Dissertations / Theses on the topic 'Blown film'
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Strater, Kurt F. "Countercurrent cooling of blown film." Thesis, McGill University, 1985. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=66003.
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Majumder, Khokan Kanti, and khokankanti@yahoo com. "Blown Film Extrusion: Experimental, Modelling and Numerical Study." RMIT University. Civil, Environmental and Chemical Engineering, 2008. http://adt.lib.rmit.edu.au/adt/public/adt-VIT20080509.161859.
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Abstract This thesis correlates rheological data into a non-linear blown film model that describes the stress and cooling-induced morphological transformations in the axial and flow profiles of the blown films. This will help to improve the physical and mechanical properties of the films in a cost effective way, which will in turn be of great benefit to the food and packaging industries. In this research, experimental and numerical studies of a blown film extrusion were carried out using two different low-density polyethylenes (LDPEs). In the experiment, the key parameters measured and analysed were molecular, rheological and crystalline properties of the LDPEs. In the numerical study, blown film simulation was carried out to determine the bubble characteristics and freeze line height (FLH). A new rheological constitutive equation was developed by combining the Hookean model with the well known Phan-Thien and Tanner (PTT) model to permit a more accurate viscoelastic behaviour of the material. For experimental verification of the simulation results, resins were processed in a blown film extrusion pilot plant using identical die temperatures and cooling rates as used in the simulation study. Molecular characteristics of both LDPEs were compared in terms of their processing benefit in the film blowing process. Based on the experimental investigation, it was found that molecular weight and its distribution, degree of long chain branching and cooling rate play an important role on melt rheology, molecular orientation, blown film processability, film crystallinity and film properties. Effect of short chain branching was found insignificant for both LDPEs. Statistical analysis was carried out using MINITAB-14 software with a confidence level of 95% to determine the effect of process variables (such as die temperature and cooling rate) on the film properties. Film properties of the LDPEs were found to vary with their molecular properties and the process variables used. Blown film model performance based on the newly established PTT-Hookean model was compared with that based on the Kelvin model. Justification of the use of PTT-Hookean model is also reported here using two different material properties. From the simulation study, it has been found that predictions of the blown film characteristics conformed very well to the experimental data of this research and previous studies using different materials and different die geometries. Long chain branching has been found as the most prominent molecular parameter for both LDPEs affecting melt rheology and hence the processability. Die temperature and cooling rate have been observed to provide similar effect on the tear strength and shrinkage properties of blown film for both LDPEs. In comparison to the Kelvin model, the PTT-Hookean model is better suited for the modelling of the film blowing process. It has also been demonstrated in this study that the PTT-Hookean model conformed well to the experimental data near the freeze line height and is suitable for materials of lower melt elasticity and relaxation time.
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Godshall, David Leonard. "Investigations of Structure–Property Relationships in Semicrystalline Thermoplastic Polymers: Blown Polyethylene Films and Polyacrylonitrile Copolymers." Diss., Virginia Tech, 2002. http://hdl.handle.net/10919/25971.
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Blown films of high molecular weight high density polyethylene (HMW-HDPE) were produced from two resins of differing molecular weight (MW) and molecular weight distribution (MWD) using a high stalk bubble configuration. The processing conditions were varied such that three film gauges, each fabricated at three frost line heights (FLH), were produced. Crystalline orientation and tear resistance properties of the films were measured. Under appropriate conditions, the formation of two populations of lamellar stacks with their surface normals orthogonal to one another were observed. Increasing the FLH increased the amount of transverse direction (TD) stacked lamellae. This finding was related to bubble shape and relaxation behavior. Balanced in plane crystalline orientation was noted to give the best dart impact performance. Interestingly, for the lower Mw resin in the study, this could be achieved by down gauging.
In a second project, structure-property-processing relationships were investigated in a series of high density polyethylene (HDPE) blown films. The use of metallocene and chromium oxide based resins allowed the effects of MW and MWD on orientation behavior to be studied. All films possessed Keller-Machin low stress morphologies oriented along the film MD. Under identical processing conditions, the narrower MWD resins produced films with greater orientation than the broader MWD resins of equivalent weight average MW. Greater processing stresses and shorter quench times were noted to produce higher levels of orientation. Moisture vapor transmission rate (MVTR) performance of these films was also measured. Orientation effects were seen to influence MVTR as permeation behavior did not scale directly with the crystalline content in the films.
