLENE/POLYPHENYLENE ETHER BLENDS: A STUDY OF THEIR PROPERTIES AND MORPHOLOGIES". Case Western Reserve University School of Graduate Studies / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=case1525168988052769.
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Coelho, Paulo Henrique da Silva Leite 1985. "Estudo do efeito de compatibilização de argilas organofílicas em blendas imiscíveis de poliamida 6 e polietileno de baixa densidade". [s.n.], 2010. http://repositorio.unicamp.br/jspui/handle/REPOSIP/266910.
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Orientador: Ana Rita MoralesDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Química
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Resumo: O trabalho descreve a obtenção de nanocompósitos de polietileno de baixa densidade, poliamida 6, polietileno enxertado com anidrido maleico e montmorilonita organofilicamente modificada com o objetivo de estudar o efeito de compatibilização da argila organofílica nas blendas de polietileno e poliamida. Os compostos foram preparados pelo método de intercalação do fundido em extrusora dupla-rosca e os corpos de prova, obtidos por injeção, foram caracterizados por análise térmica dinâmico-mecânica, microscopia eletrônica de varredura, difração de raios-X, microscopia eletrônica de transmissão, calorimetria exploratória diferencial, análise termogravimétrica e teste mecânicos de resistência a tração e ao impacto. As análises térmicas revelaram uma ligeira queda da estabilidade térmica associada ao efeito de degradação do modificador encontrado na argila; o aparecimento de um novo pico de fusão nas curvas de DSC dos nanocompósitos foi associado à formação de uma nova fase cristalina na poliamida 6, causado pela presença da argila. As análises morfológicas revelaram uma adequada homogeneidade nos nanocompósitos e uma redução dos tamanhos dos domínios das duas fases da blenda, de forma que nenhum aglomerado foi observado, o que mostra que houve uma boa dispersão da argila na matriz. As análises estruturais confirmaram esta boa dispersão através da microscopia eletrônica de transmissão (MET) e da difração de raios-X (DRX), que revelaram que a argila teve suas camadas parcialmente intercaladas e/ou esfoliadas em todos os nanocompósitos estudados, e que esta estrutura encontrada proporcionou uma melhora significativa nas propriedades mecânicas dos compostos
Abstract: This work describes the behavior of nanocomposites of polyamide 6 (PA6), low density polyethylene (LDPE) and an organophilic montmorillonite. The compatibilization effect of the orgalophilic clay was studied with and without the presence of a maleic anhydride grafted polyethylene (PE-g-MA). The nanocomposites were prepared by melt intercalation on a twin screw extruder. The samples were prepared by injection molding, and characterized using scanning electron microscopy (SEM), wide-angle X-diffraction (WAXD), dynamic mechanical analysis (DMA), transmission electron microscopy (TEM) and differential scanning calorimeter (DSC). Mechanical properties as tensile strength and impact strength were also evaluated. The thermal analysis showed a slight decrease in thermal stability that was associated with the effect of degradation of the modifier of the clay; the emergence a new melting peak for the Polyamide 6 associated to a new crystalline phase due the clay nucleation effect. The morphologic analysis showed two phases for all systems but a reduction on the particle dimension due the presence of the clay, with low differences by the use of the compatibilizer. Structural analysis confirmed by transmission electron microscopy (TEM) and X-ray diffraction (XRD), which had its clay layers extensive exfoliated, with some small degree of intercalation nanocomposites at all, and that this structure has provided a significant improvement in mechanical properties of compounds
Mestrado
Ciencia e Tecnologia de Materiais
Mestre em Engenharia Química
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Ahani, M., M. Khatibzadeh, M. Mohseni, M. Vajar i S. H. Kordbacheh. "Blends of Polyethylene Terephthalate (PET) and Nanostructured Hyperbranched Polyesteramide for Improvement the Dyeability of PET: Thermodynamics". Thesis, Sumy State University, 2013. http://essuir.sumdu.edu.ua/handle/123456789/35420.
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Incorporating Hybrane H1500 as a nanostructured hyperbranched polyesteramide into polyethylene terephthalate (PET) enhances the dyeability of PET with C.I. Disperse Blue 56. The results show that the disperse dye display much greater substantivity toward the modified PET sheets compared to virgin PET one. DSC tests show that the crystallinity of modified PET sheets has slightly decreased. The main pur-pose of this work was to determine the dyeing mechanism of disperse dye on the modified PET using hy-perbranched polyesteramide by study the adsorption properties in the infinite dyebath at different tem-peratures. In fact, a few of the thermodynamic parameters of dyeing such as the equilibrium adsorption isotherm, standard affinity, enthalpy and entropy changes were studied. The bath containing virgin PET displays the highest negative values of the enthalpy change and entropy change, while the bath containing the modified PET with 2 wt% hyperbranched polyesteramide shows the lowest negative values of them.
When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/35420