Effect of polyethylene glycol on mechanical properties of bamboo fiber-reinforced polylactic acid composites

The bamboo fiber (BF)-reinforced polylactic acid (PLA) composites were prepared using the twin-screw extruder and injection molding. Thermal gravimetric analyzer results indicated the thermal stability of BF/PLA composites decreased with increasing BF content. Differential scanning calorimeter and X-ray diffraction curves showed that BF played a role as a nucleating agent, but the crystallinity of composite materials decreased with the increasing BF content. The melt flow rate of composites reduced with the increase in BF content, resulting in a poorer processing property. The processability of the composites was improved with the addition of high molecular polyethylene glycol (PEG). Mechanics performance test showed that tensile strength and bending strength of composites increased at low loading with the BF content increased then decreased when the loading continued to increase. The tensile strength of the composite materials reached 65.46 MPa when alkali-treated BF (ABF) content was 20 wt %. The flexural strength of the composites reached 97.94 MPa when ABF content was 10 wt %. Impact performance has also been improved. PEG-20000 was the best plasticizer among the PEG-6000,PEG-10000, and PEG-20000. When the component of PEG was 10 wt %, the elongation increased by 56%. The scanning electron microscopy (SEM) result showed that the fracture of the composites was smooth, most ABF were wrapped in matrix and distribution of ABF in PLA matrix was more uniform. It means that interfacial compatibility of bamboo fiber and PLA improved after BF modified by alkali. High molecular weight PEG enhance melt flow ability of polymer, result in fibers were further enclosed in the PLA matrix and increase properties of composites. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47709.     

Synergistic effects of polyethylene glycol and organic montmorillonite on the plasticization and enhancement of poly(lactic acid)

Poly(lactic acid) (PLA)/polyethylene glycol (PEG)/organic montmorillonite (OMMT) composites were prepared by melt blending, and their mechanical, rheological behavior, crystalline behavior, and thermal stability were investigated. Results showed that the elongation-at-break and notch-impact strength of PLA/15PEG/1.5OMMT were 466.45% and 4.34 kJ m⁻², respectively, which were nearly 42 and 2 times higher than those of PLA, respectively. The elongation-at-break of PLA/15PEG/1.5OMMT was also 33 times higher than that of PLA/15PEG and 30 times that of PLA/1.5OMMT. With addition of PEG, PLA chains could insert to OMMT effectively and increase the layer space of OMMT. The characteristics of dynamic behavior and fracture morphology showed that the plasticizer PEG could soften the PLA matrix, leading to easy plastic deformation. OMMT was well distributed in the PLA matrix and able to transfer the stress of external forces, thereby contributing to the matrix yielding initiation and expansion of polymer composites. The synergistic effect of OMMT and PEG was determined by studying the mechanical properties of PLA/PEG/OMMT composite. Differential scanning calorimetry and thermogravimetry studies revealed that OMMT as a nucleating agent improved crystallization and thermal stability. Thus, the synergistic effect of OMMT and PEG balanced the stiffness and toughness of PLA. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47576.     

Properties and Degradation of Novel Fully Biodegradable PLA/PHB Blends Filled with Keratin

The utilization of keratin waste in new materials formulations can prevent its environmental disposal problem. Here, novel composites based on biodegradable blends consisting of poly(lactic acid) (PLA) and poly(3-hydroxybutyrate) (PHB), and filled with hydrolyzed keratin with loading from 1 to 20 wt % were prepared and their properties were investigated. Mechanical and viscoelastic properties were characterized by tensile test, dynamic mechanical thermal analysis (DMTA) and rheology measurements. The addition of acetyltributyl citrate (ATBC) significantly affected the mechanical properties of the materials. It was found that the filled PLA/PHB/ATBC composite at the highest keratin loading exhibited similar shear moduli compared to the un-plasticized blend as a result of the much stronger interactions between the keratin and polymer matrix compared to composites with lower keratin content. The differences in dynamic moduli for PLA/PHB/ATBC blend filled with keratin depended extensively on the keratin content while loss the factor values progressively decreased with keratin loading. Softening interactions between the keratin and polymer matrix resulted in lower glass transitions temperature and reduced polymer chain mobility. The addition of keratin did not affect the extent of degradation of the PLA/PHB blend during melt blending. Fast hydrolysis at 60 °C was observed for composites with all keratin loadings. The developed keratin-based composites possess properties comparable to commonly used thermoplastics applicable for example as packaging materials.     