Additional studies investigated the relationship between comonomer content and the thermal and structural properties of novel poly(acrylonitrile-co-methyl acrylate) materials. Five polymers were studied with methyl acrylate (MA) content varying between 0 and 15 mol%. The MA decreased both the glass transition and melting temperatures. Melting point depression was sufficient in the two highest MA content copolymers to allow for complete melting prior to the onset of thermal degradation using modest heating rates (20 ºC/min). Insight into the heterogeneous structure of poly(acrylonitrile) homopolymer was gained through both conventional and modulated differential scanning calorimetry.Ph. D.
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Gururajan, Giriprasath. "Real-time Raman spectroscopy and wide-angle x-ray diffraction during single-layer and multi-layer blown film extrusion." Connect to this title online, 2008. http://etd.lib.clemson.edu/documents/1211388756/.
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Ivings, Krisandra. "Country Culture and Crossover: Narrative Representations of Gender and Genre Through Lyric, Music, Image, and Staging in Carrie Underwood's Blown Away Tour." Thesis, Université d'Ottawa / University of Ottawa, 2016. http://hdl.handle.net/10393/35252.
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This thesis examines the complex and multi-dimensional narratives presented in the work of mainstream female country artist Carrie Underwood, and how her blending of musical genres (pop, rock, and country) affects the narratives pertaining to gender and sexuality that are told through her musical texts. I interrogate the relationships between and among the domains of music, lyrics, images, and staging in Underwood’s live performances (Blown Away Tour: Live DVD) and related music videos in order to identify how these gendered narratives relate to genre, and more specifically,
where these performances and videos adhere to, expand on, or break from country music tropes and traditions. Adopting an interlocking theoretical approach grounded in genre theory, gender theory, narrative theory in the context of popular music, and happiness theory, I examine how, as a female artist in the country music industry, Underwood uses genre-blending to construct complex gendered narratives in her musical texts. Ultimately, I find that in her Blown Away Tour: Live DVD, Underwood uses diverse narrative strategies, sometimes drawing on country tropes, to engage
techniques and stylistic influences of several pop and rock styles, and in doing so explores the gender norms of those genres.
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Butterfield, Craig. "A novel laboratory dispersive and distributive minimixer and applications : development of a new minimixer that can duplicate mixing which occurs in a large twin screw extruder." Thesis, University of Bradford, 2009. http://hdl.handle.net/10454/4930.
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The mixing of additives into a plastic is an extremely important step in the plastics industry, necessary for the manufacture of almost every conceivable product. Therefore the costs in developing new products can prove very expensive as the testing is usually carried out using full scale machines, usually using twin screw extruders because they are able to provide good dispersive and distributive mixing. This is particularly important when compounding difficult to disperse additives and nano-additives. What is required is a machine that can replicate the mixing abilities of a twin-screw extruder but on a laboratory scale. There have been attempts by industry to develop smaller machines, such as the Thermo Scientific HAAKE Minilab II Micro Compounder which processes on the scale of 7 cm3 of material volume. This can be too small for some needs and therefore a machine is required to produce material on the 10g to 100g scale. To this end a laboratory mixer of novel design was devised and its mixing performance was assessed using conductive carbon black and compared against the Thermo Scientific HAAKE Minilab II Micro Compounder, a 19 mm co-rotating twin-screw extruder and a 40 mm co-rotating twin-screw extruder. Carbon black was used because mixing performance can be assessed by measuring the minimum carbon loading necessary to induce electrical conductivity. It was found that the minimixer was able to induce electrical conductivity at loading of 5.75% but the comparison with the other machines proved difficult as the achievement of the threshold at which semi-conductivity occurred appeared independent of shear rate and mixing duration.
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Arruda, Liliane Cardoso. "Efeitos do extensor de cadeia na morfologia, propriedades reológicas e mecânicas de filme tubular de blendas de poli(ácido) láctico) PLA com poli(butileno-adipato-co-tereftlalato) PBAT." Universidade Federal de Sergipe, 2015. https://ri.ufs.br/handle/riufs/3478.
