Effect of chemical treatment on thermal properties of hair fiber-based reinforcement of HF/HDPE composites

Abstract The present study deals with the effects of fiber loading and alkali treatment (AT) on thermal behavior of a hair fiber (HF)-reinforced high-density polyethylene (HDPE) composite. The HF/HDPE-reinforced polymer composite has been prepared through a compression molding technique, which provided optimum thermal stability at 15 wt% of the fiber in the reinforced composite. The thermal stability of the composite has been investigated using a thermal analyzer [thermogravimetric analysis (TGA), derivative thermogravimetric analysis (DTG) and differential scanning calorimetry (DSC)]. The ATs of HF-reinforced composites have affected the thermal stability of the material, in which the observed optimum thermal stability is 0.25 N AT 15% HF/HDPE-reinforced composites. Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM) and tensile test played an important role in the study of the thermal stability of the material. FTIR analysis was used to investigate the chemical groups between the fiber and matrix. The morphology of the fiber is beneficial for the study of the surface treatment effect on the HF. The tensile test examined the optimum strength at 0.25 N AT 15% HF/HDPE composite, and a good relationship between the thermal and mechanical properties was also observed.

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Thermal Stability of N-Heterocycle-Stabilized Iodanes – A Systematic Investigation

10.26434/chemrxiv.8964848 ◽

2019 ◽

Author(s):

Andreas Boelke ◽

Yulia A. Vlasenko ◽

Mekhman S. Yusubov ◽

Boris Nachtsheim ◽

Pavel Postnikov

Keyword(s):

Thermal Stability ◽

Differential Scanning Calorimetry ◽

Thermogravimetric Analysis ◽

Systematic Investigation ◽

Scanning Calorimetry ◽

Thermal Stability Of

The thermal stability of pseudocyclic and cyclic N-heterocycle-stabilized (hydroxy)aryl- and mesityl(aryl)-l3-iodanes (NHIs) through thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) is investigated. NHIs bearing N-heterocycles with a high N/C-ratio such as triazoles show among the lowest descomposition temperatures and the highest decomposition energies. A comparison of NHIs with known (pseudo)cyclic benziodoxolones is made and we further correlated their thermal stability with reactivity in a model oxygenation.

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Synthesis and Thermal Stability of Unsaturated Polyamides

High Performance Polymers ◽

10.1088/0954-0083/4/2/001 ◽

1992 ◽

Vol 4 (2) ◽

pp. 67-71

Author(s):

N. R. Patel ◽

N. Z. Patel ◽

R. M. Patel

Keyword(s):

Thermal Stability ◽

Differential Scanning Calorimetry ◽

Thermogravimetric Analysis ◽

Scanning Calorimetry ◽

Aromatic Diamines ◽

Good Thermal Stability ◽

Kinetics Of Decomposition ◽

Glutaconic Acid ◽

Kinetics Of ◽

Thermal Stability Of

Unsaturated polyamides were prepared by condensing /3(4-ethoxyphenyl) glutaconic acid with various aromatic diamines. The polycondensates were characterized by IR spectroscopy, vapor phase osmometry, thermogravimetric analysis, differential scanning calorimetry and elemental analysis. All resins were found to decompose in the range '-210-600 °C. The kinetics of decomposition were studied. The results indicated that the resins possess reasonably good thermal stability.

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Thermal stability of N-heterocycle-stabilized iodanes – a systematic investigation

Beilstein Journal of Organic Chemistry ◽

10.3762/bjoc.15.223 ◽

2019 ◽

Vol 15 ◽

pp. 2311-2318 ◽

Cited By ~ 9

Author(s):

Andreas Boelke ◽

Yulia A Vlasenko ◽

Mekhman S Yusubov ◽

Boris J Nachtsheim ◽

Pavel S Postnikov

Keyword(s):

Thermal Stability ◽

Differential Scanning Calorimetry ◽

Thermogravimetric Analysis ◽

Systematic Investigation ◽

Scanning Calorimetry ◽

Wide Range ◽

C Decomposition ◽

Thermal Stability Of ◽

Peak Decomposition

The thermal stability of pseudocyclic and cyclic N-heterocycle-stabilized (hydroxy)aryl- and mesityl(aryl)-λ3-iodanes (NHIs) through thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) is investigated. Peak decomposition temperatures (T peak) were observed within a wide range between 120 and 270 °C. Decomposition enthalpies (ΔH dec) varied from −29.81 to 141.13 kJ/mol. A direct comparison between pseudocyclic and cyclic NHIs revealed high T peak but also higher ΔH dec values for the latter ones. NHIs bearing N-heterocycles with a high N/C-ratio such as triazoles show among the lowest T peak and the highest ΔH dec values. A comparison of NHIs with known (pseudo)cyclic benziodoxolones is made and we further correlated their thermal stability with reactivity in a model oxygenation.

