Tuning Thermal and Mechanical Properties of Polydimethylsiloxane with Carbon Fibers

In order to meet the needs of constantly advancing technologies, fabricating materials with improved properties and predictable behavior has become vital. To that end, we have prepared polydimethylsiloxane (PDMS) polymer samples filled with carbon nanofibers (CFs) at 0, 0.5, 1.0, 2.0, and 4.0 CF loadings (w/w) to investigate and optimize the amount of filler needed for fabrication with improved mechanical properties. Samples were prepared using easy, cost-efficient mechanical mixing to combine the PDMS and CF filler and were then characterized by chemical (FTIR), mechanical (hardness and tension), and physical (swelling, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and coefficient of thermal expansion) analyses to determine the material properties. We found that hardness and thermal stability increased predictably, while the ultimate strength and toughness both decreased. Repeated tension caused the CF-filled PDMS samples to lose significant toughness with increasing CF loadings. The hardness and thermal degradation temperature with 4 wt.% CF loading in PDMS increased more than 40% and 25 °C, respectively, compared with the pristine PDMS sample. Additionally, dilatometer measurements showed a 20% decrease in the coefficient of thermal expansion (CTE) with a small amount of CF filler in PDMS. In this study, we were able to show the mechanical and thermal properties of PDMS can be tuned with good confidence using CFs.

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Mechanical and Thermal Properties of R-High Density Polyethylene Composites Reinforced with Wheat Straw Particleboard Dust and Basalt Fiber

International Journal of Polymer Science ◽

10.1155/2018/5101937 ◽

2018 ◽

Vol 2018 ◽

pp. 1-10

Author(s):

Min Yu ◽

Haiyan Mao ◽

Runzhou Huang ◽

Zhenghao Ge ◽

Pujian Tian ◽

...

Keyword(s):

Mechanical Properties ◽

Thermal Expansion ◽

Wheat Straw ◽

High Density Polyethylene ◽

Coefficient Of Thermal Expansion ◽

Basalt Fiber ◽

High Density ◽

Mechanical And Thermal Properties ◽

Linear Coefficient ◽

Loading Level

The effect of individual and combined particleboard dust (PB dust) and basalt fibers (BFs) on mechanical and thermal expansion performance of the filled virgin and recycled high density polyethylene (HDPE) composites was studied. It was shown that the use of PB dust had a positive effect on improving mechanical properties and on reducing linear coefficient of thermal expansion (LCTE) values of filled composites, because the adhesive of the particle board held the wheat straw fibers into bundles, which made PB dust have a certain aspect ratio and high strength. Compared with the commonly used commercial WPC products, the flexural strength of PB dust/VHDPE, PB dust/RHDPE, and PB dust/VHDPE/RHDEPE at 40 wt% loading level increased by 79.9%, 41.5%, and 53.9%, respectively. When 40 wt% PB dust was added, the crystallization degree of the composites based on three matrixes decreased to 72.5%, 45.7%, and 64.1%, respectively. The use of PB dust can help lower the composite costs and increase its recyclability. Mechanical properties and LCTE values of composites with combined BF and PB dust fillers varied with PB dust and BF ratio at a given total filler loading level. As the BF portion of the PB dust/BF fillers increased, the LCTE values decreased markedly, which was suggested to be able to achieve a desirable dimensional stability for composites. The process provides a useful route to further recycling of agricultural wastes.

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Influence of Chopped Fibre Length on the Mechanical and Thermal Properties of Silk Fibre-Reinforced Poly(Butylene Succinate) Biocomposites

Polymers and Polymer Composites ◽

10.1177/096739110501300505 ◽

2005 ◽

Vol 13 (5) ◽

pp. 479-488 ◽

Cited By ~ 1

Author(s):

Sang Muk Lee ◽

Seong Ok Han ◽

Donghwan Cho ◽

Won Ho Park ◽

Seung Goo Lee

Keyword(s):

