Experimental Investigation on Thermal Properties of Wood-Plastic Composites as Flat Panels

The aim of this research is investigating the thermal properties of wood-plastic composites (WPCs) in the form of flat panels. The study has included many properties such as: thermal conductivity, thermal stability, thermal expansion and melting point. The WPCs have made of high-density polyethylene (HDPE) and polypropylene (PP) incorporated with wood flour taken from pine trees. The studied concentrations of wood flour in the composites are (10, 20 or 30 %). The work was performed experimentally by manufacturing the specimens and measuring the thermal properties. The results show that the addition of 10% wood flour to the composite, leads to a reduction in the thermal conductivity of 4-10%, a reduction in thermal expansion of 8-12%, and an increase in the melting point of (2-3°C) for both HDPE and PP wood composites. It was found that wood could be used with plastics that have low melting points, such as: HDPE, LDPE, PP, PVDF and PA, to ensure high thermal stability.

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Thermal properties of sonicated graphene in coconut oil as a phase change material for energy storage in building applications1

International Journal of Low-Carbon Technologies ◽

10.1093/ijlct/ctaa018 ◽

2020 ◽

Vol 15 (4) ◽

pp. 629-636

Author(s):

Lulu Safira ◽

Nandy Putra ◽

Titin Trisnadewi ◽

Eny Kusrini ◽

Teuku Meurah Indra Mahlia

Keyword(s):

Thermal Conductivity ◽

Thermal Stability ◽

Thermal Properties ◽

Energy Storage ◽

Melting Point ◽

Phase Change ◽

Latent Heat ◽

Thermal Performance ◽

Coconut Oil ◽

Change Material

Abstract This study aims to investigate the thermal properties of a phase change material (PCM) based on coconut oil for building energy storage applications. Coconut oil is classified as an organic PCM composed of fatty acids made from renewable feedstock. However, low thermal conductivity is one of the major drawbacks of organic PCMs that must be improved. Graphene could be an effective material to enhance the thermal performance of organic PCMs. In this study, coconut oil with a latent heat capacity of 114.6 J/g and a melting point of 17.38°C was used. PCMs were prepared by sonicating graphene into coconut oil, as a supporting material. The mass fractions of the prepared PCMs were 0, 0.1, 0.2, 0.3, 0.4 and 0.5. Thermal conductivity tests were performed using a KD2 thermal property analyser under different ambient temperatures of 5, 10, 15, 20 and 25°C simulated with a circulating thermostatic bath. The latent heat, melting point and freezing point were determined through differential scanning calorimetry, the thermal stability was determined using thermogravimetric analysis (TGA) and the morphology and chemical structure were examined using transmission electron microscopy and Fourier-transform infrared spectroscopy, respectively. The results of this study showed that graphene addition to coconut oil improved the thermal performance, with the highest improvement seen in a 0.3 wt% sample at 20°C. The latent heat decreased by 11% owing to molecular movements within the PCM. However, TGA revealed that the composite PCMs showed good thermal stability in ambient building temperature ranges.

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Effects of filler type and content on the mechanical, morphological, and thermal properties of waste casting polyamide 6 (W-PA6G)-based wood plastic composites

BioResources ◽

10.15376/biores.16.1.655-668 ◽

2020 ◽

Vol 16 (1) ◽

pp. 655-668

Author(s):

Belgin Şeker Hirçin ◽

Hüseyin Yörür ◽

Fatih Mengeloğlu

Keyword(s):

