Koay Seong Chun

Mechanical and thermal properties of coconut shell powder filled polylactic acid biocomposites: effects of the filler content and silane coupling agent

The effects of the filler content and the coupling agent 3-aminopropyltriethoxysilane (3-APE) on the mechanical properties, thermal properties, and morphologies of polylactic acid (PLA)/coconut shell powder (CSP) biocomposites were investigated. It was found that increasing the CSP content decreased the tensile strengths and elongations at break of the PLA/CSP biocomposites. However, incorporating CSP increased their modulus of elasticity. The tensile strengths and modulus of elasticity of the PLA/CSP biocomposites were enhanced by the presence of 3-APE, which can be attributed to a stronger filler–matrix interaction. The thermal stabilities of the biocomposites increased with the filler content, and they were enhanced by 3-APE treatment. Meanwhile, the presence of CSP increased the glass transition temperatures (Tg) and crystallinities (Xc) of the PLA/CSP biocomposites at a filler content of 30 php. After 3-APE treatment, Tg and Xc of the PLA/CSP biocomposites increased due to enhanced interfacial bonding. The presence of a peak crystallization temperature (Tc) for the PLA/CSP biocomposites indicated that the CSP has a nucleating effect. The melting temperatures (Tm) and the Tc values of the biocomposites were not significantly affected by the filler content and 3-APE. PLA/CSP biocomposites that had been treated with 3-APE presented the strongest filler–matrix interaction, as confirmed by SEM.

Characterization and Properties of Recycled Polypropylene/Coconut Shell Powder Composites: Effect of Sodium Dodecyl Sulfate Modification

This research work focuses on the utilization of coconut shell powder (CSP) as filler in recycled polypropylene (rPP). Sodium Dedecyl Sulfate (SDS) was used as coupling agent in these composites. The effect of filler content and SDS on tensile properties, thermal properties, water absorption and morphology of rPP/CSP composites were investigated. In this study, modified rPP/CSP composites with SDS show significant increased tensile propertied, thermal stability, crystallinity and low water absorption compared unmodified rPP/CSP composites. Those improvements were contributed by the coupling effect of SDS.

Polylactic acid/corn cob eco-composites: Effect of new organic coupling agent

A new organic coupling agent called coconut oil coupling agent (COCA) was produced from coconut oil. The effects of filler content and COCA on mechanical, thermal, and morphological properties of corn cob (CC)-filled polylactic acid (PLA) eco-composites were studied. The results show that the addition of CC decreased the tensile strength and elongation at break but increased the modulus of elasticity of PLA/CC eco-composites. However, the presence of COCA improved the tensile strength, elongation at break, and modulus of elasticity of PLA/CC eco-composites. Meanwhile, the glass transition temperature (T g) of PLA/CC eco-composites was increased by increasing the CC content and COCA treatment. The peak crystallization temperature (Tc ) in PLA/CC eco-composites indicated the nucleating effect of CC and the Tc of PLA/CC eco-composites decreased at 40 php of CC content. The addition of CC increased the melting temperature (Tm ) of PLA/CC eco-composites but reduced the crystallinity of PLA/CC eco-composites. The COCA treatment enhanced the mechanical properties and the crystallization process of PLA/CC eco-composites. The Tc and Tm of PLA/CC eco-composites were not significantly affected by COCA treatment. The presence of COCA improved the adhesion and interaction between CC and PLA matrix.

Utilization of cocoa pod husk as filler in polypropylene biocomposites: Effect of maleated polypropylene

The aim of the research was to utilize cocoa pod husk (CPH) in polypropylene (PP) biocomposites. Maleated polypropylene (MAPP) was used as coupling agent to improve the properties of PP/CPH biocomposites. The addition of MAPP had increased the stabilization torque of PP/CPH biocomposites. The tensile strength and modulus of PP/CPH with MAPP were higher compared to PP/CPH biocomposites without MAPP, except the elongation at break decreased. The crystallinity and thermal stability of PP/CPH biocomposites with MAPP increased. These improvements were due to the enhanced interfacial bonding between CPH and PP matrix, which were proved by SEM analysis.

Green composites from kapok husk and recycled polypropylene: Processing torque, tensile, thermal, and morphological properties

The present work was developed to utilize kapok husk (KH) as filler in recycled polypropylene (rPP) green composites. Stearic acid (SA) was used as surface modifier in rPP/KH composites. It was found that the modified KH with SA was reduced the stabilization torque of composites. The addition of KH in rPP decreased the tensile strength and elongation at break but increased tensile modulus of composites. The modified KH with SA improved the tensile strength, tensile modulus, crystallinity, and thermal stability of composites. The scanning electron microscopic micrograph provd that the interfacial interaction and adhesion was improved by SA modification.