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This study investigated the effect of chain extender epoxy based additive, Joncryl ADR 4368, on the rheological, thermal and mechanical properties of poly(lactic acid) with poly(butylene adipate-co-terephthalate) (PLA/PBAT) blends in the blown films form. Compositions with 40% and 60% by weight PLA were selected for production of such blown films. These dispersed phase content was chosen because the literature does not present mechanical behavior studies of tubular film blends with high concentration of the dispersed phase. Rheological analysis in dynamic oscillatory regime showed the reaction of epoxy group with end chain in both polymers, and a higher reactivity of the chain extender with PLA. The films produced exhibited different morphologies according to the blend composition and chain extender content. Films containing 40% PLA presented the dispersed phase morphology in a fibrillar form; however in the presence of chain extender, the dispersed phase is presented as ellipsoids. This change in morphology resulted in a reduction in the mechanical properties of these films in tensile tests. Films containing 60% PLA had a coarse morphology with dispersed phase in the ribbons-like form. The addition of extender yielded a refinement of the dispersed phase morphology from ribbon to elongated fibril form, which is responsible for the mechanical properties improvement of these films. Despite the low adhesion between matrix and dispersed phase, the proper setting of the morphology of the blends as a function of additive content, allowed to produce films with mechanical properties quite different from each other.Neste trabalho foi estudado o efeito do aditivo extensor de cadeia à base de epóxi, Joncryl ADR 4368, nas propriedades reológicas, térmicas e mecânicas de filmes tubulares de blendas de poli(ácido láctico) com poli(butileno adipato-co-tereftalato) (PLA/PBAT). Composições com 40% e 60% em peso de PLA foram selecionadas para produção destes filmes tubulares. Estes teores de fase dispersa foram escolhidos pelo fato da literatura não apresentar estudos de comportamento mecânico de filmes tubulares de blendas com alta concentração da fase dispersa. Análises reológicas em regime dinâmico oscilatório evidenciaram a reação do grupo epóxi com finais de cadeia de ambos os polímeros, e evidenciaram uma maior reatividade do extensor com o PLA. Os filmes produzidos apresentaram diferentes morfologias de acordo com a composição da blenda e o teor de extensor de cadeia adicionado. Filmes contendo 40% de PLA apresentaram uma morfologia da fase dispersa na forma fibrilar; já na presença do extensor, a fase dispersa se apresentou na forma de elipsóides. Esta mudança na morfologia acarretou em uma redução nas propriedades mecânicas destes filmes em ensaios de tração. Filmes contendo 60% de PLA apresentaram uma morfologia grosseira com a fase dispersa na forma de fitas. A adição do extensor proporcionou um refinamento na morfologia da fase dispersa com formação de fibrilas alongadas, responsável pelo ganho nas propriedades mecânicas destes filmes. Apesar da baixa adesão entre matriz e fase dispersa, o ajuste apropriado da morfologia das blendas, em função do teor de aditivo, possibilitou produzir filmes com propriedades mecânicas bastante diferenciadas entre si.
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Tang, Zuojian 1967. "Surface morphology of polyethylene blown films." Thesis, McGill University, 2000. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=31072.
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The properties of blown polyethylene (PE) films depend on various factors, including crystallinity, morphology, and orientation, in addition to chemical composition. It has been shown that the optical properties are strongly influenced by surface morphology. In this project, we use non-contact atomic force microscopy (AFM) and polarized light microscopy (PLM) to visualize surface and bulk morphology. Various techniques, such as surface and line roughness, surface and line fractal dimension, pair-correlation function and nearest neighbor distance distribution function, are employed to quantify the description of morphology and to compare the morphological characteristics of a number of polyolefin films of commercial interest. A comprehensive quantitative analysis of surface topography has been performed. The co-monomer of the PE resins was found to play a significant role in the formation and the orientation of spherulite-like domains. The film cross-section microstructure has been evaluated qualitatively by using both AFM and PLM. However, quantitative analysis of bulk morphology cannot be obtained due to knife effects.
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Wang, Lei 1972. "Morphology and optical properties of polyolefin blown films." Thesis, McGill University, 1999. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=36728.
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Optical properties of polyethylene blown films are of great commercial and scientific interest. An understanding of the relationship between morphology and optical properties will have a significant impact on product and process optimization.In this work, a number of linear low density polyethylene (LLDPE) resins of different molecular and structural characteristics were studied. Intrinsic properties such as refractive index and absorption coefficient were estimated from resin compositions using group contribution models. The refractive indices of sample films were also measured using the method of Transmission Spectrum.
The morphology of polyethylene films was investigated using Atomic Force Microscopy (AFM) and Near-field Scanning Optical Microscopy (NSOM). Both the surface and bulk morphologies were evaluated. The observation shows the dominant spherulitic structure on the surface as well as in the bulk, as the result of nucleation and crystallization during the film blowing process. In addition to qualitative observations and comparisons; quantitative characterization methods were employed to describe the features of the morphology.
Based on the morphology characterization, the surface reflection was described by the Beckmann-Davies theory of reflection of electro-magnetic waves by rough surface. The directional distribution of reflected intensity was computed according to the surface roughness information. The gloss values of sample films were computed accordingly and compared with experimental measurements. Furthermore, the problem of light transmission and scattering was investigated. A scattering geometry was proposed from the observations of the morphology of sample films. The light scattering by the surface of polymer films was analyzed using a model that is based on the Mie theory of scattering. The haze values of sample films were computed and compared with experimental measurements.
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Wang, Lei. "Morphology and optical properties of polyolefin blown films." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape3/PQDD_0029/NQ64689.pdf.