Poly(lactic acid) composite films reinforced with microcrystalline cellulose and keratin from chicken feather fiber in 1-butyl-3-methylimidazolium chloride

Amphiphilic keratin from chicken feather fiber (CFF) and hydrophilic cellulose were incorporated as fillers into hydrophobic poly(lactic acid) (PLA) polymer blend. This study implemented ionic liquid (IL) of 1-butyl-3-methylimidazolium chloride (BMIMCl) to dissolve the 1 wt % fillers. The composite films were compared with and without the addition of IL prepared from five sets of ratios of CFF to MCC using measuring mixers and compression molding. Thermal analysis showed that increase in CFF composition decreases the glass-transition temperature (T _g), and crystallization temperature (T _c) as well as increases the degree of crystallinity. PLA composite with the 70/30 ratio of CFF to MCC was found to be the optimum composition in obtaining considerably low T _g and high crystallinity. BMIMCl enhanced the miscibility of the composites as observed in scanning electron microscope images and single T _g. Apart from creating porous structure and lowering mechanical hardness, BMIMCl also decreased the thermal stability of the PLA composites. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47642.     

Preparation,characterization, and biodegradability of renewable resource‐based composites from recycled polylactide bioplastic and sisal fibers

The biodegradability, morphology, and mechanical thermal properties of composite materials composed of polylactide (PLA) and sisal fibers (SFs) were evaluated. Composites containing acrylic acid‐grafted PLA (PLA‐g‐AA/SF) exhibited noticeably superior mechanical properties because of greater compatibility between the two components. The dispersion of SF in the PLA‐g‐AA matrix was highly homogeneous as a result of ester formation and the consequent creation of branched and crosslinked macromolecules between the carboxyl groups of PLA‐g‐AA and hydroxyl groups in SF. Furthermore, with a lower melt temperature, the PLA‐g‐AA/SF composite is more readily processed than PLA/SF. Both composites were buried in soil to assess biodegradability. Both the PLA and the PLA‐g‐AA/SF composite films were eventually completely degraded, and severe disruption of film structure was observed after 6–10 weeks of incubation. Although the degree of weight loss after burial indicated that both materials were biodegradable even with high levels of SF, the higher water resistance of PLA‐g‐AA/SF films indicates that they were more biodegradable than those made of PLA. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Evaluation of the removal of n-butanol vapor by the poly(lactic acid)-zeolite-TiO2 composite and formation of by-products

The use of polymeric films incorporated with zeolite-TiO₂ composites associated with UV radiation can be an alternative in the removal of volatile organic compounds (VOCs) through the adsorption and photodegradation processes. This study produced poly(lactic acid) (PLA) films incorporated with 13× zeolite, TiO₂, and 13×-TiO₂ zeolite composite to remove n-butanol and evaluate the by-products generated in the process. The results showed that 13× zeolite and TiO₂ added individually or as a composite to PLA, gave the polymer matrix a significant increase in the removal capacity of n-butanol. The best performance was presented by the zeolite-TiO₂, composite, confirming a synergistic effect. However, the formation of CO and CO₂ exceeded the expected values, with the verification that the polymeric matrix underwent photodegradation action by TiO₂. The polymeric film only containing zeolite is the most suitable for the removal of VOCs, as it did not present degradation of the PLA, generating a lower concentration of by-products.     

