Abstract
The composites were prepared by molding coconut fiber with either polylactic acid (PLA) or polybutylene succinate (PBS) in the cyclohexanone and characterized. Formulations of the composites (types of biodegradable polymer and ratios of fiber to polymer) were optimized. Physical and mechanical properties,including water content, microscopic examinations by CCD and SEM, apparent density, and mechanical properties of coconut fiber, polymers and composites were investigated. The incorporation of the PLA and PBS polymers to coconut fiber significantly improved the physical and mechanical properties of the composites. Both PLA and PBS polymers produced composites with similar appearances. Increasing polymer contents essentially increased the apparent density, flexural strength and modulus of elasticity, and all samples exhibited enhanced adhesive properties. However, increasing more polymer contents could adversely affect the composite preparation, particularly the difficulty of mixing and homogeneity. Generally, composites made from PLA had almost the same flexural strength at break and modulus of elasticity when compared to those of PBS composites at certain polymer concentrations. Nevertheless, thin film layers of some PBS composites may clearly be appeared if higher polymer contents were used, as examined by CCD. The composite with approximately 50% PLA and the coconut fiber of 50% has been satisfied our requirements of physical characteristics and mechanical properties.
