Chan Ming Yeng

Modified Corn Cob Filled Chitosan Biocomposite Films

The present work was investigated the effect of filler content and chemical modification on mechanical, thermal properties and morphology study of CS/CC biocomposite films. The acrylic acid was used as chemical modification of corn cob. The increasing of CC content has decreased the tensile strength and elongation at break, but increased the modulus of elasticity of CS/CC biocomposite films. The modified corn cob with acrylic acid (AA) has enhanced the tensile properties and thermal properties of CS/CC biocomposite films by improving the interfacial interaction. The chemical reaction between acrylic acid and corn cob was confirmed by Fourier transmission infrared (FTIR) and the improvement of interfacial bonding was proven by scanning electron microscopy.

A comparative study of different crosslinking agent-modified chitosan/corn cob biocomposite films

The effect of corn cob (CC) content and crosslinking agent on tensile, morphological, thermal properties, gel fraction and enzymatic degradation of chitosan (CS)/corn cob (CC) biocomposite films was studied. Epichlorohydrin (EP) and adipic acid (ADP) as crosslinking agents were added to improve the properties of CS/CC biocomposite films. The addition of CC decreased the tensile strength and elongation at break, but increased the modulus of elasticity of CS/CC biocomposite films. The EP-modified CS/CC exhibited higher tensile and thermal properties than ADP-modified CS/CC. The formation of crosslinkages between CS and EP or CS and ADP was proven by Fourier transform infrared studies. The modified CS/CC biocomposite films with ADP and EP, respectively, showed better interface interaction, as demonstrated in scanning microscopy electron. Furthermore, the incorporation of CC in CS increased the weight loss of enzymatic degradation of biocomposite films. Moreover, EP-modified CS/CC shows better resistance to hydrolysis in α-amylase enzymatic degradation than ADP-modified CS/CC. The gel fraction of CS/CC biocomposite films increases with the increasing CC content, whereas the gel fraction of modified CS/CC with EP is higher compared to modified CS/CC with ADP. The novelty of our research showed that the modified biocomposite films with EP have the highest tensile and thermal properties, also gel content than others biocomposite films. The biocomposite films modified with ADP confer plasticization effect compared to unmodified and other modified biocomposite films.

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.

Corn cob filled chitosan biocomposite films

Recently, there has been renews interest in chitosan as materials in producing of biocomposite films. The chitosan (CS)/corn cob (CC) biocomposite films were prepared by solvent casting method. The effect of CC content on tensile properties of CS/CC biocomposite films was studied. The tensile strength and elongation at break of CS/CC biocomposite films decreased as increasing of CC content. However, the increasing of CC content was increased the tensile modulus of CS/CC biocomposite films. Scanning electron microscopy (SEM) was indicated that the deceasing of tensile properties was due to the poor interfacial adhesion between CC filler and CS matrix.

Effect of Cross-linking Agent on Tensile Properties of Chitosan/Corn Cob Biocomposite Films

Glutaraldehyde (GLA) was used as cross-linking agent in chitosan (CS)/corn cob (CC) biocomposite films. The effect of GLA content on tensile properties of CS/CC biocomposite films was studied. The CS/CC biocomposite films were produced through solvent casting method. The tensile strength of modified CS/CC biocomposite films were increased with GLA content and the optimum increment at 1% of GLA content. Similar, modulus of elasticity of biocomposite films increased with GLA content. In contrast, the elongation at break of modified CS/CC biocomposite films reduced as increasing of GLA content. The modified CS/CC biocomposite films with 1% of GLA exhibited the highest elongation at break. The Fourier transform infrared (FTIR) results showed the presence of imine bonds (C=N) and ethylenic groups (C=C) due to the cross-linking reaction occurred between CS and GLA. Furthermore, GLA was enhanced the wettability and interfacial interaction between CS matrix and CC filler, as proven by a morphology study. GRAPHICAL ABSTRACT

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.