In situ fibre‐reinforced composite films of poly(lactic acid)/low‐density polyethylene blends: effects of composition on morphology,transport and mechanical properties

This study aimed to investigate the effects of blend composition on packaging‐related properties of poly(lactic acid) (PLA) and low density polyethylene (LDPE) blown films. Blend films with PLA contents of 5–20 wt% were produced and compared. Scanning electron micrographs of cross‐sectional cryofractured surfaces of the blend films revealed that in situ fibre‐reinforced composites were obtained. Viscosity ratio of the polymer components of ca 1 confirmed that fibre formation was favourable for this blend system. PLA microdomains were dispersed throughout the film in forms of long fibres (length‐to‐diameter ratio > 100) and ribbons. The number of fibres and ribbons increased with an increase of PLA content. Critical content of PLA was found to be 20 wt% for effective improvement of both moduli and gas barrier properties. Incorporation of poly[ethylene‐co‐(methyl acrylate)] compatibilizer showed minimal effect on PLA structure. However, it did improve moduli and O₂ barrier properties when sufficient amount (1.5 pph) was used in 10 wt% PLA/LDPE. In short, flow behaviour, ratio of polymer components and degree of compatibility together played intricate roles in the morphology and hence mechanical and transport properties of PLA/LDPE immiscible blends. © 2017 Society of Chemical Industry     

Thermal and mechanical properties of plasticized poly(L‐lactic acid)

Acetyl tri‐n‐butyl citrate (ATBC) and poly(ethyleneglycol)s (PEGs) with different molecular weights (from 400 to 10000) were used in this study to plasticize poly(L‐lactic acid) (PLA). The thermal and mechanical properties of the plasticized polymer are reported. Both ATBC and PEG are effective in lowering the glass transition (T_g) of PLA up to a given concentration, where the plasticizer reaches its solubility limit in the polymer (50 wt % in the case of ATBC; 15–30 wt %, depending on molecular weight, in the case of PEG). The range of applicability of PEGs as PLA plasticizers is given in terms of PEG molecular weight and concentration. The mechanical properties of plasticized PLA change with increasing plasticizer concentration. In all PLA/plasticizer systems investigated, when the blend T_g approaches room temperature, a stepwise change in the mechanical properties of the system is observed. The elongation at break drastically increases, whereas tensile strength and modulus decrease. This behavior occurs at a plasticizer concentration that depends on the T_g‐depressing efficiency of the plasticizer. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 1731–1738, 2003     

Mechanical,barrier, and thermal properties of poly(lactic acid)/poly(trimethylene carbonate)/talc composite films

Poly(l ‐lactic acid) (PLA) is now a very attractive polymer for food packaging applications. In this study, PLA/poly(trimethylene carbonate) (PTMC)/talc composite films were prepared by solvent casting. The influence of the talc loading (0, 1, 2, and 3 wt %) on the phase morphology of the PLA/PTMC/talc composites and the improvement in the resulting properties are reported in this article. The scanning electron microscopy images of the composite films demonstrated good compatibility between the PLA and PTMC, whereas talc was not thoroughly distributed in the PLA matrix at talc contents exceeding 3 wt %. The tensile strength and elongation at break of the composite films significantly improved (p < 0.05). On the contrary, the water vapor permeability and oxygen properties of the composite films decreased by 24.7 and 39.2%, respectively, at the 2 wt % talc loading. Differential scanning calorimetry showed that the crystallinity of the PLA phase increased with the presence of talc filler in the PLA/PTMC/talc composites. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2014 , 131, 40016.     

The relationships between mixing and properties of filled polymers and foams

The increased utilization of reinforced polymeric blend composite materials has prompted renewed interest in mathematical models which can explain or predict the characteristics of processing and the properties of composite materials in terms of the properties and concentration of the components. As a first step toward developing the rules for multicomponent systems we restrict our attention to the Lee-Nielsen's model and concepts of two-component systems with particulate inclusions embedded in a continuous matrix. The following property-mixing relationships are then discussed: (1) reinforcement of uncured and cured rubber composites; (2) thermal expansion of polymer composites; (3) elastic modulus, and thermal conductivity of (reinforced) polymeric foam materials; and (4) heat buildup of rubber composites. Some important concepts and principles which have evolved from our experimental attempts at correlating the behavior of heterogeneous multiphase polymer materials are also discussed.     