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BAFNA, AYUSH ASHOK. "OPTICAL PROPERTIES AND ORIENTATION IN POLYETHYLENE BLOWN FILMS." University of Cincinnati / OhioLINK, 2001. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1005857011.
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Walha, Fatma. "Elaboration de mélanges à base de Bio-polymères : Etude des corrélations entre structure, propriétés et transformation." Thesis, Lyon, 2017. http://www.theses.fr/2017LYSEI075.
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Cette étude est une contribution à la mise au point d’un nouveau matériau filmogène multiphasique, originaire de ressources naturelles et destiné à l’emballage alimentaire. La voie proposée consiste à élaborer un mélange poly (acide lactique) [PLA]/ polyamide 11 [PA11] à différentes compositions; le principal avantage étant d’offrir un éventail de propriétés difficile à réunir sur un même polymère. Les différentes formulations, PLA/PA11, élaborées à l’état fondu dans une extrudeuse bivis ont été étudiés du point de vue des propriétés rhéologiques, thermique, mécanique et de la morphologie. Différents tiers-corps copolymères de structures diverses ont été utilisés, à différents taux, dans le but de promouvoir l’adhésion à l’interface des composants et améliorer les performances des mélanges ainsi conçus. La finalité est d’appréhender une formulation qui soit filmogène, tout en ayant un comportement en élongation, à l’état fondu, parfaitement compatible avec les conditions de transformation par extrusion gonflage de gaineThis study is a contribution to the development of a new biomaterial with suitable melt strength, stiffness-to-toughness balance, and the required thermal performance for food packaging applications. The proposed approach consists in preparing a mixture of poly (lactic acid) [PLA] / polyamide 11 [PA11] with different compositions; the main advantage being to offer a range of properties that are difficult to combine on the same polymer. The different formulations, PLA/PA11, processed in the molten state in a twin-screw extruder were studied from the side of rheological, thermal, mechanical and morphology. Different copolymers of various structures were used, at different rates, in order to promote the adhesion in the interface of the components and to improve the blend systems performances. The aim is to obtain a formulation that having an elongation behavior, in the molten state, perfectly compatible with the blowing process
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Belyamani, Imane. "Développement d'un matériau thermoplastique biodégradable et hydrosoluble à base d'une protéine du lait." Phd thesis, Université Jean Monnet - Saint-Etienne, 2011. http://tel.archives-ouvertes.fr/tel-00702749.
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La biomasse représente l'une des principales alternatives à l'utilisation du pétrole dans la plasturgie. Grâce à leurs propriétés fonctionnelles, les caséinates sont une matière première prometteuse pour la fabrication de films plastiques pour des applications dans l'emballage biodégradable et hydrosoluble. La transformation du caséinate de sodium par les techniques habituellement utilisées dans la plasturgie a été démontrée. Des extrudats de caséinate plastifié au glycérol ont été obtenus au moyen d'une extrudeuse bi-vis corotative. La caractérisation physico-chimique du matériau obtenu a confirmé la thermostabilité de cette protéine et a montré la dépendance du comportement du matériau vis-à-vis de l'humidité ambiante. Pour une variation du taux d'Humidité Relative, de 40 à 90% et une augmentation de la concentration du glycérol, plastifiant hygroscopique, le matériau passe d'un état vitreux (rigide) à un état caoutchouteux (mou). Des films fins ont été ensuite réalisés, à partir des extrudats thermoplastiques, par extrusion gonflage. La perméabilité à la vapeur d'eau des films de caséinate de sodium a été étudiée et a montré que ces matériaux sont de mauvaises barrières à l'humidité. La deuxième partie a été consacré à l'étude de mélanges caséinate de sodium/caséinate de calcium d'un côté et caséinate de sodium/PBAT de l'autre. Le mélange des deux caséinates a permis d'augmenter la tenue mécanique du mélange, à partir de 50% de caséinate de calcium, et de retarder le transfert hydrique à travers le film. Dans le même sens, l'ajout du PBAT, a augmenté jusqu'à deux fois plus, le module d'Young des mélanges mais a baissé la résistance au transfert d'humidité du film à cause de l'incompatibilité des deux polymères.
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Žukauskas, Petras. "„Koncept-dizaino” plano parengimas įdiegiant „Blow-Fill-Seal” aseptinę technologiją akių lašams gaminti." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2014. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2014~D_20140630_134849-50340.
