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Статті в журналах з теми "NANOFILLER MATERIAL"
1
Budiyantoro, Cahyo. "The Influence of Nano Filler on Thermal and Mechanical Properties of Polypropylene." Materials Science Forum 929 (August 2018): 78–85. http://dx.doi.org/10.4028/www.scientific.net/msf.929.78.
Повний текст джерелаАнотація:
In order to obtain specific properties in the commercial and engineering applications, PP materials are often combined with additives. Filler is one of solid additive type that made of inorganic materials and is generally distinguished by its influence on the mechanical properties of the resulting mixture with the plastic matrix. Filler dimension less than 100 nm is often categorized as a nanofiller and added to plastics with the range of percentage from 1% up to 10%. Various studies have been conducted to know the influence of filler on mechanical properties, but this study is also conducted to investigate the effect of nanofillers on thermal properties of PP material. Thermal properties are very important to know from the stage of design, processing until the end use final product. Most plastic products are made in soft or liquid condition, the melting temperature (melting temperature, Tm) becomes the basis of the processing parameter adjustment. Investigations done by comparing the thermal properties of commercial copolymer PP material (virgin material and injection molding specimen) and PP materials containing nanofiller (virgin material and injection molding specimen) by using Differential Scanning Calorimetry (DSC), while data of mechanical properties was obtained by the tensile test. Both 1st heating and 2nd heating DSC Experiment showed that nanofilled PP need the highest endothermic effect (2.63 W/g and 1.79 W/g), but nanofiller gave no effect on melting temperature to all type of specimens (in the range of 164.3 – 166.3 °C). The elastic modulus of nanofilled PP was around 1486 Mpa, higher than non-filled PP (999 Mpa).
2
Ibrahim, Mohamed E., M. Osama Abed el-Raouf, and Nourhan A. Mohamed. "Towards a Generalized Electric Breakdown Mechanism of Insulating Nanofluids." Nano Hybrids and Composites 36 (June 20, 2022): 81–88. http://dx.doi.org/10.4028/p-jj4qou.
Повний текст джерелаАнотація:
Recently, addition of nanofillers to insulating fluids to increase its breakdown voltage finds a great interest from researchers. Understanding the reasons of the increased breakdown voltage with addition of nanofillers at certain loadings to insulating fluids is of great importance. Hence, understanding how electric breakdown occurs in nanofluids can help researchers to select the more suitable nanofiller material, nanofiller particle size ....... etc. to be added to insulating fluids. Therefore, in this paper, a generalized electric breakdown mechanism of insulating nanofluids is presented. The generalized mechanism takes different parameters into consideration. These parameters are nanoparticle permittivity, nanoparticle size and insulating fluid temperature. To demonstrate the validity of the generalized breakdown mechanism, theoretical computations are carried out using finite element analysis. Also, breakdown experiments considering transformer oil are carried out considering different nanofiller materials, nanofiller sizes at different temperatures.
3
Fang, Xin, Jinjin Rong, Yilin Deng, and Moon-Hwan Jee. "Research on Processing Technology Product Design and the Application of Nano-Wood-Plastic Composite Materials." Journal of Nanoscience and Nanotechnology 20, no. 12 (December 1, 2020): 7787–92. http://dx.doi.org/10.1166/jnn.2020.18881.
Повний текст джерелаАнотація:
This study focused on the design of wood-plastic composite (WPC) products. In this study, recycled high-density polyethylene plastic was used as the matrix, wood powder was used as the filler, different types of nanofillers and self-synthesized nanofiller treatment agents were added, and the twin-screw extrusion granulation method was used to prepare nano-WPC materials. The effects of different types of nanofillers on the mechanical properties of nano-WPC materials were investigated, and the cross-sectional structures of the materials were analyzed by scanning electron microscopy. The results showed that nanofiller treatment agents improved the interface compatibility of the materials. When the treatment agent content reached 2.5% and the nano-montmorillonite content reached 10%, the mechanical properties of the material reach their maximum values.
4
Krishnan, Arun, and L. Roy Xu. "A Simple Effective Flaw Model on Analyzing the Nanofiller Agglomeration Effect of Nanocomposite Materials." Journal of Nanomaterials 2012 (2012): 1–5. http://dx.doi.org/10.1155/2012/483093.
Повний текст джерелаАнотація:
A special mechanics/material phenomenon involving nanocomposites is the agglomeration of nanofillers at high volume fractions of nanofillers. Numerous experimental investigations on nanocomposites have indicated a significant decrease in mechanical properties, due to the agglomeration of nanofillers. This paper describes a simple effective flaw model to correlate the local mechanical behavior of agglomerated nanoparticles with the change in global strengths of nanocomposites. The estimated bending strength reduction from our model is shown to be similar to experimental results reported by previous researchers. These results can be used as a guide for future nanocomposite design and development. Future nanomaterial manufacturing should be focused on eliminating the largest agglomerates, rather than limiting the nanofiller volume fraction. Meanwhile, by reducing the nanofiller agglomerate size, we expect that a high critical nanofiller volume fraction could be obtained to delay the mechanical property reduction.
5
Ibrahim, Mohamed E., Elsayed Tag Eldin, Safaa F. Elzoghby, Mohamed A. Izzularab, and Amr M. Abd-Elhady. "The Role of the Accumulated Surface Charge on Nanoparticles in Improving the Breakdown Strength of Liquid and Solid Insulation." Energies 15, no. 13 (July 2, 2022): 4860. http://dx.doi.org/10.3390/en15134860.
Повний текст джерелаАнотація:
In this paper, the role of the accumulated surface charge on the surfaces of nanoparticles on breakdown strength for liquid and solid dielectrics is presented. The breakdown strengths of a nanofilled liquid dielectric and a solid dielectric are evaluated. The evaluation was conducted considering different nanoparticle material types with different nanofiller loadings. Accordingly, the preparation of transformer oil nanofluid and silicone rubber nanocomposites was performed with different nanofillers of the same average particle size. Breakdown voltage was measured for all the prepared samples, both liquid and solid. The interpretation of the obtained results is presented.
6
Nawawi, Zainuddin, R. F. Kurnia, N. F. A. Isa, Z. Buntat, D. R. Yuniarti, M. I. Jambak, and Muhammad Abu Bakar Sidik. "Electrical Potential Distribution in Polymethyl Methacrylate-Graphene Oxide Nanocomposites." Indonesian Journal of Electrical Engineering and Computer Science 4, no. 2 (November 1, 2016): 256. http://dx.doi.org/10.11591/ijeecs.v4.i2.pp256-262.
Повний текст джерелаАнотація:
<p>Research work of polymer nanocomposites in high voltage insulator becomes interest nowadays. Polymer based and nanofillers are the core components in polymer nanocomposites. By adding such a big amount of nanofiller it would enhance the electrical and mechanical properties of polymers. However as for today, a little percentage of nanofiller concentration could dramatically enhanced the properties of the polymeric material. Recent research of graphene oxide (GO) nanofiller has brought to this project interest. This paper presents several methods that have been published to development PMMA (poly methyl methacrylate)/GO nanocomposites and a simulation of PMMA/GO in order to investigate the potential distribution. </p>
7
Abdul Razak, Nurul Iman, Noor Izyan Syazana Mohd Yusoff, Mohd Hafizi Ahmad, Muzafar Zulkifli, and Mat Uzir Wahit. "Dielectric, Mechanical, and Thermal Properties of Crosslinked Polyethylene Nanocomposite with Hybrid Nanofillers." Polymers 15, no. 7 (March 29, 2023): 1702. http://dx.doi.org/10.3390/polym15071702.
Повний текст джерелаАнотація:
Crosslinked polyethylene (XLPE) nanocomposite has superior insulation performance due to its excellent dielectric, mechanical, and thermal properties. The incorporation of nano-sized fillers drastically improved these properties in XLPE matrix due to the reinforcing effect of interfacial region between the XLPE–nanofillers. Good interfacial strength can be further improved by introducing a hybrid system nanofiller as a result of synergistic interaction between the nanofiller relative to a single filler system. Another factor affecting interfacial strength is the amount of hybrid nanofiller. Therefore, the incorporation amount of hybridising layered double hydroxide (LDH) with aluminium oxide (Al2O3) nanofiller into the XLPE matrix was investigated. Herein, the influence of hybrid nanofiller content and the 1:1 ratio of LDH to Al2O3 on the dielectric, mechanical, and thermal properties of the nanocomposite was studied. The structure and morphology of the XLPE/LDH-Al2O3 nanocomposites revealed that the hybridisation of nanofiller improved the dispersion state. The dielectric, mechanical, and thermal properties, including partial discharge resistance, AC breakdown strength, and tensile properties (tensile strength, Young’s modulus, and elongation at break) were enhanced since it was influenced by the synergetic effect of the LDH-Al2O3 nanofiller. These properties were increased at optimal value of 0.8 wt.% before decreasing with increasing hybrid nanofiller. It was found that the value of PD magnitude improvement went down to 47.8% and AC breakdown strength increased by 15.6% as compared to pure XLPE. The mechanical properties were enhanced by 14.4%, 31.7%, and 23% for tensile strength, Young’s modulus, and elongation at break, respectively. Of note, the hybridisation of nanofillers opens a new perspective in developing insulating material based on XLPE nanocomposite.