Thermo‐rheological and interfacial properties of polylactic acid/polyethylene glycol blends toward the melt electrospinning ability

The electrospinning ability of PLA/PEG system at the melt state was investigated through the viscoelastic parameters obtained from dynamic shear and extensional rheometers. PLA and PEG were melt‐blended at various composition ratios. Effect of PEG concentration on the PLA thermal behavior was studied by the differential scanning calorimetry (DSC). According to DSC and wide‐angle X‐ray diffraction, the PLA crystallinity increased and the crystalline structure became more completed (α‐crystal form) in the presence of PEG. Viscoelastic parameters such as zero‐shear viscosity and relaxation time as an indication of elasticity were obtained. The results revealed enhanced polymer chain mobility and disentanglement ought to plasticizing effect of PEG. The critical content of PEG about 20–30 wt % at which the solid–liquid phase separation occurred was in good agreement with the viscoelastic properties. Hence, more than 20% PEG the elasticity diminished and the melt strength became zero. The interfacial tension of the PLA and PEG estimated through the rheological and morphological parameters evidenced the good miscibility of PLA/PEG system at the melt electrospinnig temperature. While the high viscose samples (η₀ > 1800 Pa/s) PLA and PLA/PEG (95/5) were not spinnable at the spinning temperature of 180 °C, blends containing 10–30% PEG were easily spun. The finest and continuous fiber mats were obtained by electrospinning of PLA/PEG (80/20) blend (d_f = 4.8 ± 0.8 μm). More than the critical concentration of PEG (Φ > 30%), lacking the elasticity suppressed the melt electro‐spinnability of PLA/PEG. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 44120.     

Electrolytically exfoliated graphene–polylactide‐based bioplastic with high elastic performance

This work reports an innovative way to prepare biopolymer composite by incorporating graphene (GP) synthesized from electrolytic exfoliation into biodegradable polymer blend (polylactide/epoxidized palm oil: PLA/EPO) based on melt‐blending method and studies their physical properties for food packaging and related applications. Multilayer GP structure synthesized by electrolytic exfoliation is confirmed by transmission electron microscopy and Raman spectroscopy, whereas homogeneous GP incorporation in PLA/EPO is verified by scanning electron microscopy and X‐ray diffraction. From thermogravimetric analysis and heat deformation temperature (HDT) studies, the decomposition and HDTs of PLA/EPO/GP composites are higher than those of PLA/EPO but are lower than those of pristine PLA and tend to decrease with increasing GP content because of thermal conductivity effect. From standard tensile test, loading of GP in PLA/EPO at an optimal concentration of 0.6 wt % results in higher elongation at break by as much as 52%. The observed additional elongation under a given tension and the corresponding lower tensile strength/Young's modulus may be attributed to lower binding force of materials in the composite because of the presence of relatively weak GP–PLA/EPO interfaces. Moreover, oxygen permeability is found to decrease with increasing GP contents and oxygen permeability is reduced by 40.33% at the GP loading concentration of 0.6 wt %. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41439.     

Mechanical and thermal characterization of compression moulded polylactic acid natural fiber composites reinforced with hemp and lyocell fibers

This research evaluates the effects of PLA/PP blend ratio and Lyocell/hemp mixture ratio on the morphology, water absorption, mechanical and thermal properties of PLA‐based composites. The composites were fabricated with 30 mass % hemp using compression moulding. As a reference composites made from PP were also studied. Combining of hemp and Lyocell in PLA composite leads to the reduction of moisture absorption and can improve the impact, tensile, flexural properties when compared with PLA/hemp. Composite based on the PLA/PP blend‐matrix could not improve the tensile and flexural properties compared with PLA/hemp, however; the lighter composite with better impact properties was obtained. The crystallization temperature of the PLA‐PP/hemp increased compared with pure PLA. This result was also confirmed by the SEM micrographs. The moisture absorption of PLA‐PP/hemp was higher than PLA/hemp. Based on theoretical analysis of DMTA data, there was favorable adhesion in all composites. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40534.     