Mechanical Properties ◽

Thermal Expansion ◽

Thermal Properties ◽

Coefficient Of Thermal Expansion ◽

Fibre Length ◽

Present System ◽

Silk Fibre ◽

Mechanical And Thermal Properties ◽

Butylene Succinate ◽

Linear Coefficient

The influence of chopped fibre length on the mechanical and thermal properties of silk fibre ( Bombix mori) reinforced poly(butylene succinate) (PBS) biocomposites has been investigated in terms of tensile and flexural properties, thermal stability, thermal expansion, and dynamic mechanical properties. The chopped fibre lengths studied were 3.2 mm, 6.4 mm, 12.7 mm, and 25.4 mm. The results demonstrate that chopped silk fibres play an effective role in improving the mechanical properties of PBS in the present system. At a fixed fibre loading of 40 wt%, the tensile strength and modulus of the PBS control were improved by 69% and 228%, respectively, in comparison with those of the biocomposite reinforced with 25.4 mm silk fibres. The flexural strength and modulus of PBS were also greatly improved by 167% and 323%, respectively. The thermal properties of PBS resin increased when incorporating chopped silk fibres in the composite matrix. The biocomposites had much lower linear coefficient of thermal expansion (CTE) values and higher storage moduli than the PBS controls above the glass transition region, especially with reinforcing silk fibres of 25.4 mm long.

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Study of Mechanical Responses and Thermal Expansion of CNF-modified Polyester Nanocomposites Processed by Different Mixing Systems

MRS Proceedings ◽

10.1557/opl.2011.111 ◽

2011 ◽

Vol 1312 ◽

Author(s):

Muhammad E. Hossain ◽

Mohammad K. Hossain ◽

Mahesh Hosur ◽

Shaik Jeelani

Keyword(s):

Thermal Expansion ◽

Mechanical Response ◽

Carbon Nanofiber ◽

Coefficient Of Thermal Expansion ◽

Fracture Morphology ◽

Mechanical Analysis ◽

Mechanical And Thermal Properties ◽

Compression Tests ◽

Mechanical Mixing ◽

Static Compression

ABSTRACTIn this study, different dispersion techniques such as sonication at high frequency, mechanical mixing, and magnetic stirring methods were employed to infuse 0.1 to 0.4 wt.% carbon nanofiber (CNF) into polyester matrix to study the influence of CNF on mechanical and thermal properties of the polyester nanocomposites. Dispersion of CNF studied using scanning electron microscopy (SEM) micrographs revealed excellent dispersion of CNF using sonication when 0.2 wt.% CNF was mixed in polyester resulting in enhanced mechanical response. On the other hand, agglomerations were observed in samples prepared with other mixing methods. Polyester with 0.2 wt.% CNF samples prepared by sonication resulted in 88% and 16% increase in flexural strength and modulus, respectively, over neat samples. Quasi-static compression tests showed similar increasing trend with addition of 0.2 wt.% CNF. Dynamic mechanical analysis (DMA) showed 35% and 5 °C improvement in the storage modulus and glass transition temperature (Tg), respectively, in the 0.2 wt.% loaded samples. Thermal mechanical analysis (TMA) performed on neat and samples with 0.2 wt.% CNF showed lower coefficient of thermal expansion (CTE) in nanophased sample compared to neat. Fracture morphology evaluated using SEM revealed relatively rougher surface in CNF-loaded polyester compared to neat as a result of better interaction between fiber and matrix due to the presence of CNF.

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The Thermal Behavior of Lyocell Fibers Containing Bis(trimethylsilyl)acetylene

Polymers ◽

10.3390/polym13040537 ◽

2021 ◽

Vol 13 (4) ◽

pp. 537

Author(s):

Igor Makarov ◽

Markel Vinogradov ◽

Maria Mironova ◽

Georgy Shandryuk ◽

Yaroslav Golubev ◽

...

Keyword(s):

Thermal Expansion ◽

Thermal Behavior ◽

Carbon Fibers ◽

Coefficient Of Thermal Expansion ◽

Structural Features ◽

Amorphous Structure ◽

Processing Temperature ◽

Composite Fibers ◽

Scanning Calorimetry ◽

Lyocell Fibers

This study focuses on the preparation of carbon fiber precursors from solutions of cellulose in N-methylmorpholine-N-oxide with the addition of bis(trimethylsilyl)acetylene, studying their structural features and evaluating thermal behavior. The introduction of a silicon-containing additive into cellulose leads to an increase in the carbon yield during carbonization of composite precursors. The type of the observed peaks on the differential scanning calorimetry (DSC) curves cardinally changes from endo peaks intrinsic for cellulose fibers to the combination of endo and exo peaks for composite fibers. For the first time, coefficient of thermal expansion (CTE) values were obtained for Lyocell fibers and composite fibers with bis(trimethylsilyl)acetylene (BTMSA). The study of the dependence of linear dimensions of the heat treatment fibers on temperature made it possible to determine the relation between thermal expansion coefficients of carbonized fibers and thermogravimetric curves, as well as to reveal the relationship between fiber shrinkage and BTMSA bis(trimethylsilyl)acetylene content. Carbon fibers from composite precursors are obtained at a processing temperature of 1200 °C. A study of the structure of carbon fibers by X-ray diffraction, Raman spectroscopy, and transmission electron microscopy made it possible to determine the amorphous structure of the fibers obtained.