8
Sundarakannan, R., K. Balamurugan, Y. Jyothi, V. Arumugaprabu, Thanikodi Sathish, Z. Mahmoud, El Sayed Yousef, Dadapeer Basheer, and Saboor Shaik. "Importance of Fiber-/Nanofiller-Based Polymer Composites in Mechanical and Erosion Performance: A Review." Journal of Nanomaterials 2023 (February 8, 2023): 1–16. http://dx.doi.org/10.1155/2023/3528977.
Повний текст джерелаАнотація:
The addition of nanofillers in the polymer matrix composites (PMC) has shown a considerable improvement in the mechanical properties and acts as a suitable replacement material. Among the various properties, erosion studies play a key role in the establishment of new materials in engineering applications irrespective of material properties. This paper primarily focus on mechanical properties of PMC and provides a view of the erosion studies conducted on various PMC that are reinforced with natural fibers and nanofillers. The study related to natural fiber as secondary reinforcement and nanofiller as primary reinforcement is taken into consideration. The natural fibers such as sisal-, pineapple-, jute-, bamboo-, banana-based polymer composites and their improvement in mechanical properties by the addition of various fillers are compared and reported. From the survey, it was noticed that the incorporation of nanofillers with natural fiber and polymers provides an acceptable range of material behavior. Being the natural fiber and its proper surface treatment enhance erosion resistance behavior.
9
Tonprasong, Watcharapong, Masanao Inokoshi, Muneaki Tamura, Motohiro Uo, Takahiro Wada, Rena Takahashi, Keita Hatano, Makoto Shimizubata, and Shunsuke Minakuchi. "Tissue Conditioner Incorporating a Nano-Sized Surface Pre-Reacted Glass-Ionomer (S-PRG) Filler." Materials 14, no. 21 (November 4, 2021): 6648. http://dx.doi.org/10.3390/ma14216648.
Повний текст джерелаАнотація:
We aimed to evaluate the properties of a novel tissue conditioner containing a surface pre-reacted glass-ionomer (S-PRG) nanofiller. Tissue conditioners containing 0 (control), 2.5, 5, 10, 20, or 30 wt% S-PRG nanofiller or 10 or 20 wt% S-PRG microfiller were prepared. The S-PRG nanofillers and microfillers were observed using scanning electron microscopy. The ion release, acid buffering capacity, detail reproduction, consistency, Shore A0 hardness, surface roughness, and Candida albicans adhesion of the tissue conditioners were examined. The results indicated that the nanofiller particles were smaller and more homogeneous in size than the microfiller particles. In addition, Al, B, F, and Sr ions eluted from S-PRG were generally found to decrease after 1 day. Acid neutralization was confirmed in a concentration-dependent manner. The mechanical properties of tissue conditioners containing S-PRG nanofiller were clinically acceptable according to ISO standard 10139-1:2018, although the surface roughness increased with increasing filler content. Conditioners with 5–30 wt% nanofiller had a sublethal effect on C. albicans and reduced fungal adhesion in vitro. In summary, tissue conditioner containing at least 5 wt% S-PRG nanofiller can reduce C. albicans adhesion and has potential as an alternative soft lining material.
10
Lanna, Aunnuda, Montri Suklueng, Chainuson Kasagepongsan, and Sunisa Suchat. "Performance of Novel Engineered Materials from Epoxy Resin with Modified Epoxidized Natural Rubber and Nanocellulose or Nanosilica." Advances in Polymer Technology 2020 (January 10, 2020): 1–11. http://dx.doi.org/10.1155/2020/2123836.
Повний текст джерелаАнотація:
Performance of new engineered material from epoxy resins with modified epoxidized natural rubber (ENR) and nanofillers were investigated. ENR from renewable natural crop resources is a type of green material with potential to partially substitute or replace and toughen petrochemical-based polymers. Nanocomposites (epoxy resin/ENR/fillers nanoparticles) were characterized with Fourier transform infrared spectroscopy (FTIR), dynamic light scattering (DLS), atomic force microscope (AFM), and scanning electron microscopy (SEM). Comparison of characterized and mechanical properties of nanofiller reinforced with both nanocellulose and nanosilica were studied. The nanocomposites were characterized for their mechanical properties (e.g., impact strength, tensile strength) and thermal degradation behaviour by thermal gravimetric analysis (TGA). Mechanical property investigation results show that, the impact strength of nanocomposites, can be improved by blending in ENR 50 mixed with nanofiller, relative to the baseline nanocomposite mixers. The nanofiller loading in epoxy composite showed the highest improvement in mechanical properties at 0.75 phr (parts per hundred of resin). Effects of accelerated weathering aging were evaluated, and the observed changes were larger with nanosilica than with nanocellulose filler. Here, the accelerated aging increase in tensile properties was found to be 10% after 14 days in both nanofillers, while the other mechanical properties did not change significantly. These nanocomposites are expected to have high wear rates limiting their service life.
Дисертації з теми "NANOFILLER MATERIAL"
1
Adegbotolu, Urenna V. "Demulsification and recycling of spent oil based drilling fluid as nanofiller for polyamide 6 nanocomposites." Thesis, Robert Gordon University, 2016. http://hdl.handle.net/10059/3136.
Повний текст джерелаАнотація:
Spent oil based drilling fluid and cutting wastes are global liabilities due to their hazardous hydrocarbon content which impacts negatively on flora, fauna, and global carbon footprint. The formulation of two demulsifiers to ensure chemically enhanced phase separation of this waste into oil, water and solid components was successfully carried out in addition to recycling the solid phase into PA6 nanocomposite materials. Initial characterisation of the untreated waste was carried out by Fourier Transform Infra Red (FTIR) for total petroleum hydrocarbon (TPH) analysis, Inductively coupled plasma optical emission spectrometry (ICPOES) for quantitative elemental analysis and Energy dispersive xray analysis (EDXA) for qualitative elemental composition amongst other characterisation methods. The analysis showed that the sample had a high hydrocarbon load of 662,500mg/kg and a high heavy metal load for Pb of 122mg/kg. No As, Cd, Hg were detected. The demulsifier formulations were composed of isopropanol, sodium dodecyl sulphate, poloxamer, sodium chloride, chitosan in 0.2M acetic acid and deionised water for demulsifier S4 and addition of phosphoric acid for demulsifier S3. Hydrocarbon reduction on the extracted solid phase nanofiller S3 and nanofiller S4 was 98.6% and 98.5% respectively after demulsification. The demulsified spent oil based drilling fluid solid extracts were below OSPAR regulation of < 1% oil on cutting by weight. However, recycling of the recovered solid was carried out in order to achieve environmentally sustainable management of the waste in Polyamide 6 (PA6) nanocomposite manufacture/fabrication. The formulation of different blends of PA6 nanocomposite materials from untreated, demulsifier treated and thermally treated drilling fluid and cuttings was successfully achieved. Nanocomposite leaching test showed Pb immobilisation. The flexural and compressive - modulus and strength of the PA6 were markedly improved in the presence of the nanofillers and glass fibre. This was attributed to the reinforcement, exfoliating, stiffening, rigidity effect of the nanofillers. S6 (untreated drilling fluid) nanofillers significantly improved the mechanical properties of PA6. This was attributed to the increased interfacial bonding between the fillers and the polymer matrix as a result of the petroleum hydrocarbon present in the sample. The Thermogravemetric analysis (TGA) results showed that nanocomposites PA6/S3 and PA6/S3/GF30 had improved the thermal stability of PA6 by 13.6% and 38.8% respectively compared to PA6/S2 and PA6/S2/GF30 (simulated commercial nanocomposite materials) that improved PA6 by 9.7% and 35.8% respectively.
2
Vertuccio, Luigi. "Nanofilled epoxy adhesive for structural aereonautic materials." Doctoral thesis, Universita degli studi di Salerno, 2017. http://hdl.handle.net/10556/2588.