Thermal Properties ◽

Wood Flour ◽

Crystalline Polymer ◽

Polyamide 6 ◽

Polymeric Matrix ◽

Melt Temperature ◽

Wood Plastic Composites ◽

Plastic Composites ◽

Lignocellulosic Filler ◽

Butyl Benzene

Cast polyamide 6 (PA6G), trade name Castamide, is a semi-crystalline polymer widely used in the engineering plastics industry. There is a need to recycle valuable waste (W)-PA6G generated during part manufacturing of this polymer (approximately 30%). This study attempts to utilize W-PA6G in the manufacture of wood-plastic composites as a polymeric matrix. The effect of lignocellulosic filler type (FT) and filler content (FC) on the mechanical, morphological, and thermal properties of W-PA6G-based composites were investigated. During manufacturing, N-butyl benzene sulfonamide (N-BBSA) and lithium chloride (LiCl) were utilized as a plasticizer and a melt temperature-lowering salt, respectively. The rice husk (RH) and Uludağ fir wood flour (WF) filled W-PA6G-based composites were successfully manufactured using a combination of extrusion and injection molding. Compared to RH filled composites, WF filled composites provided better tensile and flexural properties (both strength and modulus) at 20% and 30% filler contents. Morphological study showed the nonhomogeneous distribution of fillers in the polymeric matrix. Lignocellulosic filler resulted in reduced melting temperature and crystallinity of W-PA6G-based composites. This reduction was more pronounced in RH filled composites.

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Effects of PMDI Treatments on Thermal Properties of Silvergrass Reinforced High Density Polyethylene Composites

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.423-426.84 ◽

2013 ◽

Vol 423-426 ◽

pp. 84-88

Author(s):

Dong Xue ◽

Wang Wang Yu ◽

Qin Liu ◽

Lu Jing ◽

Xue Jing Liu ◽

...

Keyword(s):

Thermal Stability ◽

Thermal Properties ◽

High Density Polyethylene ◽

Nucleating Agent ◽

High Density ◽

Wood Plastic Composites ◽

Plastic Composites ◽

Methylene Diphenyl Diisocyanate ◽

Thermal Stability Of ◽

Polyethylene Composites

In this study, silvergrass (SV) reinforced high density polyethylene (HDPE) composites were prepared. The effects of polymeric methylene diphenyl diisocyanate (PMDI), slivergrass fibers (SV) content on the thermal, crystalline properties of wood plastic composites (WPCs) were investigated. It was found that Compared with the untreated WPCs, the thermal stability of the composites after incorporation of PMDI treated SV fibers was significantly improved. Moreover, the results show that with PMDI treated composites, SV was an effective heterogeneous nucleating agent.

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Design, Preparation and Thermal Properties of (La0.4Sm0.5Yb0.1)2Zr2O7 Ceramic for Thermal Barrier Coatings

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.512-515.469 ◽

2012 ◽

Vol 512-515 ◽

pp. 469-473 ◽

Cited By ~ 1

Author(s):

L. Liu ◽

Z. Ma ◽

F.C. Wang ◽

Q. Xu

Keyword(s):

Thermal Conductivity ◽

Thermal Expansion ◽

Thermal Properties ◽

Rare Earth ◽

Thermal Expansion Coefficient ◽

Thermal Barrier Coatings ◽

Expansion Coefficient ◽

Phonon Transport ◽

Thermal Barrier ◽

Barrier Coatings

According to the theory of phonon transport and thermal expansion, a new complex rare-earth zirconate ceramic (La0.4Sm0.5Yb0.1)2Zr2O7, with low thermal conductivity and high thermal expansion coefficient, has been designed by doping proper ions at A sites. The complex rare-earth zirconate (La0.4Sm0.5Yb0.1)2Zr2O7 powder for thermal barrier coatings (TBCs) was synthesized by coprecipitation-calcination method. The phase, microstructure and thermal properties of the new material were investigated. The results revealed that single phase (La0.4Sm0.5Yb0.1)2Zr2O7 with pyrochlore structure was synthesized. The thermal conductivity and the thermal expansion coefficient of the designed complex rare-earth zirconate ceramic is about 1.3W/m•K and 10.5×10-6/K, respectively. These results imply that (La0.4Sm0.5Yb0.1)2Zr2O7 can be explored as the candidate material for the ceramic layer in TBCs system.