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Characterization of Date Palm Fiber-Reinforced Different Polypropylene Matrices

Polymers ◽

10.3390/polym12030597 ◽

2020 ◽

Vol 12 (3) ◽

pp. 597 ◽

Cited By ~ 5

Author(s):

Mohammed Sh. Al-Otaibi ◽

Othman Y. Alothman ◽

Maher M. Alrashed ◽

Arfat Anis ◽

Jesuarockiam Naveen ◽

...

Keyword(s):

Thermal Stability ◽

Date Palm ◽

Alkali Treatment ◽

Fiber Reinforced ◽

Scanning Calorimetry ◽

Palm Fiber ◽

Pull Out ◽

Hemicellulose Removal ◽

The Matrix ◽

Thermal Stability Of

In this study, the effect of different polypropylene (PP) matrices (homopolymer (HPP), impact copolymer (ICP), and recycled polypropylene (rPP)) on the mechanical, morphological, and thermal properties of date palm fiber (DPF)-reinforced PP composites was investigated. The DPFs were treated with an alkali solution, and composites were fabricated with different DPF loadings (5, 10, and 15 wt %) and lengths (less than 2 mm and 8–12 mm). It was found that the tensile properties of the DPF/ICP and DPF/rPP composites were similar to those of the DPF/HPP composites. The addition of fiber to the matrix reduced its tensile strength but increased the modulus. The alkali treatment improved the compatibility between the fibers and the matrix by removing hemicellulose and other impurities. Fourier transform infrared spectroscopy confirmed hemicellulose removal. The morphology of the alkali-treated fractured tensile specimen revealed improved adhesion and less fiber pull out. Differential scanning calorimetry revealed that the alkali treatment enhanced the crystallinity index. Thermogravimetric analysis showed that the addition of DPFs into the PP matrix reduced the thermal stability of the composite. However, the thermal stability of the treated fiber-reinforced rPP and ICP composites was similar to that of the DPF/HPP composite. Hence, rPP can be used as an alternative to HPP with DPFs.

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The Influence of Environmentally Friendly Flame Retardants on the Thermal Stability of Phase Change Polyurethane Foams

Materials ◽

10.3390/ma13030520 ◽

2020 ◽

Vol 13 (3) ◽

pp. 520 ◽

Cited By ~ 2

Author(s):

Dong Liu ◽

Anjie Hu

Keyword(s):

Thermal Stability ◽

Thermogravimetric Analysis ◽

Phase Change ◽

Thermal Insulation ◽

Polyurethane Foams ◽

Infrared Spectrometry ◽

Expandable Graphite ◽

Insulation Material ◽

Scanning Calorimetry ◽

Thermal Stability Of

To improve thermal insulation, microencapsulated phase change materials (micro-PCMs), expandable graphite (EG), and ammonium polyphosphate (APP) were introduced into polyurethane foam (PUF) to enhance the thermal stability and improve the thermal insulation behavior. The morphology of the PUF and micro-PCM was studied using a scanning electronic microscope (SEM), while the thermophysical properties of the PUF were investigated using a hot disk thermal constants analyzer and differential scanning calorimetry (DSC). The thermal stability of the PUF was investigated by thermogravimetric analysis (TGA), and the gas products volatilized from the PUF were analyzed by thermogravimetric analysis coupled with Fourier transform infrared spectrometry (TGA-FTIR). The results revealed that the thermal conductivities of the PUF were reduced because micro-PCM is effective in absorbing energy, showing that the PUF functions not only as a thermal insulation material but also as a heat sink for energy absorption. Moreover, the EG and APP were found to be effective in improving the thermal stabilities of the PUF, and the optimized formulation among EG, APP, and micro-PCMs in the PUF showed a significant synergistic effect.