Повний текст джерелаАнотація:
2015 - 2016The focus of this study is to design new nano-modified epoxy adhesives using carbon nanofillers such as carbon nanotubes, carbon nanofibers and exfoliated graphite. Kinetic analysis, transport properties, dynamic mechanical properties and electrical properties have shown to be a powerful means for understanding molecular structure and phase composition of the formulated nanocomposites. Kinetic analysis, performed by using an advanced iso-conversional method and the Kamal’s model-diffusion controlled respectively, has shown which, in epoxy resin, based on the tetrafunctional epoxy precursor N,N′-tetraglycidyl methylene dianiline-(TGMDA) hardened with 4,4-diaminodiphenyl sulfone (DDS), the introduction of the diluent decreases particularly the activation energy of secondary amine-epoxy reaction. The inclusion in the resin of one-dimensional fillers does not lead to big differences in the curing kinetics behaviour with respect to the raw epoxy. An increase in the activation energy is found in the case of highly exfoliated graphite. It is likely due to a reduction of free molecular segments of the epoxy network entrapped inside self-assembly structures. Transport properties have shown that, using a non-stoichiometric amount of hardener, the chemical structure of epoxy mixture exhibits unique properties concerning the water sorption for which the Equilibrium Concentration of Water is reduced up to a maximum of 30%. Dynamic mechanical analysis have shown that the nanoparticles are responsible of a more mobile phase, in the structure of the resin, determining an additional glass transition at lower temperature with respect to the main glass transition temperature. The fraction of the more mobile phase is strictly related to the amount and nature of the nanofiller and to the amount of the hardener, in fact, using a non-stoichiometric amount of hardener, also the electrical properties are improved further. The adhesive formulations based on epoxy/nanostructured carbon forms are used to obtain both adhesive and adherents to order to evaluate the adhesion properties with different joint configurations (tensile butt joint and single lap joint). The inclusion of carbon nanofillers inside the epoxy adhesive caused a significant improvement in the bond strength of the joints, changing the failure mode of joints in single lap joint shear tests. Finally, the conductive adhesive carbon nanotubes based, have been modified, by introduction of an elastomer, to order to obtain high performance in the configuration lap shear strength (LSS) with adherents in carbon fiber reinforced plastics (CFRP) used in aeronautic field. A correct combination of elastomer and carbon nanotubes, has allowed obtaining a conductive adhesive with high performance. [edited by author]
XV n.s. (XXIX)
3
Dabrowska, Izabela. "Polyolefin nanocomposite with different types of nanofillers." Doctoral thesis, Università degli studi di Trento, 2013. https://hdl.handle.net/11572/368488.
Повний текст джерелаАнотація:
The PhD project was details on the polyolefin nanocomposites compounding, processing and preparation. Two different types of polymer matrix with low melt flow rate for fiber forming polymers have been selected; high density polyethylene (HDPE) and isotactic polypropylene (PP). High density polyethylene was compounded with double layered hydrotalcite (LDH) while in case of polypropylene reinforcement by adding fumed silica and kaolinite was performed. In this way the influence of the nanofiller type on the thermo-mechanical properties of the prepared nanocomposites were studied.
In recent years several research efforts have been focused on the preparation of polymer/layered inorganic nanocomposites because of the excellent properties in comparison to the neat polymer. The main reason of this interest lies certainly in the properties of the nanoclay, like high stiffness, and high aspect ratio, that induce enhancement of various polymer properties (thermal stability, mechanical properties, flame resistance and gas barrier) even with small amount of filler. Moreover, nanocomposites can be processed more easily than microcomposite. Recently literature evidences a lot of progress in the nanofilled bulk materials; on the other hand, there are relatively a few publications on fibers made of nanofilled polyolefins. For instance, PP fibers were produced with various types of nanofillers, e.g. layered silicates, carbon nanotubes and montmorillonite. In the case of HDPE, composite fibers containing calcium carbonate, carbon nanotubes, silica and layered silicates were reported. It is worth to mention that so far, no publication could be found on this work using the same nanofillers with the same matrix.
This thesis is divided into six chapters; Introduction and Background, Experimental activities, after obtained Results with discussions are reported and finally Conclusions.
In the Introduction and Background (Chapter I and II) general information about nanocomposites and characteristic of different nanofillers type were summarized. After that polymer processing method with particular attention on the melt extrusion and fiber spinning were described.
Third Chapter is dedicated to the experimental part. Here, the used material characterization, nanocomposite preparation procedure and description of experimental techniques were reported. All nanocomposites were characterized by different experimental techniques. First nanofiller morphology by microscope (SEM and TEM) and X-ray diffraction technique was tested. Thermal stability was investigated by Thermal Gravimetric Analysis (TGA) and crystallization behavior by Differential Scanning Calorimetry (DSC). Finally mechanical properties were characterized by tensile test, Dynamical Mechanical Thermal Analysis (DMTA) and creep test.
The Results and Discussion have been divided into two parts; first one was dedicated to the high density polyethylene layered double hydrotalcite nanocomposites (HDPE-LDH), while in the second polypropylene with fumed silica (PP-FS) and kaolinite (PP-K) nanocomposite were described.
i. High density polyethylene hydrotalcite (HDPE-LDH) nanocomposites after different process of plates and fibers production will be compared in Chapter IV. At the beginning a polypropylene matrix, suitable for fiber production, was firstly melt compounded with organically modified hydrotalcite up to 5% by wt. Similar compositions with up to 3% wt. of LDH were performed by melt spinning. The incorporation of the clay into both bulk and fiber nanocomposite enhanced the thermal stability and induced heterogeneous nucleation of HDPE. Hydrotalcite positively affected the mechanical properties in term of higher Young’s modulus and tensile strength.
After the preliminary characterization on bulk and as-spun material the fibers were hot drawn up to draw ratio (DR) 20. XRD analysis revealed intercalation with high degree of exfoliation for the composites with 1-2% wt. of LDH. For this compositions higher elastic modulus 9.0 GPa - 9.3 GPa (with respect to 8.0 GPa of the neat HDPE), and maintain tensile strength and deformation at break were observed. Moreover, the addition of low amount of LDH significantly improved the creep stability.
ii. Nanocomposites of isotactic polypropylene fumed silica (PP-FS) were described in the Chapter V. Two types of hydrophobic fumed silica with different surface area (170m2•g-1 and 150m2•g-1) and surface treatment (treated respectively by dimethyldichlorosilane and octylsilane) up to 2% vol. were used. Similar as in case of HDPE-LDH nanocomposites plates production and characterization was a preliminary step to select the best compositions for the fiber preparation. After that, the work has been focused on the iPP-FS fiber production. Introduction of the nanofiller enhanced thermal stability and mechanical properties of the nanocomposite. Elastic modulus at draw ratio 10 increased from 5.3 GPa for neat iPP up to 7.5 – 8.6 GPa for compositions with 0.25 – 0.5% vol. Together with this improvement enhancement in strength at break and maintaining deformation at break were observed. Moreover, isothermal creep tests evidenced improvement in the creep stability due to the FS introduction, over the whole range of investigated draw ratios.
iii. The last results of recent research dedicated to the polypropylene kaolinite (PP-K) nanocomposites are reported in Appendix 1. Nanocomposite fibers were successfully spun up to draw ratio (DR) 15 at very high nanofiller content up to 30% wt. The presence of kaolinite not only increased the thermal stability but also enhanced elastic modulus up to 5.6 GPa – 7.0 GPa for compositions with 1% up to 30% wt. of kaolinite, in comparison to 5.4 GPa for neat PP at draw ratio 10. Moreover, for the composition with 10% wt. of kaolinite better drawability with maximum modulus was obtained in comparison to neat PP.
Finally the most important observation made on polyolefin nanocomposites fibers were summarized in the Chapter VI. It can be concluded that polyolefin fibers nanocomposites were successfully prepared by two different processing conditions: melt compounding and melt spinning followed by hot drawing.
In case of plates the introduction of nanosilica remarkably improved the thermal stability and elastic modulus, with retention of the pristine tensile properties at break. Nanocomposites fibers showed a higher improvement of the elastic modulus with respect to the nanocomposites plates containing the same percentage of nanofiller. Moreover, the introduction of the nanofiller enhanced tensile dynamic mechanical properties especially for higher draw ratio. Similar behavior was also observed in case of creep compliance. Higher creep stability was observed for the drawn fibers with nanofiller in comparison to neat polymer. This behavior could be a consequence of the different orientation and morphology related to the crystallinity developed in the spinning. These results confirmed that polyolefin containing nanofiller could be easily spun into nanofilled fiber. TEM images revealed how the experienced improvements of the mechanical properties could be probably related to the orientation of nanofiller aggregates along the strain direction and to the consequent increase of the filler-matrix interfacial area.
4
Dabrowska, Izabela. "Polyolefin nanocomposite with different types of nanofillers." Doctoral thesis, University of Trento, 2013. http://eprints-phd.biblio.unitn.it/1103/1/Izabela_Dabrowska_PhD_Thesis.pdf.
Повний текст джерелаАнотація:
The PhD project was details on the polyolefin nanocomposites compounding, processing and preparation. Two different types of polymer matrix with low melt flow rate for fiber forming polymers have been selected; high density polyethylene (HDPE) and isotactic polypropylene (PP). High density polyethylene was compounded with double layered hydrotalcite (LDH) while in case of polypropylene reinforcement by adding fumed silica and kaolinite was performed. In this way the influence of the nanofiller type on the thermo-mechanical properties of the prepared nanocomposites were studied.