Agrowaste-based composites from cocoa pod husk and polypropylene: Effect of filler content and chemical treatment

Cocoa pod husk (CPH)-filled polypropylene (PP) composites were prepared via melt compounding. The effect of filler content and chemical treatment using 3-mercaptopropyltrimethoxysilane (MPS) and sodium dodecyl sulfate (SDS) on properties of composites were investigated. The results indicated that the treated composites with MPS and SDS improved the tensile strength, tensile modulus, thermal stability, stabilization torque, water resistivity, and crystallinity of composites. The treated composites with SDS show better tensile properties and water resistivity than composites treated with MPS. Scanning electron microscopic results show that the interfacial bonding between CPH and PP matrix improved with the presence of MPS or SDS.

Tensile Properties of Polypropylene/Cocoa Pod Husk Biocomposites: Effect of Maleated Polypropylene

Polypropylene/Cocoa Pod Husk (PP/CPH) biocomposites with different maleated polypropylene (MAPP) content were prepared via melt blending process using Brabender Plastrograph mixer. The tensile strength and tensile modulus of PP/CPH biocomposites increased with increasing of MAPP content. The PP/CPH biocomposites with 5 phr of MAPP showed the optimum improvement on tensile properties. However, the increased of MAPP content reduced the elongation at break of PP/CPH biocomposites. At 5 phr of MAPP content, PP/CPH biocomposites showed lowest elongation at break. Scanning electron microscope confirms the PP/CPH biocomposites with MAPP have better filler-matrix interaction and adhesion due to the effect of MAPP.

Torque rheological properties of polypropylene/cocoa pod husk composites

The torque rheological properties of plastic wood composites are important to practical processing, but the research in this field is rare. In present, a Brabender plastrograph torque rheometer was used to analyse the rheological behavior of polypropylene (PP)/cocoa pod husk (CPH) composites. The effect of processing parameter, filler content, and addition of maleated polypropylene (MAPP) on torque rheological properties was investigated. The torque rheological data found that the processing torque increased with the increases of rotor speed, filler content, and addition of MAPP. The PP/CPH composites melt behavior as pseudoplastics and shear thinning occurred at higher shear rate. The decrease of power law index (n) evidenced the pseudoplasticity of PP/CPH composites increased at higher filler content and presence of MAPP. The increase of viscosity on PP/CPH was due to filler–filler interaction at higher filler content and strong filler–matrix adhesion after addition of MAPP. The activation energy of PP/CPH composites also increased with higher amount of CPH and addition of MAPP.

Comparison study on green coupling agents from different type of plants oil for agrowaste-based thermoplastic composites

In the present work, a different green coupling agent (GCA) was developed from virgin coconut oil (GCA-C). The GCA-C were a kind of glycidyl fatty acid ester which are reactive to natural filler. A comparison between GCA made from palm oil (GCA-P) and coconut oil (GCA-C) was studied. The results indicated the tensile strength and tensile modulus of composites increased with increasing the GCA content, and the 3 wt% of GCA content was the optimum content to achieve maximum improvement. Meanwhile, the increased GCA content slightly reduced the elongation at break of composites, but the elongation at break increased at 5 wt% of GCA content. The GCA-C had better performance in improving interfacial adhesion compared to GCA-P due to different fatty acid content. The micrographs of scanning electron microscope evidenced that the modified cocoa pod husk (CPH) with 3 wt% GCA had better filler–matrix adhesion with polypropylene matrix.

Properties of kapok husk-filled linear low-density polyethylene ecocomposites Effect of polyethylene-grafted acrylic acid

This research focuses on utilization of kapok husk (KH) as a natural filler in linear low-density polyethylene (LLDPE) ecocomposites. The effect of KH content and coupling agent on tensile properties, thermal properties, water absorption behavior, and morphology of ecocomposites were studied. The addition of KH had increased tensile modulus and water absorption of ecocomposites, whereas tensile strength and elongation at break decreased. However, the polyethylene-grafted acrylic acid (PEAA) was used as a polymeric-coupling agent to enhance the properties of LLDPE/KH ecocomposites. The incorporation of PEAA improved the tensile strength, tensile modulus, crystallinity, and thermal stability as well as reduced the water absorption of LLDPE/KH ecocomposites. The improvement of those properties was caused by the enhanced interfacial bonding, which was evidenced by scanning electron microscopy. The Fourier transmission infrared spectra also confirmed the presence of ester linkage between PEAA and KH.