C. K. Abdullah

A review on chitosan-cellulose blends and nanocellulose reinforced chitosan biocomposites: Properties and their applications

Chitin is one of the most abundant natural polymers in world and it is used for the production of chitosan by deacetylation. Chitosan is antibacterial in nature, non-toxic, and biodegradable thus it can be used for the production of biodegradable film which is a green alternative to commercially available synthetic counterparts. However, their poor mechanical and thermal properties restricted its wide spread applications. Chitosan is highly compatible with other biopolymers thus its blending with cellulose and/or incorporation of nanofiber isolated from cellulose namely cellulose nanofiber and cellulose nanowhiskers are generally useful. Cellulosic fibers in nano scale are attractive reinforcement in chitosan to produce environmental friendly composite films with improved physical properties. Thus chitosan based composites have wide applicability and potential in the field of biomedical, packaging and water treatment. This review summarises properties and preparation procedure of chitosan-cellulose blends and nano size cellulose reinforcement in chitosan bionanocomposites for different applications.

Empty Fruit Bunches as a Reinforcement in Laminated Bio-composites

In this article, we study laminated bio-composites that were reinforced with empty fruit bunches. Five-ply veneer laminated bio-composites were prepared by alternately arranging oil palm trunk veneer and empty fruit bunch mat. Composites were made with a gluing layer of 250 or 450 g/m2 of phenol formaldehyde. The mechanical, physical, and thermal (TGA) properties of the composite were studied. Results indicated an improvement in mechanical, physical, and thermal properties of the laminated bio-composites with the use of empty fruit bunches as reinforcement. The water absorption and thickness swelling of laminated bio-composites that were reinforced with empty fruit bunches were better than bio-composites not reinforced with empty fruit bunches. Laminated bio-composites with the use of empty fruit bunch as reinforcement showed better bending strength, bending modulus, and screw withdrawal. Thermal stability for laminated bio-composites with empty fruit bunch also improved. Images taken with a scanning electron micrograph indicated an improvement in the fiber-matrix bonding for the laminated panel glued with 450 g/m 2 of phenol formaldehyde.

Properties enhancement of resin impregnated agro waste: oil palm trunk lumber:

In this study, the kiln-dried oil palm trunk (OPT) was impregnated with phenol formaldehyde (PF) and urea formaldehyde (UF) resin as a matrix using high-pressure vaccum impregnation chamber. Different percentages of resin were loaded in oil palm trunk lumber (OPTL) and compared with kiln-dried OPT and rubberwood (RW). The physical, mechanical, and environmental properties were studied according to BS and ASTM standards. The morphology of resin-loaded OPTL was analyzed by scanning electron microscopy (SEM), while thermal characterization was carried out by thermogravimetric analysis. In general, the OPTL exhibited better values of physical and mechanical properties than dried OPT and OPTL (50% resin loading), which were slightly lower than RW; however, OPTL exhibited good thermal stability compared with dried OPT and RW. Furthermore, the OPTL exhibited a high resistance against termites. The observation of SEM micrograph showed that OPTL with PF resin loading exhibited better morphology than OPTL with UF resin loading, and full penetration of resin into OPT structures was observed.

Physical and thermal properties of microwave-dried wood lumber impregnated with phenol formaldehyde resin

In this study, microwave-dried oil palm trunk core lumber was impregnated with phenol formaldehyde resin using high pressure vacuum chamber. The impregnation of oil palm trunk core lumber was performed under 3 bar pressure and cured in an oven at 150℃ for 2 h. The impregnation of oil palm trunk core lumber was carried out at different time intervals (15, 30, 60, 90, 120 min) to obtain different density lumber and compared with microwave-dried oil palm trunk core lumber and rubberwood. The physical and thermal properties of microwave-dried oil palm trunk core lumber, impregnated oil palm trunk core lumber and rubberwood were studied. In general, the impregnated oil palm trunk core lumber obtained better physical properties than microwave dried oil palm trunk core lumber but slightly lower than rubberwood. The thermal stability of oil palm trunk core lumber was analyzed by using thermogravimetric analysis and it shows that rubberwood exhibited better thermal stability than impregnated oil palm trunk core lumber.