Thermal and dynamic mechanical properties of polyethylene glycol/quartz composites for phase change materials

Polyethylene glycol (PEG)/quartz (denoted as BP/Q) composites have been investigated as candidates of phase change materials (PCMs) due to their thermomechanical properties around the glass transition temperature as well as thermal properties between 30 and 600 °C. Quartz (q-SiO₂) powders were extracted from local sand in Tanah Laut, Pelaihari, South Kalimantan, Indonesia. The composites were prepared by dispersing q-SiO₂ powders in the PEG matrix followed by the wet mixing process. The thermal properties of the composites were characterized using differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA), while the thermomechanical properties were examined using a dynamic mechanical analyzer (DMA) in a three-point bending mode around the PEG glass transition temperature range (−100–50°C). The morphology and interface bonding were investigated using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). From the DSC measurement, the endothermic peak of the composites showed a shift of approximately 7–12 °C toward higher temperatures than that of the pure polymer. The melting enthalpy values (ΔH_m) of the BP/Q composites covered the required PCM application range, that is, between 139 and 182 J/g. The TGA of the composites showed that thermal degradation occurs in the range of 250–450 °C. We found that solid–solid PCMs (ssPCMs) were successfully fabricated with the addition of 10 and 20 wt% q-SiO₂. From DMA characterization, the BP/Q 20 wt% composite exhibited the maximum E’ and the minimum energy dissipation (E”). Its E’ value was approximately 250 MPa more than that of the pure PEG. The glass transition (T_g) temperatures of PEG and BP/Q composites (5, 10, and 20 wt%) were around −24.5, −19.1, −17.1, and − 5.3 °C, respectively. In addition, the E” and tan δ values decreased with q-SiO₂ filler content. Furthermore, the Cole-Cole plots of the BP/Q composites revealed a better interfacial bonding between the q-SiO₂ and the PEG matrix in the composites with higher silica content. A compact morphology was shown by the BP/Q 20 wt% composite due to high silica concentration. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 48130.     

聚乙二醇改性聚乳酸/乙酰柠檬酸三丁酯复合薄膜的结构及性能

以聚乳酸（PLA）为基材、乙酰柠檬酸三丁酯（ATBC）为增塑剂、聚乙二醇（PEG）为增韧剂采用溶液共混法涂覆制备PLA复合薄膜。采用红外吸收光谱、热分析、X射线衍射、扫描电子显微镜及拉伸测试表征PLA复合薄膜的结构和性能。结果表明,适量的PEG改性PLA/ATBC复合薄膜后,使其拉伸强度从29.52 MPa增加到33.40 MPa,断裂伸长率从262 %增加到292 %,薄膜的柔韧性得到增强;PEG的端羟基与PLA的羰基发生缔合反应形成氢键,提高了PLA/ATBC复合薄膜的热稳定性和结晶度;观察90 d后的薄膜表面SEM图像,发现PEG改性后的PLA/ATBC复合薄膜表面没有龟裂纹的产生,延长了其使用寿命;加入微量的爽滑剂乙撑双硬脂酰胺（EBS）改善了PLA复合薄膜的相容性和加工性能。     

High thermally conductive PLA based composites with tailored hybrid network of hexagonal boron nitride and graphene nanoplatelets

Bio‐based polymers and multifunctional polymeric composites are promising for the development of new environmentally sustainable materials and are becoming increasingly popular compared to their oil based counterparts. This research aims to develop new multifunctional bio‐based polymer composites with improved thermal conductivity and tailored electrical properties to be used as heat management materials in the electronics industry. A series of parametric studies were conducted to clarify the science behind the hybrid composites' behavior and their structure‐to‐property relationships. Using bio‐based polymers [e.g., polylactic acid (PLA)] as the matrix, heat transfer networks were developed and structured by embedding hexagonal boron nitride (hBN) and graphene nanoplatelets (GNP) in a PLA matrix. The effects of random uniform thermal hybrid networks of hBN‐GNP on improving the effective thermal conductivity (k_eff) of produced composites were studied and compared. Composites were characterized with respect to physical, thermal, electrical, and mechanical properties for practical application in the electronics industry. The use of high thermally conductive hybrid filler systems, with optimized filler content, was found to promote the composites' effective thermal conductivity to more than 12 times over neat PLA. The thermally conductive composite is expected to provide unique opportunities to injection mold three‐dimensional, net‐shape, lightweight, and eco‐friendly microelectronic enclosures with superior heat dissipation performance. POLYM. COMPOS., 37:2196–2205, 2016. © 2015 Society of Plastics Engineers     