Tensile and water absorption properties of solvent cast biofilms of sugarcane leaves fibre-filled poly(lactic) acid

This research covers the preparation of poly(lactic acid) (PLA)/sugarcane leaves fibre (SLF) biofilms via a solvent-casting method. The results showed that the tensile strength and Young’s modulus of PLA/SLF biofilms increased with the increasing of SLF content. Nevertheless, the elongation at break showed an opposite trend as compared to tensile strength and Young’s modulus of biofilms. Moreover, water absorption properties of PLA/SLF biofilms increased with the increasing of SLF content. In contrast, the tensile strength and Young’s modulus of biofilms were enhanced after bleaching treatment with hydrogen peroxide on SLF, but the elongation at break and water absorption properties of bleached biofilms were reduced due to the improvement of filler–matrix adhesion in biofilms. The tensile and water properties were further discussed using B-factor and Fick’s law, respectively. Furthermore, the functional groups of unbleached and bleached SLF were characterized by Fourier transform infrared analysis.

Properties and characterization of wood plastic composites made from agro-waste materials and post-used expanded polyester foam

Recently, many agricultural waste were left for open burning or as landfill in many agricultural land, for example, coconut shells. Besides, expanded polystyrene (EPS) foam is one of the most used plastic products which mostly ends up in landfilling as many of its products were made for one-time use only. In order to reduce these wastes, this project focuses on the preparation of a new material that is coconut shell powder (CSP)-filled EPS wood plastic composite (WPC). This research investigates the effects of CSP content and alkaline treatment with sodium hydroxide (NaOH) on mechanical and water absorption properties of EPS/CSP WPCs. The mechanical properties, such as tensile strength, Young’s modulus and flexural modulus, increased as the CSP content increased. However, elongation at break and flexural strength decreased with CSP content. Moreover, water absorption of EPS/CSP WPCs showed an increasing trend with CSP content. After alkali treatment, the mechanical properties of EPS/CSP WPCs were enhanced, but the water absorption properties of treated EPS/CSP WPCs were reduced due to the reduction of the –OH groups of CSP. Fourier transform infrared analysis was carried out to measure the functional groups of untreated and treated CSP. The fracture surface of CSP, untreated and treated EPS/CSP WPCs were examined by scanning electron microscopy.

Wood plastic composites made from post-used polystyrene foam and agricultural waste

Ever since the development of lightweight polystyrene foam, the material has become an attractive single-use product packaging in various industries. Despite its high versatilities, post consumed polystyrene foam has very low rate of recycling due to the high cost during transportation and there is hardly any established economical recycling route. The purpose of this research is to investigate the potential of converting the polystyrene foam waste as raw material for producing wood plastic composite (WPC). In the present study, predefined formulation of recycled polystyrene (rPS), durian husk fiber (DHF) and processing aid Ultra-PlastTM WP516 were melt blended with the aid of Haake internal mixer. The homogenous mixtures were subsequently compression molded to form WPC. The effect of material compositions on tensile, thermal, and morphological properties of the rPS/DHF composite was highlighted. The results showed that tensile strength and modulus increase with fiber content, while elongation at break and thermal stability were decreased. With higher loading of Ultra-PlastTM WP516, both tensile and thermal properties decreased. This research found that WPC with optimum strength of 18.8 MPa can be produced from rPS having 60 parts per hundred resin (phr) of DHF and 0.5 phr of Ultra-PlastTM WP516, albeit the measured tensile strength is lower compared to commercial alternatives. The resulting WPC possess great potential in none high strength, structurally demanding application.

Tensile Properties of Recycled Polypropylene (rPP)/Chloroprene Rubber (CR) Blends: Effect of CR Content

Polymer blending is one of the methods used to improve some insufficient properties of conventional polymers. The objective of this work was to study the effectiveness of CR content on the tensile properties and morphology study of recycled polypropylene (rPP)/ chloroprene rubber (CR) blends. The results indicated that the tensile strength and modulus of elasticity of rPP/CR blends decreased, however elongation at break increased as increasing CR content. The morphology study of rPP/CR blends showed the incompatibility between rPP and CR with the detachment of CR particles and CR particles pulled out from rPP surface.