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Darbo tikslas: Išsiaiškinti „Blow-Fill-Seal” technologijos pritaikymo galimybes gaminant akių lašus, sukurti koncepcinį planą įtraukiant patalpų išplanavimą ir galimą sąmatą. Darbo uždaviniai: 1. Pateikti gamybinės linijos proceso pasiūlymą pritaikant technologiją; 2. Sudaryti patalpų planą pritaikant akių lašų gamybą, nurodyti medžiagų ir personalo judėjimą patalpose; 3. Pateikti siūlymus įrengiant švarias patalpas (architektūriniai, vandens tiekimo ir kt. sprendimai); 4. Pateikti technologinių įrengimų pasiūlymus, injekcinio vandens tiekimą; 5. Pateikti galimą projekto sąmatą. Tyrimo metodai apima aktualią literatūros apžvalgą, rekomendacijų, įvairių praktikų, nuostatų bei reglamentų analizę koncentruojantis ties akių lašų gamyba, aseptinių procesų ir su jais susijusių kitų sistemų ar procesų įrengimu, paruošimu bei valdymu, teorinio projektavimo pagrindais. Rezultatuose išskiriamas akivaizdus technologijos praktinio pritaikymo efektyvumas gaminant akių lašus aseptinėmis sąlygomis. Juose patvirtinama ir koncepcinio plano svarba, esmė - tai privalomas elementas, kuris nuo pat pradžių privalo būti teisingas. Išvadose išskiriamas technologijos našumas ir efektyvumas. Taip pat pažymimi planai, jų atlikimo svarba įrengiant patalpas. Naudojamos medžiagos įrengiant švarias patalpas turi būti aukščiausios kokybės, nesukelti papildomų rūpesčių užtikrinant švarą jose. Pasiūlyti įsigyti įrengimai. Projekto sąmata siekia 19,082,000Lt.Scope: real time use of „Blow-Fill-Seal“ technology in producing ophthalmological preparations, create concept plan including detail room planning and estimated cost layout. Tasks: 1. Suggest a production line using this technology; 2. Create area plan with all rooms designed for making eye drops production, point raw materials and personnel movement; 3. Suggest materials used in creating clean rooms (architectural, water supply etc. solutions); 4. Suggest needed technological apparatus, water for injection supply; 5. Calculate possible estimate. Research methods include review on topical literature, recommendations, practices, statutes and regulations analysis based on liquid ophthalmological preparations‘ processing, aseptic processes‘ and related systems or other processes‘ installation, preparation and controlling, basic and theoretical projection. This technology has obvious practical effectiveness when using it for aseptic eye drops production. Also, the importance and essence of concept design is shown – it is a obligatory element, which has to be correct from the very beginning. Work concludes main technological productivity and effectiveness, notices of area planning importance when creating concept plan. All materials used in clean rooms should be high-end products ensuring safe and clean working space. Technological and other apparatus proposal. Project would approximately estimate 19,082,000Lt.
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Breese, David R. "Modeling the effects of solid state orientation on blown high molecular weight high density polyethylene films a composite theory approach /." Cincinnati, Ohio : University of Cincinnati, 2004. http://www.ohiolink.edu/etd/view.cgi?acc%5Fnum=ucin1107958634.
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BREESE, DAVID RYAN. "MODELING THE EFFECTS OF SOLID STATE ORIENTATION ON BLOWN HIGH MOLECULAR WEIGHT HIGH DENSITY POLYETHYLENE FILMS: A COMPOSITE THEORY APPROACH." University of Cincinnati / OhioLINK, 2005. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1107958634.
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Tobe, Renée. "Mimesis and the dialogue between architecture and film, with particular reference to Joseph Losey's 'The Servant' and Michelangelo Antonioni's 'Blow-up'." Thesis, University of Cambridge, 2003. https://www.repository.cam.ac.uk/handle/1810/284026.
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Bermingham, Siobhan Clara. "The effect of processing parameters on the properties of blown films produced from blends of a low density and a butene based linear low density polyethylene." Thesis, Queen's University Belfast, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.282120.
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Ben, Larbi Sami. "TALK TO ME, I AM LISTENING." VCU Scholars Compass, 2009. http://scholarscompass.vcu.edu/etd/2007.
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An introductory conversation with a new person I just met usually goes like this: So, where is your accent from ? Are you American? Well, yes, .....but no. Not really. I do have American citizenship and I lived in the US for fifteen years but I grew up in France. Ok, so you’re French? Well, yes, but .....not totally. My mother is French but my father is Tunisian. Ok, so you’re Tunisian? Well, yes, but... not wholly. I don’t speak Arabic, so I don’t totally feel Tunisian. So what are you? American? French? Tunisian? With my work, I ask the same questions. What is this? What does it do? How do I, the maker, relate to it? How does the viewer, the other side of the conversation, relate to it and understand it? Can we understand each other if we do not speak the same language? Who am I and who are you anyway?