In recent years several research efforts have been focused on the preparation of polymer/layered inorganic nanocomposites because of the excellent properties in comparison to the neat polymer. The main reason of this interest lies certainly in the properties of the nanoclay, like high stiffness, and high aspect ratio, that induce enhancement of various polymer properties (thermal stability, mechanical properties, flame resistance and gas barrier) even with small amount of filler. Moreover, nanocomposites can be processed more easily than microcomposite. Recently literature evidences a lot of progress in the nanofilled bulk materials; on the other hand, there are relatively a few publications on fibers made of nanofilled polyolefins. For instance, PP fibers were produced with various types of nanofillers, e.g. layered silicates, carbon nanotubes and montmorillonite. In the case of HDPE, composite fibers containing calcium carbonate, carbon nanotubes, silica and layered silicates were reported. It is worth to mention that so far, no publication could be found on this work using the same nanofillers with the same matrix.
This thesis is divided into six chapters; Introduction and Background, Experimental activities, after obtained Results with discussions are reported and finally Conclusions.
In the Introduction and Background (Chapter I and II) general information about nanocomposites and characteristic of different nanofillers type were summarized. After that polymer processing method with particular attention on the melt extrusion and fiber spinning were described.
Third Chapter is dedicated to the experimental part. Here, the used material characterization, nanocomposite preparation procedure and description of experimental techniques were reported. All nanocomposites were characterized by different experimental techniques. First nanofiller morphology by microscope (SEM and TEM) and X-ray diffraction technique was tested. Thermal stability was investigated by Thermal Gravimetric Analysis (TGA) and crystallization behavior by Differential Scanning Calorimetry (DSC). Finally mechanical properties were characterized by tensile test, Dynamical Mechanical Thermal Analysis (DMTA) and creep test.
The Results and Discussion have been divided into two parts; first one was dedicated to the high density polyethylene layered double hydrotalcite nanocomposites (HDPE-LDH), while in the second polypropylene with fumed silica (PP-FS) and kaolinite (PP-K) nanocomposite were described.
i. High density polyethylene hydrotalcite (HDPE-LDH) nanocomposites after different process of plates and fibers production will be compared in Chapter IV. At the beginning a polypropylene matrix, suitable for fiber production, was firstly melt compounded with organically modified hydrotalcite up to 5% by wt. Similar compositions with up to 3% wt. of LDH were performed by melt spinning. The incorporation of the clay into both bulk and fiber nanocomposite enhanced the thermal stability and induced heterogeneous nucleation of HDPE. Hydrotalcite positively affected the mechanical properties in term of higher Young’s modulus and tensile strength.
After the preliminary characterization on bulk and as-spun material the fibers were hot drawn up to draw ratio (DR) 20. XRD analysis revealed intercalation with high degree of exfoliation for the composites with 1-2% wt. of LDH. For this compositions higher elastic modulus 9.0 GPa - 9.3 GPa (with respect to 8.0 GPa of the neat HDPE), and maintain tensile strength and deformation at break were observed. Moreover, the addition of low amount of LDH significantly improved the creep stability.
ii. Nanocomposites of isotactic polypropylene fumed silica (PP-FS) were described in the Chapter V. Two types of hydrophobic fumed silica with different surface area (170m2•g-1 and 150m2•g-1) and surface treatment (treated respectively by dimethyldichlorosilane and octylsilane) up to 2% vol. were used. Similar as in case of HDPE-LDH nanocomposites plates production and characterization was a preliminary step to select the best compositions for the fiber preparation. After that, the work has been focused on the iPP-FS fiber production. Introduction of the nanofiller enhanced thermal stability and mechanical properties of the nanocomposite. Elastic modulus at draw ratio 10 increased from 5.3 GPa for neat iPP up to 7.5 – 8.6 GPa for compositions with 0.25 – 0.5% vol. Together with this improvement enhancement in strength at break and maintaining deformation at break were observed. Moreover, isothermal creep tests evidenced improvement in the creep stability due to the FS introduction, over the whole range of investigated draw ratios.
iii. The last results of recent research dedicated to the polypropylene kaolinite (PP-K) nanocomposites are reported in Appendix 1. Nanocomposite fibers were successfully spun up to draw ratio (DR) 15 at very high nanofiller content up to 30% wt. The presence of kaolinite not only increased the thermal stability but also enhanced elastic modulus up to 5.6 GPa – 7.0 GPa for compositions with 1% up to 30% wt. of kaolinite, in comparison to 5.4 GPa for neat PP at draw ratio 10. Moreover, for the composition with 10% wt. of kaolinite better drawability with maximum modulus was obtained in comparison to neat PP.
Finally the most important observation made on polyolefin nanocomposites fibers were summarized in the Chapter VI. It can be concluded that polyolefin fibers nanocomposites were successfully prepared by two different processing conditions: melt compounding and melt spinning followed by hot drawing.
In case of plates the introduction of nanosilica remarkably improved the thermal stability and elastic modulus, with retention of the pristine tensile properties at break. Nanocomposites fibers showed a higher improvement of the elastic modulus with respect to the nanocomposites plates containing the same percentage of nanofiller. Moreover, the introduction of the nanofiller enhanced tensile dynamic mechanical properties especially for higher draw ratio. Similar behavior was also observed in case of creep compliance. Higher creep stability was observed for the drawn fibers with nanofiller in comparison to neat polymer. This behavior could be a consequence of the different orientation and morphology related to the crystallinity developed in the spinning. These results confirmed that polyolefin containing nanofiller could be easily spun into nanofilled fiber. TEM images revealed how the experienced improvements of the mechanical properties could be probably related to the orientation of nanofiller aggregates along the strain direction and to the consequent increase of the filler-matrix interfacial area.
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McGlasson, Alex M. "Quantification of the Dispersion of Reinforcing Fillers in Polymer Nanocomposite Materials." University of Cincinnati / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1554475356053017.
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Al, Habis Nuha. "Engineering and Modeling Carbon Nanofiller-Based Scaffolds for Tissue Regeneration." University of Dayton / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1500561556157495.
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7
Vilà, Ramírez Narciso. "Effects of melt blended poss nanofillers on pom and ABS thermal stability." Doctoral thesis, Universitat Politècnica de Catalunya, 2014. http://hdl.handle.net/10803/145685.
Повний текст джерелаАнотація:
This PhD thesis investigated the incorporation of Polyhedral Oligomeric Silsesquioxanes (POSS) in thermoplastic base materials via melt-blending procedures.
Particularly, a focus is taken on the enhancement of the thermal resistance through the addition of different types of POSS on two popular engineering plastics known by their low thermal stability, one being a semi-crystalline copolymer i.e. polyoxymethylene (POM) and the other an amorphous copolymer i.e. acrylonitrile butadiene styrene grafted with maleic anhydride (ABS-g-Ma). Different nanocomposites have been produced, from which its morphology, miscibility, structure, thermal properties and appearance behaviour before and during the thermoxidative degradation is herein quantified and discussed together with the resulting benefits and drawbacks.
All the nanocomposites have been produced via melt-blending, using the nanofillers Glycidyl, Glycidyl-Isobutyl, Aminopropyl-isobutyl and Poly(ethylene-glycol) for the POM matrix, and Amino-Propyl Isobutyl, Glycidyl, and Trisilanol for the ABS-g-Ma matrix.
The incorporation adequacy of the nanofillers into the matrix has been pre-assessed with the Hoy¿s solubility calculation method and later on corroborated with scanning electron microscopy (SEM) and differential scanning calorimetry (DSC). The quantification of the thermal degradation behaviour of each sample at different temperatures and exposure times was carried out through Fourier transform infrared spectrography (FTIR), thermogravimetric analysis (TGA) including the degradation kinetics and, ultimately, the sample appearance progress has been assessed in terms of yellowing by means of colour spectrophotometry (Cielab).
The results showed that the presence of different POSS's used with the POM matrix improves dramatically the thermal stability of the base material and that such improvement is proportionate to the solubility compatibility between matrix and the nanofiller. The best performance was found with Aminopropyl-isobutyl, whereby the temperature of maximum rate of degradation (TMAX) increased by 22ºC. Said improvement is also seen in the conditions at which the nanocomposite developed only 2% of carbonyl yield and 8% of yellowing compared to the standard POM copolymer, which is taken as the base reference with 100% deterioration suffered in the above two indicators.