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Glass Fiber Reinforced Composites of Coloured Epoxy Resin Cured with Different Amines

Polymers and Polymer Composites ◽

10.1177/096739110201000604 ◽

2002 ◽

Vol 10 (6) ◽

pp. 441-446

Author(s):

Milan R. Patel ◽

Manish P. Patel ◽

Rashmika H. Patel ◽

Ranjan G. Patel

Keyword(s):

Thermal Stability ◽

Epoxy Resin ◽

Chemical Resistance ◽

The Novel ◽

Reinforced Composites ◽

Scanning Calorimetry ◽

Good Thermal Stability ◽

Glass Fiber Reinforced ◽

Fibre Composites ◽

Thermal Stability Of

A novel coloured epoxy resin has been synthesized by reaction between epichlorohydrin and bisazodiol. The curing of the resin, blended with a DGEBA resin, were characterized by differential scanning calorimetry (DSC). The thermal stability of the cured products has been investigated by thermogravimetric analysis (TGA). The cured products showed good thermal stability. Glass fibre composites were fabricated by blending a DGEBA resin and the novel coloured epoxy resin and their mechanical properties, electrical properties and chemical resistance were studied.

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Studies on a Miscible Polyimide Blend

High Performance Polymers ◽

10.1088/0954-0083/9/3/006 ◽

1997 ◽

Vol 9 (3) ◽

pp. 263-279 ◽

Cited By ~ 17

Author(s):

J A Campbell ◽

A A Goodwin ◽

F W Mercer ◽

V Reddy

Keyword(s):

Thermal Stability ◽

Differential Scanning Calorimetry ◽

Thermogravimetric Analysis ◽

Physical Aging ◽

Adhesive Bond ◽

Mechanical Analysis ◽

Scanning Calorimetry ◽

Adhesive Properties ◽

Dynamic Mechanical ◽

Thermal Stability Of

Blends of polyimides XU-218 and PEI were investigated using differential scanning calorimetry, dynamic mechanical analysis, thermogravimetric analysis and adhesive bond testing. The thermal stability of the blends increased as the proportion of PEI increased while the α-relaxation of the blends occurred at a slower rate and was broader and more cooperative in some blends, compared with the pure polymers. Physical aging of the pure polymers and blends in the glass state revealed changes in relaxation rate and lost enthalpy that were also consistent with blends not behaving as simple mixtures. The dynamic mechanical and physical aging behaviour was attributed to an increase in density on blending which decreased the unoccupied volume and increased the constraints on molecular mobility, as well as to the presence of concentration fluctuations. The adhesive properties of the blends were also investigated and bond strength was found to vary with blend composition and test temperature.

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Effect of alkali treatment on the thermal properties of wheat straw fiber reinforced epoxy composites

Journal of Composite Materials ◽

10.1177/0021998316646168 ◽

2016 ◽

Vol 51 (3) ◽

pp. 323-331 ◽

Cited By ~ 6

Author(s):

Varun Mittal ◽

Shishir Sinha

Keyword(s):

Thermal Stability ◽

Thermal Properties ◽

Wheat Straw ◽

Fiber Composite ◽

Alkali Treatment ◽

Epoxy Composites ◽

Scanning Calorimetry ◽

Ftir Studies ◽

Four Levels ◽

Thermal Stability Of

This paper focuses on the study of the effect of fiber content and alkali treatment on the thermal properties of wheat straw epoxy composite. Four levels of fiber loading (10, 20, 30, and 40 wt%) of wheat straw and three levels of alkali treatment (1, 3, and 5%) were considered and merged into epoxy composites. The composites were prepared by hand layup technique. The thermal stability of the components was studied by thermogravimetric analysis and differential scanning calorimetry, as well as by the differential thermogravimetric. The experimental results show that the thermal stability of the composites prepared from 3% alkali-treated fibers is superior as compared to the untreated and another level of alkali-treated fiber composite. This is mainly due to the efficient fiber–matrix adhesion in the alkali-treated wheat straw epoxy composites. Scanning Electron Microscopy (SEM) and Fourier Transform Infrared Spectroscopy (FTIR) studies were carried out to evaluate the microstructure and composition of wheat straw fiber/epoxy composites, respectively.

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