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Luo, Dah-Woei, and 羅大偉. "Computer aided design of extrusion blown film die." Thesis, 1997. http://ndltd.ncl.edu.tw/handle/23832717614982963083.
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碩士國立交通大學
應用化學研究所
85
The blown film die , which is also called the spiral mandrel die , is widely used in the production of tubular products , such as pipes , plastic bags and so on . In order to produce the beautiful and durable products , helicalgrooves cut on the mandrel surface are designed to increase flow uniformity and eliminate welding lines . They are the main characteristics of the spiral mandrel die . There are six parameters in designing the spiral mandrel die , which are the diameter of the mandrel , the number of the helical groove , the initial width of the helical groove , the initial depth of the helical groove , the helical angle and the gap , respectively . This study analyzed the isothermal-non-Newtonian flow , based on the two-dimensional flow simulation , in a die with a mandrel of 11 cm diameter and four helical grooves . Then , the Taguchi method was used to determine the optimal values of the rest of four parameters by considering the performance of the die . The performance of the die was examined from flow uniformity , degree of mixing and total pressure drop . Finally , the optimal geometry of the die was determined . Sequentially , the performance of the die was examined under the nonisothermal condition and the discrepancy between the isothermal and the nonisothermal condition was compared . The results show that it is enough to determine the elementary shape of the die according to the isothermal assumption .
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WANG，CHIA-CHAN and 王家榐. "Development of Toughening and Blown Film of Polylactic Acid." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/7cw457.
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碩士亞東技術學院
材料與纖維系應用科技碩士班
107
This study is divided into two parts to discuss, the first part: polylactic acid (PLA) toughening and upgrading. First, PBAT, PBS and PLA biodegradable plastics were mixed in different proportions to prepare PmCn and PLA1(PmCn)1 composite plastics. The thermal, mechanical, SEM type, film formation and heat resistance of the film were analyzed and discussed. The thermal properties show that the melting exothermic peak belonging to P disappeared in P1C4 plastic, P was dispersed in the main phase of C, and the other mixing ratios were found to be the melting exothermic peaks of P and C. It was also found in the PLA1(P1C4)1 plastic that the melting exothermic peak belonging to P completely disappeared. P1C4 is blended into an alloy-like composite plastic. When blended with PLA, the P1C4 alloy is dispersed in the PLA main phase. The mechanical properties show that P1C4 plastic has the highest tensile strength. Compared with 100% C, the strength decreases by 20.9% and the elongation increases by 39.8%. PLA1(PmCn)1 plastic with PLA1(P1C4)1 plastic has the highest tensile strength and elongation at break. Compared with PLA, the tensile strength decreased by 52.6% and the elongation increased by 9465%. The increased elongation is of great help in blown film processing. The mechanical properties of the film showed that the PLA1(P1C1)1 plastic had an average tensile strength (X-axis: 17.3 MPa; Y-axis: 17.3 MPa) and elongation at break (X-axis: 45.9%; Y-axis: 218%). The heat resistance stability of the film shows that the PmCn and PLA1(PmCn)1 plastics are tested at 95 ° C, and the deformation amount falls between 0 and 3 mm, and the heat resistance is good. The type properties show that the P1C4 and PLA1(P1C4)1 plastics have a smooth and flat surface. In summary, PmCn and PLA1(PmCn)1 plastics are partially compatible composite plastics. P1C4 is alloyed with PLA. Compatible formulations P1C4 and PLA1(P1C4)1 plastics have the best physical properties, and blown film forming has excellent results. Part II: The first part of the successful development of PLA1(P1C4)1 plastic, mixed with oyster shell powder, fatty acid guanamine dispersant in different proportions, prepared TPLAxOy and TPLAxOyDz composite plastic. The thermal, mechanical, SEM type, film forming properties and heat resistance properties of the composite plastics were analyzed and discussed. The thermal properties show that the TPLAxOy plastic part has a large increase in crystallinity with the increase of oyster shell powder content. In TPLA85O15 plastic, the crystallinity is 80.2%, and the crystallinity is increased by 20.6 wt% compared with TPLA. The mechanical properties show that the TPLAxOy plastic part, with the addition of oyster shell powder, the Young's coefficient value increased significantly, with TPLAO1 plastic 464MPa highest. In the plastic part of TPLAxOyDz, with the increase of the content of oyster shell powder, the value of Young's coefficient increased greatly, with TPLA of TPLAO5D3 plastic being the highest. Compared with TPLA plastic, the Young's coefficient was increased to 884%. The addition of oyster shell powder and dispersant destroys the toughening properties of TPLA, and the stiffness of the plastic increases. The heat resistant properties of the film show that the TPLA95O5D3 film can be heat resistant to 100 ° C when the film thickness is ≧ 0.05 mm. The type properties showed that most of the oyster shell powder was broken up in the TPLA95O5 test piece, and the size was less than 1 μm, which was uniformly dispersed in the continuous phase TPLA plastic. In summary, the oyster shell powder is added to the TPLA plastic to increase the crystallinity of the PBS, and the oyster shell powder is a nucleating agent for PBS. Adding a dispersant to the TPLA plastic increases the stiffness of the plastic. Further, in the blown film forming process, when the oyster shell powder is added in an amount of 10%, the blown film forming process has an excellent effect. Keywords: Polylactic acid、Oyster shell powder、Toughening、Film
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Tao, Wen-Yu, and 陶文鈺. "Optimal Design of Spiral Mandrel Die for Blown Film Process." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/28458438614523602582.