However, the performance of the different nanocomposites produced in this work with ABS-g-Ma has not been as encouraging as the POM-based nanocomposites described above. Although the SEM morphological analysis show adequate incorporation and miscibility of the nanofillers into the matrix, the GPOSS and the TPOSS nanocomposites provided no relevant improvements in thermal stability when compared to the base ABS-g-Ma, and the APOSS blend exhibits a very slight decay in almost all the quantitative analysis carried out in this work.Los avances producidos en años recientes en el campo de la nanotecnología y sus aplicaciones en los materiales están aportando grandes mejoras en el rendimiento de los mismos en áreas como la resistencia mecánica, estabilidad térmica, propiedades ópticas y eléctricas, entre otras. Por otro lado, el mundo de la ingeniería y el diseño de componentes plásticos está llevando los materiales cada vez más a su límite, con el fin de poder ofrecer el máximo rendimiento al mínimo coste. Esta realidad implica la necesidad creciente de customizar estructuras poliméricas con propiedades mejoradas en áreas específicas para cada aplicación. A pesar de los desarrollos que se han estado produciendo últimamente en nanocompuestos termoplásticos, el conocimiento en este campo es aún limitado, y requiere de más iniciativas de investigación y desarrollo sobre el amplio campo de posibilidades que nos ofrecen los nanocompuestos. El objetivo de esta tesis es contribuir en el conocimiento de los nanocompuestos a través del estudio de los efectos de varias nanocargas del tipo Polyhedral Oligomeric Silsesquioxanes (POSS) en el comportamiento de la resistencia térmica del copolímero semicristalino polióxido de metileno (POM) y del terpolímero amorfo acrilonitrilo‐butadieno‐estireno (ABS), los cuales son dos plásticos técnicos susceptibles a la termoxidación. Diferentes nanocompuestos se han elaborado con el fin de estudiar su morfología, miscibilidad, estructura, propiedades térmicas y apariencia, así como los beneficios y contrapartidas que resultan de ellos. Los nano‐compuestos han sido elaborados mediante el método de mezcla en estado fundido (melt‐blending), utilizando cuatro nano‐cargas distintas para el POM, siendo Glicidil, Glicidil‐Isobutil, Aminopropil‐isobutil y Poli(etilen‐glicol), y tres nano‐cargas para el ABS, siendo Amino‐Propil Isobutil, Glicidil y Trisilanol La compatibilidad teórica de las nano‐cargas se ha calculado mediante el método de solubilidad de “Hoy”, y se ha corroborado con microscopia electrónica de barrido (SEM) y calorimetría diferencial de barrido (DSC). Posteriormente, cada material base y sus distintas variantes de nano‐compuestos se han sometido a diferentes condiciones de termo‐oxidación en términos de temperatura y tiempo de exposición. El comportamiento a la degradación de cada muestra se ha cuantificado mediante los métodos de espectroscopia de infrarrojos por transformada de Fourier (FTIR), análisis de termogravimetría (TGA) incluyendo cinética de degradación, y finalmente mediante espectrofotometría (Cielab) para definir el progreso de la apariencia de la muestra en términos de amarilleamiento. Los resultados derivados de la inclusión de los diferentes POSS utilizados en la matriz de POM han mejorado sustancialmente la estabilidad térmica del mismo, y dicha mejora es proporcional a la compatibilidad de solubilidades entre el POM y los POSS utilizados. El mejor comportamiento se produce con la incorporación de la nanocarga aminopropilisobutil, con una temperatura de máxima degradación (TMAX) incrementada en 22 ºC sobre la TMAX del POM original tomado como referencia. Esta mejora se refleja también con una reducción muy notable en la formación grupos carbonilo y en el amarilleamiento sufrido en la superficie de la muestra, siendo un 2% y 8% respectivamente comparados con los resultados obtenidos con la muestra equivalente del material POM original. En referencia a los nanocompuestos basados en ABS‐g‐Ma, a pesar de la adecuada solubilidad teórica entre la matriz y las diferentes nano‐cargas, así como la buena miscibilidad obtenida en la elaboración de las muestras y evidenciada en el análisis morfológico SEM, no se han podido obtener mejoras en términos de estabilidad térmica. Concretamente, la adición de GPOSS y TPOSS no han aportado beneficios relevantes en las propiedades del nanocompuesto final, y la nanocarga APOSS ha incluso afectado negativamente a la matriz con una ligera caída de la resistencia térmica.
Els avenços produïts en els últims anys tant en el camp de la nanotecnología com en les seves aplicacions en els materials, està contribuint en la millora del rendiment dels mateixos en àeras com la resistència mecànica, l’estabilitat tèrmica, i les propietats òptiques i elèctriques entre d’altres. Per altra banda, el món de l’enginyería i el disseny de components plàstics està portant els materials cada vegada més al seu límit amb la finalitat de poder oferir el màxim rendiment al mínim cost, i això comporta una necessitat creixent de customitzar les estructura polimèriques amb propietats especificament millorades en àreas molt concretes en funció de l’aplicació requerida. A pesar del desenvolupament que s’ha estat produint últimament en l’àrea de nanocompostos plàstics, el coneixement en aquest camp és encara limitat, i requereix de més iniciatives d’investigació per cobrir el potencial que ofereix aquesta classe de materials, així com conèixer també les seves limitacions. L’objectiu d’aquesta tesi es el de contribuïr en l’enteniment dels nanocompostos plàstics a través de l’estudi dels efectes de vàries nanocàrregues del tipus Polyhedral Oligomeric Silsesquioxanes (POSS) en el comportament de la resistència tèrmica del poli(òxid de metilè) (POM) com a material semicristalí, i l’acrilonitril‐butadiè‐estirè (ABS) com a material amorf. Val a dir que la selecció d’aquests dos polímers tècnics ha estat en part motivada per la seva susceptibilitat inherent a la termodegradació. Diferents nanocompostos basats amb aquests materials s’han elaborat amb la finalitat d’estudiar la seva morfología, miscibilitat, estructura, propietats tèrmiques i aparença, així com els beneficis i contrapartides que resulten d’ells. La preparació dels nanocompostos ha sigut mitjançant el mètode de barreja en estat fos (melt‐blending), util.litzant quatre nano‐càrregues diferentes per el POM, siguent glicidil, glicidil‐Isobutil, aminopropil‐isobutil y poli(etilenè‐glicol), i tres nano‐càrregues per el ABS, siguent amino‐propil isobutil, glicidil i trisilanol. La compatibilitat teòrica de les nano‐càrregues s’ha calculat mitjançant el mètode de solubitat de “Hoy”, i s’ha corroborat amb microscopia electrònica d’escombrat (SEM) i calorimetría diferencial d’escombrat (DSC). Posteriorment s’ha sotmès cada material base i les seves diferents variants de nanocompostos a diferents condicions de termo‐oxidació en termes de temperatura i temps d’exposició. El comportament a la degradació de cada mostra s’ha quantificat mitjançant els mètodes d’espectroscopía d’infraroigs per transformada de Fourier (FTIR), anàlisis de termogravimetría (TGA) incloent cinemàtica de degradació, i finalment mitjançant espectrofotometría (Cielab) per a definir el progrés de l’aparença de la mostra en termes d’engroguiment. Els resultats han mostrat, per una banda, que la inclusió dels diferents POSS util.litzats en la matriu de POM ha millorat substancialment l’estabilitat tèrmica del mateix, i aquesta millora és proporcional a la compatibilitat entre les solubitats del POM i del POSS. El millor comportament s’ha produït amb l’adició de la nano‐càrrega d’aminopropilisobutil, amb una temperatura de màxima degradació (TMAX) millorada en 22ºC en relació a la obtinguida amb la matriu de POM. Aquesta millora també es reflexa amb una reducció molt notable en la formació de grups carbonil i en l’engroguiment sofert en la superfície de la mostra, siguent un 2% i 8% respectivament comparats amb els resultats obtinguts amb la mostra equivalent del material POM original. En contrast, els nanocompostos basats en ABS‐g‐Ma no han ofert millores en termes d’estabilitat tèrmica, a pesar d’una adequada solubitat teòrica entre la matriu i les diferents nano‐càrregues util.litzades, així com la bona miscibilitat obtinguda en l’elaboració de les mostres i posteriorment evidenciada en l’anàlisi morfològic SEM. Concretament l’adició de GPOSS i de TPOSS no han aportat beneficis en les propietats del nanocompostos final, i la nano‐càrrega APOSS ha afectat negativament a la matriu amb una lleuguera caiguda de la resistència tèrmica
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DE, BIASI MATTEO. "Study of applied nanostructured and conventional dental materials." Doctoral thesis, Università degli Studi di Trieste, 2016. http://hdl.handle.net/11368/2908084.
Повний текст джерелаАнотація:
Composite resins are the most modern, widespread, aesthetic and conservative materials in the field of direct restorative dentistry. During the last years, the manufacturers of dental materials have launched onto the market composite resins with inorganic nanofillers with diameter less than 100 nm. These materials are considered nowadays the state of the art in terms of filler formulation. Nanofilled and nanohybrid composite resins have been introduced fairly recently in the clinical practice, so that there is less information about their properties and clinical effectiveness in comparison to traditional materials. The present work of thesis examined in both the laboratory and clinical setting the performance of several composite resins with nanofillers. The following items were analysed in five different phases:
1) roughness and microhardness of nanohybrid composites;
2) sealing ability of a nanohybrid flowable composite;
3) influence of finish line on the marginal seal of nanohybrid composite crowns after periodontal scaling;
4) two-year in vitro and in vivo evaluation of surface roughness of a flowable nanohybrid composite;
5) clinical effectiveness of nanofilled and nanohybrid composite resins: a systematic review.