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Thermal Properties of Yttrium Aluminum Garnett From Molecular Dynamics Simulations

ASME/JSME 2011 8th Thermal Engineering Joint Conference ◽

10.1115/ajtec2011-44343 ◽

2011 ◽

Cited By ~ 1

Author(s):

Majid S. al-Dosari ◽

D. G. Walker

Keyword(s):

Thermal Conductivity ◽

Molecular Dynamics ◽

Thermal Expansion ◽

Thermal Properties ◽

Specific Heat ◽

Molecular Dynamics Simulations ◽

Yttrium Aluminum Garnet ◽

System Size ◽

Yttrium Aluminum ◽

Dynamics Simulations

Yttrium Aluminum Garnet (YAG, Y3Al5O12) and its varieties have applications in thermographic phosphors, lasing mediums, and thermal barriers. In this work, thermal properties of crystalline YAG where aluminum atoms are substituted with gallium atoms (Y3(Al1−xGax)5O12) are explored with molecular dynamics simulations. For YAG at 300K, the simulations gave values close to experimental values for constant-pressure specific heat, thermal expansion, and bulk thermal conductivity. For various values of x, the simulations predicted no change in thermal expansion, an increase in specific heat, and a decrease in thermal conductivity for x = 50%. Furthermore, the simulations predicted a decrease in thermal conductivity with decreasing system size.

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Primary pyroelectric transition temperatures of binary nitrides (AlN, GaN and InN)

Modern Physics Letters B ◽

10.1142/s0217984919500490 ◽

2019 ◽

Vol 33 (05) ◽

pp. 1950049

Author(s):

Muralidhar Swain ◽

Sushant K. Sahoo ◽

Bijay K. Sahoo

Keyword(s):

Thermal Conductivity ◽

Thermal Expansion ◽

Thermal Properties ◽

Transition Temperature ◽

Negative Thermal Expansion ◽

Polarization Field ◽

Piezoelectric Polarization ◽

Polarization Mechanism ◽

Prior Literature

The primary pyroelectric transition temperature of wurtzite nitrides (AlN, GaN and InN) has been explored theoretically from their thermal properties. The spontaneous and piezoelectric polarization modifies the thermal conductivity of nitrides. The thermal conductivity [Formula: see text] as a function of temperature including and excluding the polarization mechanism predicts a transition temperature [Formula: see text] between primary and secondary pyroelectric effects. Below [Formula: see text], thermal conductivity including polarization field [Formula: see text] is lesser than thermal conductivity excluding polarization field [Formula: see text]. This is due to negative thermal expansion in binary nitrides below [Formula: see text]; however, above [Formula: see text], [Formula: see text]. [Formula: see text] is significantly contributed by piezoelectric polarization above [Formula: see text] due to thermal expansion which is the reason for the secondary pyroelectric effect. The transition temperature [Formula: see text] for AlN, GaN and InN has been predicted as 100 K, 70 K and 60 K, respectively, which fit well with the prior literature studies. This report proposes that thermal properties’ study can reveal the role of acoustic phonons in pyroelectricity.

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In situ fabrication of wood flour/nano silica hybrid and its application in polypropylene‐based wood‐plastic composites

Polymer Composites ◽

10.1002/pc.25389 ◽

2019 ◽

Vol 41 (2) ◽

pp. 573-584 ◽

Cited By ~ 2

Author(s):

Yuanbin Ma ◽

Hui He ◽

Bai Huang ◽

Huaishuai Jing ◽

Zijin Zhao

Keyword(s):

Wood Flour ◽

Nano Silica ◽

Wood Plastic Composites ◽

In Situ Fabrication ◽

Plastic Composites ◽

Silica Hybrid

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Thermal properties of kinetic spray Al–SiC metal-matrix composite

Journal of Materials Research ◽

10.1557/jmr.2003.0117 ◽

2003 ◽

Vol 18 (4) ◽

pp. 855-860 ◽

Cited By ~ 25

Author(s):

Gary L. Eesley ◽

Alaa Elmoursi ◽

Nilesh Patel

Keyword(s):

Thermal Conductivity ◽

Thermal Expansion ◽

Thermal Properties ◽

Metal Matrix ◽

Volume Fraction ◽

Spray Deposition ◽

Deposition Process ◽

Matrix Composites ◽

Kinetic Spray ◽

Compositional Variations

Kinetic spray deposition provides a new means for producing composite materials with tailored physical properties. We report on measurements of the thermal conductivity and thermal-expansion coefficient for several compositional variations of kinetically sprayed Al–SiC metal-matrix composites. As a result of the deposition process, inclusion of SiC particles saturates in the 30–40% volume fraction range.

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