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碩士國立交通大學
應用化學系
90
Spiral mandrel dies are widely used in the production of tubular products and polymeric films. The feature of the die is several helical grooves cut on the mandrel surface, and the melt flow from groove leak to clearance gradually. Proper die design can improve flow uniformity and to avoid occurring the weld line. Geometrical parameters in designing the spiral mandrel die are: diameter of the mandrel, the number of helical groove, initial width and initial depth of the helical groove, the groove helix angle, overlap of helical groove, the initial gap, and the taper angle, which we introduce two-sectional design. In this article we analyze non-Newtonian fluid flow in the die. Two-dimension mathematical model is utilized, and the viscosity of polymer melt is assumed to be Power-Law model. Associated with Taguchi method, several optimal sets of die geometric parameters is searched by assessing the flow uniformity and mixing degree respectively. We consider more geometric parameters and different targets during searching process to attain both good flow uniformity and mixing degree. Finally, performance of dies under nonisothermal condition is compared with those determined on isothermal condition. Die lips is discussed at the same time.
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Xie, Wei-Xian, and 謝維賢. "Optimal Design of Spiral Die for Metallocene Polyethylene Blown Film." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/18798002837631228667.
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碩士國立交通大學
應用化學系
89
Metallocence polyethylene(m-PE) is a fully potential material with well mechanical properties. But the poor melt strength and high shear rate viscosity are disadvantages in polymer application. Mathematic model combined with Taguchi method is a method for optimal design of spiral mandrel die to avoid the poor melt strength and the overheat of melt. There are seven parameters in designing the spiral mandrel die, which are the diameter of the mandrel, the number of the helical groove, the initial width of the helical groove, the initial depth of the helical groove, the helical angle, the taper angle, and the gap. With m-PE as a processing material, two-dimensional flow simulation and Taguchi method are combined to determine the optimal geometry value, and the performance of the die was discussed. In addition, the performance of the die was examined with die lips. Finally, the performance of the die was examined under nonisothermal condition and compared with under isothermal condition.
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Chang, xein-min, and 張憲民. "Optimal Design of Spiral die for Physical Foaming and blown film extrusion Process." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/94313729520286970079.
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碩士國立交通大學
應用化學系所
92
The purpose of the present study is to establish an analytical program for spiral die with physical foaming agent. First, we predict the viscosity of melt polymer with foaming agent mathematically, and establish the flow model by fluid dynamics. Applying the Sanchez-Lacombe equation, we can calculate the weight percentage of foaming agent in melt polymer at any pressure and temperature. As predicted, more foaming agent can be dissolved into melt polymer at a high pressure or low temperature. The parameters of spiral die include DEPTH, WCHAN, GIBC, HBC, NOSEC, θ and α. Second, we use the Tguchi method to search several optimal sets of die geometric parameters by assessing the flow uniformity(UNI) and mixing degree(MD) isothermally and create ANOVA tables. From ANOVA tables, we realize that the seven parameters can totally describe the flow situation in spiral die. At the same time, we find that whatever the number of channels is, the most relevant parameters with respect to MD are DEPTH,WCHAN and GIBC; with respect to UNI, WCHAN and NOSEC are the most relevant parameters; furthermore, with respect to pressure gradient, GIBC及ALFAR are the most relevant. During polymer foaming, if the local die pressure cannot reach the critical pressure, prefoaming occurs. Therefore, at the outlet of spiral die, we narrow down the channel depth to increase the local pressure, which is thus greater than critical pressure. Finally, with die lip being attached to spiral die, we examine the non-isothermal condition, so that an analytical program for spiral die with physical foaming agent can be established.
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蔡文淵. "Optimal Design of Side-Feed Spiral Mandrel Die for Blown Film Extrusion Process." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/39812762482349170024.