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Evaluation of CeSZ Thermal Barrier Coatings for Diesels

Thermal Spray 2000: Proceedings from the International Thermal Spray Conference ◽

10.31399/asm.cp.itsc2000p1179 ◽

2000 ◽

Author(s):

P.J. Huang ◽

J.J. Swab ◽

P.J. Patel ◽

W.S. Chu

Keyword(s):

Thermal Conductivity ◽

Thermal Expansion ◽

Thermal Barrier Coatings ◽

Coefficient Of Thermal Expansion ◽

Fuel Efficiency ◽

Atmospheric Plasma ◽

Thermal Barrier ◽

Mechanical And Thermal Properties ◽

Barrier Coatings ◽

Spray Process

Abstract The development of thermal barrier coatings (TBCs) for diesel engines has been driven by the potential improvements in engine power and fuel efficiency that TBCs represent. TBCs have been employed for many years to reduce corrosion of valves and pistons because of their high temperature durability and thermal insulative properties. There are research programs to improve TBCs wear resistance to allow for its use in tribologically intensive areas of the engine. This paper will present results from tribological tests of ceria stabilized zirconia (CeSZ). The CeSZ was applied by atmospheric plasma spray process. Various mechanical and thermal properties were measured including wear, coefficient of thermal expansion, thermal conductivity, and microhardness. The results show the potential use of CeSZ in wear sensitive applications in diesel applications. Keywords: Thermal Barrier Coating, Diesel Engine, Wear, Thermal Conductivity, and Thermal Expansion

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Effects of Steam Heat and Dry Heat Sterilization on Thermal and Mechanical Properties of Nylon and Policarbonate in Fabrication with Fused Filament

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.891.150 ◽

2021 ◽

Vol 891 ◽

pp. 150-163

Author(s):

Jorge Mauricio Fuentes ◽

Omar Flor Unda ◽

Santiago Ferrandiz ◽

Franyelit Suarez

Keyword(s):

Mechanical Properties ◽

Thermomechanical Analysis ◽

Mechanical Tests ◽

Effect Of Temperature ◽

Mechanical And Thermal Properties ◽

Scanning Calorimetry ◽

Thermal Tests ◽

Dry Heat ◽

Izod Impact ◽

Steam Heat

In this article presents evidence about performance of mechanical properties of polycarbonate and nylon materials, which are used in the additive manufacturing by deposition of molten material and that have been subjected to sterilization processes by moist heat at 121°C and dry heat at 140°C. This study provides useful information to consider the use of these materials in sanitary and sterile settings. Mechanical tests of tensile, flex, hardness, Izod impact, thermal tests in Differential Scanning Calorimetry DSC, Thermomechanical analysis TMA and Scanning Electron Microscopy SEM were performed. It is concluded that the mechanical and thermal properties have not been altered through the effect of temperature in sterilization processes.

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The influence of adding long basalt fiber on the mechanical and thermal properties of composites based on poly(oxymethylene)

Journal of Thermoplastic Composite Materials ◽

10.1177/0892705718806549 ◽

2018 ◽

Vol 33 (4) ◽

pp. 435-450 ◽

Cited By ~ 4

Author(s):

Patrycja Bazan ◽

Stanisław Kuciel ◽

Mariola Sądej

Keyword(s):

Mechanical Properties ◽

Thermal Properties ◽

Average Length ◽

Flexural Modulus ◽

Basalt Fiber ◽

Charpy Impact ◽

Mechanical And Thermal Properties ◽

Gravimetric Analysis ◽

Scanning Calorimetry ◽

Atr Spectroscopy

The work has evaluated the possibility of the potential reinforcing of poly(oxymethylene) (POM) by basalt fibers (BFs) and influence of BFs addition on thermal properties. Two types of composites were produced by injection molding. There were 20 and 40 wt% long BFs content with an average length of 1 mm. The samples were made without using a compatibilizer. In the experimental part, the basic mechanical properties (tensile strength, modulus of elasticity, strain at break, flexural modulus, flexural strength, and deflection at 3.5% strain) of composites based on POM were determined. Tensile properties were also evaluated at three temperatures −20°C, 20°C, and 80°C. The density and Charpy impact of the produced composites were also examined. The influence of water absorption on mechanical properties was investigated. Thermal properties were conducted by the differential scanning calorimetry, thermal gravimetric analysis, and fourier transform infrared (FTIR)-attenuation total reflection (ATR) spectroscopy analysis. In order to make reference to the effects of reinforcement and determine the structure characteristics, scanning electron microscopy images were taken. The addition of 20 and 40 wt% by weight of fibers increases the strength and the stiffness of such composites by more than 30–70% in the range scale of temperature. Manufactured composites show higher thermal and dimensional stability in relation to neat POM.