Morphology,biodegradability, mechanical,and thermal properties of nanocomposite films based on PLA and plasticized PLA

In this study, melt intercalation method is applied to prepare poly(lactic acid) (PLA) and poly(ethylene glycol) (PEG)‐plasticized PLA nanocomposite films including 0, 3, and 5% organoclay (Cloisite 30B) using a laboratory scale compounder, which is connected to a microcast film device. To evaluate the nanomorphology and the dispersion state of the clays, X‐ray diffraction (XRD) and transmission electron microscopy (TEM) are conducted. Tensile tests are performed to characterize the mechanical behavior of the films. Biodegradation rate is determined by degradation tests in composting medium. Differential scanning calorimeter (DSC) is applied to observe the thermal behavior of the films. XRD and TEM show that the exfoliation predominantly occurrs in plasticized PLA nanocomposites, whereas unexfoliated agglomerates together with exfoliated clays are observed in the nonplasticized PLA. Tensile tests indicate that the addition of 3% clay to the neat‐PLA does not affect the strength; however, it enhances the modulus of the nanocomposites in comparison to neat‐PLA. Incorporation of 3% clay to the plasticized PLA improves the modulus with respect to PLA/PEG; on the other hand, the strain at break value is lowered ～ 40%. The increase in the rate of biodegradation in composting medium is found as in the order of PLA > PLA/PEG > 3% Clay/PLA/PEG > 5% Clay/PLA/PEG > 3% Clay/PLA. DSC analysis shows that the addition of 3% clay to the neat PLA results in an increase in T_g. The addition of 20% PEG as a plasticizer to the neat‐PLA decreases T_g about 30°C, however incorporation of clays increases T_g by 4°C for the plasticized PLA. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

A thermoplastic polyurethane/rare earth composite film with adjustable fluorescence colors and optimal low-temperature flexibility

In this study, a unique series of luminous polymeric rare earth (RE) composite films was produced by loading RE ions into thermoplastic polyurethane (TPU) using solution blending. Compared to RE ions, luminous polymeric RE composites had greater luminescence intensity, indicating that the introduction of polymer polyurethane as the polymer matrix was advantageous for the luminescence intensity and efficiency of RE ions, with the polymer matrix's absorbed energy being transferred to the RE ions. Furthermore, the findings of the optical transmittance, UV–visible absorption and fluorescence emission spectra suggest that TPU-RE composite films possess exceptional fluorescence luminescence properties and optical transparency. Surprisingly, the fluorescence colors of TPU-RE fluorescent films could be adjusted between red and green by varying the ratios of Eu³⁺ and Tb³⁺ in the films and can be any mixture of red and green hues. In addition, the temperature at 5% weight loss (T_5%) for the TPU-RE composite film composition reached 250 °C. In addition, pure TPU and all TPU-RE hybrid films demonstrated a glass transition temperature (T_g) of about −30 °C. Simultaneously, the tensile strength of the TPU-T₀E₁₀ film reached its maximum (43.6 MPa). Consequently, the TPU-RE composite films will be utilized as photoluminescent functional materials. © 2022 Society of Industrial Chemistry.     

Role of Mn of PEG in the morphology and properties of electrospun PEG/CA composite fibers for thermal energy storage

As an aim toward developing novel class of form‐stable polymer‐matrix phase change materials for thermal energy storage, ultrafine composite fibers based on cellulose acetate and polyethylene glycol (PEG) with five different molecular weight (M_n) grades were prepared by electrospinning. The effects of M_n of PEG on morphology, thermal properties and mechanical properties of the composite fibers were studied by field emission scanning electron microscopy, differential scanning calorimetry, and tensile testing, respectively. It was found that the composite fibers were smooth and cylindrical shape, with the average diameters ranging from about 1000 to 1750 nm which increased with M_n of PEG. Thermal analysis results showed that the composite fibers imparted balanced thermal storage and release properties in different temperature ranges with the variation of M_n of PEG. Thermal cycling test indicated that the prepared composites had excellent thermal stability and reliability even they were subjected to 100 heating‐cooling thermal cycles. © 2009 American Institute of Chemical Engineers AIChE J, 2009