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Rudolf, Christopher Charles. "Microstructure and Mechanical Properties of Nanofiller Reinforced Tantalum-Niobium Carbide Formed by Spark Plasma Sintering." FIU Digital Commons, 2016. http://digitalcommons.fiu.edu/etd/2596.
Повний текст джерелаАнотація:
Ultra high temperature ceramics (UHTC) are candidate materials for high temperature applications such as leading edges for hypersonic flight vehicles, thermal protection systems for spacecraft, and rocket nozzle throat inserts due to their extremely high melting points. Tantalum and Niobium Carbide (TaC and NbC), with melting points of 3950°C and 3600°C, respectively, have high resistivity to chemical attack, making them ideal candidates for the harsh environments UHTCs are to be used in. The major setbacks to the implementation of UHTC materials for these applications are the difficulty in consolidating to full density as well as their low fracture toughness. In this study, small amounts of sintering additive were used to enhance the densification and Graphene Nanoplatelets (GNP) were dispersed in the ceramic composites to enhance the fracture toughness. While the mechanisms of toughening of GNP addition to ceramics have been previously documented, this study focused on the anisotropy of the mechanisms. Spark plasma sintering was used to consolidate both bulk GNP pellets and near full relative density TaC-NbC ceramic composites with the addition of both sintering aid and GNP and resulted in an aligned GNP orientation perpendicular to the SPS pressing axis that allowed the anisotropy to be studied. In situ high load indentation was performed that allowed real time viewing of the deformation mechanisms for enhanced analysis. The total energy dissipation when indenting the bulk GNP pellet in the in-plane GNP direction was found to be 270% greater than in the out-of-plane orientation due to the resulting deformation mechanisms that occurred. In GNP reinforced TaC-NbC composites, the projected residual damaged area as a result of indentation was 89% greater when indenting on the surface of the sintered compact (out-of-plane GNP orientation) than when indenting in the orthogonal direction (in-plane GNP orientation) which is further evidence to the anisotropy of the GNP reinforcement.
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Figueiredo, Viviane Maria Gonçalves de. "Efeito de nanofilmes depositados a plasma na resistência de união de um cimento resinoso a uma cerâmica à base de zircônia /." São José dos Campos, 2014. http://hdl.handle.net/11449/127607.
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Orientador: Lafayette Nogueira JúniorCo-orientador: Marcos Massi
Banca: Renato Sussumu Nishioka
Banca: Argemiro Soares da Silva Sobrinho
Banca: Eron Toshio Colauto Yamamoto
Banca: Rubens Nisei Tango
Resumo: Esta pesquisa objetivou avaliar o efeito de diferentes nanofilmes depositados a plasma na resistência de união entre cimento resinoso e cerâmica à base de zircônia. 120 blocos/espécimes (15,2 x 12,5 x 1,7 mm) e 18 discos (11,0 x 1,4 mm) de zircônia (Y-TZP) (VITA In-Ceram Zirconia, Vita Zahnfabrik, Alemanha) receberam diferentes tratamentos de superfície (n = 20 para os blocos) (n = 3 para discos): zircônia sem tratamento (Zrpolida), jateamento de alumina revestida por sílica (30 μm) (Zrjat#), nanofilme à base de sílica (ZrSiO2), jateamento de alumina (45 μm) + nanofilme à base de sílica (Zrjat+SiO2), e nanofilme à base de fluoreto (ZrF) e jateamento de alumina (45 μm) + nanofilme à base de fluoreto (Zrjat+F). Os nanofilmes foram depositados por meio da técnica a plasma PECVD. As superfícies cerâmicas foram caracterizadas pela morfologia (MEV e MFA), química (XPS) e molhabilidade (ângulo de contacto), realizada nos discos. O agente de união silano foi aplicado em cada superfície e um cilindro de cimento resinoso foi construído sobre os espécimes tratados. Metade dos espécimes de cada grupo (n = 10) foram submetidos a 6.000 ciclos térmicos. A resistência de união foi avaliada pelo teste de cisalhamento e análise fractográfica pelo estereomicroscópico, MEV e EDS. Para análise estatística utilizou-se ANOVA 1-Fator e o teste de Tukey, para presença e ausência de envelhecimento (p = 0,05). A zircônia apresentou-se mais hidrofílica após a deposição dos nanofilmes. Ligações químicas entre Si-O foram encontradas em ZrSiO2; ZrF promove um processo de fluoração na superfície da cerâmica Y-TZP, convertendo-a em oxifluoreto de zircônio. Os valores de resistência de união iniciais obtidos pelos tratamentos de superfície a plasma não superaram os valores de união da silicatização. Após o envelhecimento, todas as amostras do grupo ZrSiO2(TC) sofreram falhas pré-teste. OS valores de resistência de....
Abstract: This study aimed to evaluated the effects of differents plasma nanofilms on the bond strength between resin cement and zirconia ceramic. 120 blocks / specimens (15.2 x 12.5 x 1.7 mm) and 18 discs (11.0 x 1.4 mm) of zirconia (Y-TZP) (VITA In-Ceram Zirconia, Vita Zahnfabrik, Germany) received differents treatments surface (n = 20 for the blocks) (n = 3 for discs): untreated zirconia (Zrpolida), silica-coated (30 μm) (Zrjat#), silica nanofilm (ZrSiO2), sandblasted by air-borne particle abrasion with aluminum oxide particles (45 μm) + silica nanofilm (Zrjat+SiO2) and fluoride nanofilm (ZrF) and sandblasted by air-borne particle abrasion with aluminum oxide particles (45 μm) + fluoride nanofilm (Zrjat+F). The nanofilms were deposited by PECVD technique of the plasma. The ceramic surfaces were characterized by morphology (SEM and AFM), chemical (XPS) and wettability (Contact angle), that was performed on discs. The silane agent was applied to each surface treatment and a cylinder of resin cement was built on the specimens. Half of the samples of each group (n = 10) were subjected to 6.000 thermalcycles. The bond strength was evaluated by shear test and fractographic analysis by stereoscopic, SEM and EDS. Statistical analysis was performed using one-way ANOVA and Tukey's test for the presence and absence non-aged (p = 0.05). Zirconia presented more hydrophilic after nanofilms deposition. Chemical bonds between Si-O were found in ZrSiO2; ZrF promotes a process of fluorination on the Y-TZP surface, promoting the conversion of zirconia in zirconium oxyfluoride. The initial values of bond strength obtained by plasma treatment did not exceed the bond values of the silica-coated. After aging, all samples of the group ZrSiO2 (TC) falied. The values of bond strength of ZrF (TC) (3.8 MPa) were lower than Zrjat# (TC) (15.4 MPa) and Zrpolida (TC) (6.3 MPa). The silica nanofilm showing detachment after shearing. Adhesive failures were predominant among the...
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Книги з теми "NANOFILLER MATERIAL"
1
Polymer Composites With Carbonaceous Nanofillers Propterties And Applications. Wiley-VCH Verlag GmbH, 2012.
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2
Thomas, Sabu, Nandakumar Kalarikkal, Hanna J. Maria, Srinivasarao Yaragalla, and Raghavendra Kumar Mishra. Carbon Based Nanofillers and Their Rubber Nanocomposites: Fundamentals and Applications. Elsevier, 2019.
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3
Thomas, Sabu, Nandakumar Kalarikkal, Raghvendra Kumar Mishra, Hanna J. Maria, and Srinivasarao Yaragalla. Carbon-Based Nanofillers and Their Rubber Nanocomposites: Carbon Nano-Objects. Elsevier, 2018.
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4
Thomas, Sabu, Nandakumar Kalarikkal, Hanna J. Maria, Srinivasarao Yaragalla, and Raghavendra Kumar Mishra. Carbon Based Nanofillers and Their Rubber Nanocomposites: Synthesis, Characterization and Applications. Elsevier, 2018.
Знайти повний текст джерелаЧастини книг з теми "NANOFILLER MATERIAL"
1
Chen, D., and L. Zhang. "Harmonic Vibration of Inclined Porous Nanocomposite Beams." In Lecture Notes in Civil Engineering, 497–501. Singapore: Springer Nature Singapore, 2023. http://dx.doi.org/10.1007/978-981-99-3330-3_52.
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AbstractThis work investigated the linear harmonic vibration responses of inclined beams featured by closed-cell porous geometries where the bulk matrix materials were reinforced by graphene platelets as nanofillers. Graded and uniform porosity distributions combined with different nanofiller dispersion patterns were applied in the establishment of the constitutive relations, in order to identify their effects on beam behavior under various harmonic loading conditions. The inclined beam model comprised of multiple layers and its displacement field was constructed using Timoshenko theory. Forced vibration analysis was conducted to predict the time histories of mid-span deflections, considering varying geometrical and material characterizations. The findings may provide insights into the development of advanced inclined nanocomposite structural components under periodic excitations.