Full textAbstract:
碩士國立交通大學
應用化學系所
93
Abstract Side-feed spiral mandrel die was designed to overcome the disadvantage of central-feed spiral mandrel die. The production rate can be improved and the possibility of forming the poor surface appearance and the warp problem can also be avoided using this type of die. Especially, the possibility of material degradation, which causes the decrease of mechanical properties, can be eliminated via this type of die when the layers of film increase. In addition, this type of die possesses the characteristics of small metal body, which results in a decrease of die cost, and easily taking apart of the die or changing the processing material. Recently, this type of die, thus, has attracted the attention of the foreign equipment suppliers. Therefore, this thesis first employees a flow model of two dimensional control volume method to simulate the flow behavior in the side-feed and spiral mandrel sections. Under this circumstances, the non-Newtonian fluid is assumed to be in the isothermal condition and the flow behavior in these sections will be simulated. In addition, we use the Taguchi method to search several optimal sets of die geometric parameters by assessing the flow uniformity and mixing degree. Finally, under non-isothermal condition, the geometry of die will be extended. This will allow us to simulate the flow behavior and performance of entire die.
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吳祐任. "Optimal disign of side-feed spiral mandrel die for the blown film extrussion process." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/09197149086822723722.
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Ohlendorf, Friedrich [Verfasser]. "Vorhersage der mechanischen Folieneigenschaften bei der Schlauchfolienextrusion = Predicting the mechanical film properties in blown film extrusion / vorgelegt von Friedrich Ohlendorf." 2004. http://d-nb.info/971334374/34.
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Lin, Chin-Tai, and 林錦泰. "The Study of The Effect of The Surface Roughness on Physical Properties for a Blown Film Product." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/15531267795812399958.
Full textAbstract:
碩士國立中正大學
化學工程研究所
93
The extrusion blown film process is widely used and well developed technology in making thin-film products for industrial and packaging applications. Compared to the flat-die process, thicker, wider HDPE geomembrane products manufactured by the blown film (Round-Die) process a lower investment and flexible production issues. The HDPE resins used for the geomembrane production in a blown film process should have a higher molecular weight to provide the required melt strength, and bubble stability . A narrow molecular weight distribution (MWD) is needed for providing requirements of uniform properties of geomembrane products, but the sharkskin (melt-fracture) phenomenon often appears on the surface of the products. This poor appearance will lead to the poor tensile strength and elongation. In this paper some carbon black masterbatches are tested to modify the rheology of HDPE resin. Each carbon black masterbatch is mixed with the HDPE resin, fed into the extruder for testing. The data of melt temperature, melt pressure, torque of the extruder, output, bubble stability, die deposit and surface phenomenon are collected for evaluation. The effects of surface roughness on properties are also studies.
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Xu, Zhen-Peng, and 許振鵬. "Flow simulation in blow-film die." Thesis, 1990. http://ndltd.ncl.edu.tw/handle/08912594264559212384.
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YUAN, CHIANG TING, and 姜丁元. "Investigation of the oxygen barrier properties of blown films of modified polyamide/nylon clay and modified polyamide/ethylene vinyl alcohol blends." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/04595395444276827623.
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Metz, Daniel Curran. "Prestige and prurience : the decline of the American art house and the emergence of sexploitation, 1957-1972." Thesis, 2010. http://hdl.handle.net/2152/ETD-UT-2010-05-1383.
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“Prestige and Prurience: The Decline of the American Art House and the Emergence of Sexploitation, 1957-1972” presents a historical narrative of the art house theatre during the 1960s and its surrounding years, examining the ways in which art theatres transformed into adult theatres during the 1960s and 1970s. Beginning in earnest in the immediate post-war period, art houses in America experienced a short period of growth before stagnating in the middle 1950s. With the release in 1957 of the erotically charged Brigitte Bardot film …And God Created Woman, a new era of art houses followed, one that is characterized by the emergence of sexualized advertising, content and stars. As the 1960s came, sex films like The Immoral Mr. Teas played on art film marketing strategies and even screened in many art houses. Gradually, sexploitation films began to dominate art house programs and replace European art films and Hollywood revivals. In this transitional period, however, sexploitation films used key strategies to emulate many art film characteristics, and likewise art films used sexploitation techniques in order to maintain marketability for American distribution and exhibition. By studying the promotion and programming used by art house theatres during this period, this thesis identifies and announces a number of key trends within the dynamic period for art houses. The period is distinguished by its convergence of practices related to prestigious and prurient signs, merging art and sex in ways unique to the era and to the circumstances by which sex films infiltrated art houses and art films pandered to salacious interests. It presents a new perspective on the history of art houses, art cinema, American exhibition, sexploitation films, hardcore pornography and censorship.text