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Characterization of microwave-treated oil palm empty fruit bunch/glass fibre/polypropylene composites

Journal of Thermoplastic Composite Materials ◽

10.1177/0892705715614078 ◽

2015 ◽

Vol 30 (7) ◽

pp. 986-1002 ◽

Cited By ~ 6

Author(s):

MR Islam ◽

A Gupta ◽

M Rivai ◽

MDH Beg

Keyword(s):

Glass Fibre ◽

Oil Palm ◽

Melt Flow Index ◽

Flow Index ◽

Mechanical And Thermal Properties ◽

Empty Fruit Bunch ◽

Scanning Calorimetry ◽

Fixed Temperature ◽

Polypropylene Composites ◽

Degradation Temperature

Composites were prepared from recycled polypropylene (RPP), oil palm empty fruit bunch (EFB) and/or glass fibre (GF) using extrusion and injection moulding techniques. Two types of maleic anhydride-grafted polypropylene such as Polybond 3200 and Fusabond P 613 were used to improve the interfacial adhesion between fibres and matrix. The EFB: GF ratio was fixed as 70:30 and fibre loading was considered as 40 wt%. Microwave was used to treat the EFB fibre, which was soaked in a fixed mass concentration (12.5%) of alkali solution at different temperatures (70, 80 and 90°C) for a fixed period of time (60 min) and for different times (60, 90 and 120 min) at a fixed temperature (90°C). A magnetron controller was developed to control the time and temperature accurately for the treatment of fibre. Various characterization techniques such as density, melt flow index, tensile, Izod impact, flexural, field-emission scanning electron microscopy and water uptake testing were performed for the composites. Besides, thermogravimetric analysis and differential scanning calorimetry were also used to evaluate the thermal and crystalline properties of the composites, respectively. Result analyses revealed that microwave-treated fibre-based composites showed improved mechanical and thermal properties. EFB fibres treated at 90°C for 90 min were found to be suitable for better reinforcement into the composite in terms of mechanical, thermal and crystalline properties. Moreover, onset degradation temperature and water absorption properties were also found to be changed apparently due to treatment.

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Characteristics and mechanical properties changes due to incorporation of aloe vera in polyethylene-based film

Scientific Research Journal ◽

10.24191/srj.v17i2.9837 ◽

2020 ◽

Vol 17 (2) ◽

pp. 61

Author(s):

Siti Fatma Abd Karim ◽

Junaidah Binti Jai ◽

Ku Halim Ku Hamid ◽

Abdul Wafi Abdul Jalil

Keyword(s):

Mechanical Properties ◽

Thermal Degradation ◽

Aloe Vera ◽

Functional Materials ◽

Chain Structure ◽

Substantial Effect ◽

Scanning Calorimetry ◽

Degradation Temperature ◽

And Performance ◽

The Impact

Non-degradable properties of polyethylene (PE) films due to long-chain structure cause increment of solid waste plastic. Many researchers, with different purposes, have studied the incorporation of functional materials to PE. Studying the impact of incorporation of aloe vera (AV) into PE films in terms of its characteristic and mechanical properties is the main objective of this paper. The films were prepared using melt-blending and hot press technique. The characterization assessed for the PE and PE-AV films were spectroscopy, crystalline phase, thermal analysis and performance of mechanical properties of the sample. The functional group detected in spectroscopy studied did not show any changes for PE film or PE with the presence of AV. Lower thermal degradation temperature (Td) obtained for PE-AV3 while others film found no significant changes of Td value and only one peak of thermal degradation occurred for all film. The same goes to the analysis obtained from differential scanning calorimetry (DSC) data. However, the crystalline structure displayed momentous peak changes for PE with AV. The highest tensile strength (TS) obtained by PE-AV3, at once developing highest value of Young’s modulus (YM), modulus of resilience (UE) and modulus of toughness (UT). A certain amount of AV has substantial effect on changing the polymeric structure especially improving the mechanical properties of PE film. Therefore, AV has potential to become an additive for developing a new partially degradable PE film.

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