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Jastrzębska, M., and M. Rutkowska. "Material Model of Polyester Composites with Glass Reinforced Polyester Recyclate and Nanofiller." In Science and Technology of Polymers and Advanced Materials, 35–45. Includes bibliographical references and index.: Apple Academic Press, 2019. http://dx.doi.org/10.1201/9780429425301-3.
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Mohan, T. P., and K. Kanny. "Green Nanofillers for Polymeric Materials." In Green Nanomaterials, 99–138. Singapore: Springer Singapore, 2020. http://dx.doi.org/10.1007/978-981-15-3560-4_5.
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Mikhail, Sarah S., Shereen S. Azer, and Scott R. Schricker. "Nanofillers in Restorative Dental Materials." In Handbook of Nanomaterials Properties, 1377–442. Berlin, Heidelberg: Springer Berlin Heidelberg, 2014. http://dx.doi.org/10.1007/978-3-642-31107-9_58.
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Boonmahitthisud, Anyaporn, Anyaporn Boonmahitthisud, Saowaroj Chuayjuljit, and Takaomi Kobayashi. "Encapsulation of Inorganic Renewable Nanofiller." In Handbook of Composites from Renewable Materials, 143–64. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2017. http://dx.doi.org/10.1002/9781119441632.ch68.
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Kodal, Mehmet, and Guralp Ozkoc. "Micro and Nanofillers in Rubbers." In Advanced Structured Materials, 303–56. Berlin, Heidelberg: Springer Berlin Heidelberg, 2013. http://dx.doi.org/10.1007/978-3-642-20925-3_11.
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Dasgupta, Debarshi, Alok Sarkar, Dieter Wrobel, and Anubhav Saxena. "Insights on Nanofiller Reinforced Polysiloxane Hybrids." In Novel Nanoscale Hybrid Materials, 179–200. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2018. http://dx.doi.org/10.1002/9781119156253.ch5.
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Burgaz, Engin. "PU Rigid Nanocomposite Foams Containing Cylindrical Nanofillers." In Advanced Structured Materials, 165–232. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-19558-8_4.
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Burgaz, Engin. "PU Rigid Nanocomposite Foams Containing Spherical Nanofillers." In Advanced Structured Materials, 233–89. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-19558-8_5.
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Ghose, Subrata, K. A. Watson, D. M. Delozier, D. C. Working, John W. Connell, J. G. Smith, Y. P. Sun, and Y. Lin. "Thermal Conductivity of Polyimide/Carbon Nanofiller Blends." In Advances in Composite Materials and Structures, 749–52. Stafa: Trans Tech Publications Ltd., 2007. http://dx.doi.org/10.4028/0-87849-427-8.749.
Повний текст джерелаТези доповідей конференцій з теми "NANOFILLER MATERIAL"
1
Ghazzawi, Sultan M., and Tyler N. Tallman. "On the Development of a Concentric Cylindrical Model for the Deformation-Dependent Electrical Resistivity of Fiber-Reinforced Composites." In ASME 2022 Conference on Smart Materials, Adaptive Structures and Intelligent Systems. American Society of Mechanical Engineers, 2022. http://dx.doi.org/10.1115/smasis2022-89142.
Повний текст джерелаАнотація:
Abstract Sectors such as the aerospace, civil, and automotive industries have experienced increasing demands and applications of fiber-reinforced composites. However, due to their nature of complex and often outwardly invisible failure modes, monitoring fiber-reinforced composites by non-destructive means is important. One way of monitoring these materials is by integrating self-sensing capabilities into the composites through nanofiller modification in order to make use of the piezoresistive effect. In this approach, changes in electrical resistivity are a function of mechanical strains, thereby allowing for intrinsic self-sensing. So far, predictive modeling work in this area has focused predominantly on microscale piezoresistivity. Much less work has considered the effect of the continuous fiber reinforcement, and research on achieving meaningful analytical predictions of resistivity changes in fiber-matrix material systems has been limited. Therefore, to overcome this gap, an analytical model that allows for predicting changes in the resistivity of a material system consisting of both a nanofiller-modified polymer phase and a continuous fiber reinforcement phase is presented. This approach is predicated on the development of an electrical concentric cylindrical model. We start by identifying our analysis domain: concentric cylinders representing a continuous reinforcing fiber surrounded by the nanofiller-modified matrix. Then, by enforcing the law of conservation of electrical charge and by utilizing existent piezoresistivity relations for the nanofiller-modified matrix, the system is homogenized in order to predict the change in the resistivity of the concentric cylinder as a function of applied strains and constituent properties. It is hoped that this preliminary result will be an important building block towards the development of a laminate theory of piezoresistivity.
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Jain, Rajan, Hashim Hassan, Weinong Chen, Tyler N. Tallman, and Nesredin Kedir. "Electrical Self-Sensing of Pulsed Laser Ablation in Nanofiller-Modified Composites." In ASME 2021 Conference on Smart Materials, Adaptive Structures and Intelligent Systems. American Society of Mechanical Engineers, 2021. http://dx.doi.org/10.1115/smasis2021-67779.
Повний текст джерелаАнотація:
Abstract Laser-to-composite interactions are becoming increasingly common in diverse applications such as diagnostics, fabrication and machining, and weapons systems. Despite a lack of physical contact, lasers can induce seemingly imperceptible structural damage to materials. In safety-critical venues like aerospace, automotive, and civil infrastructure where composites are playing an increasingly prominent role, it is desirable to have means of sensing laser exposure on a composite material. Self-sensing materials may be a powerful method of addressing this need. Herein, we present an initial exploratory study on the potential of using changes in electrical measurements as a way of detecting laser exposure to a carbon nanofiber (CNF)-modified glass fiber/epoxy laminate. CNFs were dispersed in liquid epoxy resin prior to laminate fabrication via hand layup. The dispersed CNFs form a three-dimensional conductive network which allows for electrical measurements to be taken from the traditionally insulating glass fiber/epoxy material system. It is expected that damage to the network will disrupt the electrical pathways, thereby causing the material to exhibit slightly higher resistance. To test laser sensing capabilities, a resistance baseline of the CNF-modified glass fiber/epoxy was first established before laser exposure. The specimens were then exposed to an infra-red laser operating at 1064 nm, 35 kHz, and pulse duration of 8.2 ns. The specimens were irradiated for a total of 20 seconds (4 exposures each at 5 seconds). The resistances of the specimens were then measured again post-ablation. It was found that the average resistance increased by about 18 percent. This established that the laser was indeed causing damage to the specimen sufficient to evoke a change in electrical properties. To expand on this result, electrical impedance tomography (EIT) was employed for localization of 1, 3, and 5-second laser exposure on a larger specimen. EIT was not only successful in detecting damage that was virtually imperceptible to the human-eye, but it also accurately localized the exposure sites. The post-ablation conductivity of the exposure sites decreased in a manner that was comparable to the resistance increases obtained during prior resistance change testing. Based on this preliminary study, this research could lead to the development of a real-time exposure detection and tracking system for the measurement, fabrication, and defense industries.
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Santoso, Henry, Andrea Cavallini, and Suwarno. "The Effect of Nanofiller And Temperature on Dielectric Properties of Polypropylene-Based Dielectric Material." In 2020 IEEE International Conference on Power and Energy (PECon). IEEE, 2020. http://dx.doi.org/10.1109/pecon48942.2020.9314466.
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Kurimoto, Muneaki, Takahiro Umemoto, Shigeyoshi Yoshida, Takahiro Mabuchi, and Hirotaka Muto. "Influence of Nanofiller Material on Impulse Breakdown Strength of Epoxy Nanocomposite without Micrometer-size Agglomerates." In 2020 IEEE Conference on Electrical Insulation and Dielectric Phenomena (CEIDP). IEEE, 2020. http://dx.doi.org/10.1109/ceidp49254.2020.9437523.
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Kamble, Mithil, Aniruddha Lakhnot, Catain Picu, and Nikhil Koratkar. "Hierarchically Organized Nanocomposites for Enhanced Fatigue Life of Rotorcraft Components." In Vertical Flight Society 75th Annual Forum & Technology Display. The Vertical Flight Society, 2019. http://dx.doi.org/10.4050/f-0075-2019-14722.
Повний текст джерелаАнотація:
Rotorcraft components, which are often made with reinforced fiber composites, are subjected to severe fatigue loadings due to increased performance demands. Therefore, considerable research interest exists in improving fatigue life of conventional fiber reinforced composites. Nanocomposites are a new class of materials which seek to improve mechanical performance of materials by creating nanoscale crack-nanofiller interactions. In this study we demonstrate the fatigue life improvement of conventional composites by addition of SiO2 nanofillers. The epoxy resin was initially modified with nanofillers to test the static fracture toughness. Once the improvement in static facture toughness was confirmed, three phase modified fiber reinforced composites were made using the modified resin. Cyclic tests were performed at various stress level which demonstrate that three phase nanocomposites perform better than conventional fiber reinforced composites. Fractographic analysis suggests that nanofiller de-bonding from the matrix as well as crack deflection around nanofiller clusters contributes to the improved fracture toughness and fatigue life.
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Abdel Hamid, Dalia, Amal Esawi, Inas Sami, and Randa Elsalawy. "Characterization of Nano- and Micro-Filled Resin Composites Used as Dental Restorative Materials." In ASME 2008 2nd Multifunctional Nanocomposites and Nanomaterials International Conference. ASMEDC, 2008. http://dx.doi.org/10.1115/mn2008-47053.
Повний текст джерелаАнотація:
Adhesively-bonded resin composites have the advantage of conserving sound tooth structure with the potential for tooth reinforcement, while at the same time providing an aesthetically acceptable restoration. However, no composite material has been able to meet both the functional needs of posterior restorations and the superior aesthetics required for anterior restoration. In an attempt to develop a dental resin composite that had the mechanical strength of hybrid composite materials and the superior polish and gloss retention associated with microfilled materials, nanofilled resin composites have been introduced in the market. Although nanofillers are the most popular fillers utilized in current visible light-activated dental resin composites and are claimed to be the solution for the most challenging material limitations as a universal restorative material, the mechanisms by which these fillers influence the resin composite properties are not well explained. In this study, some physical and mechanical properties of a nanofilled resin composite containing 60 vol. % zirconia and silica fillers were evaluated and compared to those of a microhybrid resin composite of the same composition. The nanofilled resin composite was found to have equivalent polymerization shrinkage and depth of cure to the microhybrid material but a slightly lower degree of conversion and density. Regarding mechanical behaviour, although the nanocomposite was found to exhibit significantly higher wear resistance, and equivalent flexural strength, its indentation modulus and nanohardness were slightly lower. Field-emission scanning electron microscopy (FE-SEM) analysis was conducted in order to evaluate the microstructure and to obtain a better understanding of the effect of the nanofillers on the behaviour of the nanocomposite.
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Yekani Fard, Masoud, Alek Pensky, and Jack Mester. "Nanoscale Interphase Characterization of Agglomerated MWCNT in Composites Connected to Mode I Fracture." In ASME 2020 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/imece2020-23635.
Повний текст джерелаАнотація:
Abstract The authors investigate the effect of carbon nanotubes (CNT) on the microstructure, nanomechanical properties, and fracture performance of three-phase polymer matrix composites (PMC). Two types of carbon fiber (CF)-Epoxy-CNT composites with different nanofiller distribution were studied at the nanoscale with PeakForce Quantitative Nanomechanical mapping technique (PFQNM) and macroscale with mode I fracture testing to clarify the relationship between nanofiller interphase properties and mode I fracture performance. CNT agglomerates were identified on the polished sample surface in well-dispersed and agglomerated form. AFM data showed the inhomogeneity of nanoscale local mechanical properties in CNT-rich zones. Variation in material properties is attributed to voids, CNT alignment, and changes in density of the matrix and CNT nanoparticles. A higher resolution AFM scanner and Field Emission Scanning Electron Microscopy are necessary to observe nano-scale interphase mechanical properties and CNT orientation, respectively. Mode I interlaminar fracture testing demonstrated the effectiveness of CNT nanoparticles in preventing crack-jump and fiber-bridging effects. GIC for FCNT is 0.345±0.06 N-mm/mm2 at crack initiation, compared to 0.28±0.03 N-mm/mm2 for the plain epoxy reference sample. CNT nanoparticles increase the energy required for interlaminar fracture by promoting crack deflection and strengthening the interphase between CF and epoxy matrix through increased interfacial surface area.
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Stelescu, Maria Daniela, Mihai Georgescu, Maria Sonmez, Mihaela Nituica, and Adriana Stefan. "Elastomeric nanomaterials based on natural rubber for the food industry." In The 8th International Conference on Advanced Materials and Systems. INCDTP - Leather and Footwear Research Institute (ICPI), Bucharest, Romania, 2020. http://dx.doi.org/10.24264/icams-2020.iv.23.
Повний текст джерелаАнотація:
This paper presents the obtaining and characterization of new elastomeric nanocomposites based on natural rubber reinforced with plasticized starch, precipitated silica and layered clay, for obtaining consumer goods for the food industry. Obtaining nanocomposites was carried out by the technique of mixing and melt interleaving. The mixtures were vulcanized in the press, at high temperatures, using peroxides as vulcanizing agents, and triallyl cyanurate as vulcanizing coagent. In order to obtain products with improved characteristics, the influence of the amount of modified organic montmorillonite layered clay (OMMT) Nanomer I31PS and the adhesion promoter between mineral filler and polymer - bis-[3-(triethoxysilyl)-propyl]-tetrasulfane (TEPS) on the characteristics of the mixtures, was analysed. The rheological characteristics of the samples show an increase of the minimum torque at the increase in the amount of OMMT type nanofiller and a decrease in the optimal vulcanization time by adding the adhesion promoter between the rubber and the filler. An improvement of the mechanical characteristics of the samples was observed at the introduction of both OMMT and TEPS. These changes may be due to both the nanofiller reinforcement effect and the changes in the morphology of the mixture. The samples showed a good behaviour after immersion in different environments specific to the food industry (water, ethyl alcohol, 10% glucose solution, 0.9% sodium chloride solution and sunflower oil). SEM analyses indicate that the starch particles, together with the other ingredients of the mixture, are quasi uniform distributed in the elastomer matrix. Several superficial microcracks are observed, on the surface of the analysed material, without structural discontinuities or other defects.
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Maynard, Cole M., Julio A. Hernandez, Andrew Doak, Benjamin Mardikis, Monica Viz, Brittany Newell, Jose Garcia, and Tyler N. Tallman. "A Computational Study of Strain Sensing via 3D-Printed CNF-Modified PLA Strain Gauges." In ASME 2020 Conference on Smart Materials, Adaptive Structures and Intelligent Systems. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/smasis2020-2236.
Повний текст джерелаАнотація:
Abstract Additive manufacturing technologies and products have seen significant growth in the last decade but have the potential to see greater advancement with the addition of functional material properties in filaments, vastly expanding the product range. Polylactic acid (PLA) is a common fused deposition modeling (FDM) material used for additive manufacturing. Currently, filament materials are limited in terms of electrical properties with the majority of filaments being dielectric. Imparting electrical properties via nanofiller modification of traditionally insulating PLA is an exciting direction for multi-functional additive manufacturing. The work presented in this manuscript computationally explores the piezoresistive strain sensing performance of multi-functional PLA. Specifically, we use experimental conductivity data collected from carbon nanofiber (CNF)-modified PLA to calibrate a computational piezoresistivity model. This computational model is then used to simulate the resistance change-strain relationship of a representative additively manufactured sensor shape. This study shows that the CNF/PLA sensor exhibits a non-linear response with a strain-dependent gauge factor ranging from 15.0 in compression to up to approximately 33.2 in tension. Computational tools such as the ones presented herein are important for further development of additively manufactured sensors since it allows researchers to explore a wide design space (e.g. shape, material type, etc.) without resorting to trial and error experimentation. This allows the incredible versatility of additive manufacturing to be more thoroughly leveraged.
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Tiano, Thomas, Margaret Roylance, Benjamin Harrison, and Richard Czerw. "Intralaminar Reinforcement for Biomimetic Toughening of Bismaleimide Composites Using Nanostructured Materials." In ASME 2005 International Mechanical Engineering Congress and Exposition. ASMEDC, 2005. http://dx.doi.org/10.1115/imece2005-81689.
Повний текст джерелаАнотація:
Many conventional composite materials are composed of multiple layers of continuous fiber reinforced resin produced by lamination of b-staged prepreg and subsequent cure. These materials exhibit very high strength and stiffness in the plane, dominated by the properties of the fibers. The Achilles heel of such composites is the interlaminar strength, which is dependent on the strength of the unreinforced resin, often leading to failure by delamination under load. Current methods for increasing the interlaminar shear strength of composites consist of inserting translaminar reinforcement fibers through the entire thickness of a laminated composite, such as z-pin technology developed by Foster-Miller [1]. While effective, this technique adds several processing steps, including ultrasonic insertion of the z-pins into the laminate, subsequently causing a significant cost increase to laminated composites. Described in this paper is a process utilizing single-walled carbon nanotubes (SWNTs) and vapor grown carbon nanofibers as reinforcing elements promoting interlaminar shear strength and toughness in carbon fiber/bismaleimide (BMI) resin composites. The resulting composites mimic the natural reinforcing mechanism utilized in insect cuticles. Three different methods of increasing the affinity of these carbon nanofillers for the BMI matrix were explored. The mechanical properties of these composites were assessed using end notch flexure testing. The results indicated that including nanofiller at the laminae interface could increase the interlaminar shear strength of carbon fiber/BMI composites by up to 58%. SEM micrographs revealed that the nanofiller successfully bridged the laminae of the composite, thus biomimicking the insect cuticle. Composite fabrication techniques developed on this program would have a wide variety of applications in space and aerospace structures including leading and trailing edges of aircraft wings.