The influence of fibre treatment on the performance of coir-polyester composites

Surface modifications of coir fibres involving alkali treatment, bleaching, and vinyl grafting are made in view of their use as reinforcing agents in general-purpose polyester resin matrix. The mechanical properties of compos ites like tensile, flexural and impact strength increase as a result of sur face modification. Among all modifications, bleached (65 degreesC) coir-pol yester composites show better flexural strength (61.6 MPa) whereas 2% alkal i-treated coir/polyester composites show significant improvement in tensile strength (26.80 MPa). Hybrid composites comprising glass fibre mat (7 wt.% ), coir fibre mat (13 wt.%) and polyester resin matrix are prepared. Hybrid composites containing surface modified coir fibres show significant improv ement in flexural strength. Water absorption studies of coir/polyester and hybrid composites show significant reduction in water absorption due to sur face modifications of coir fibres. Scanning electron microscopy (SEM) inves tigations show that surface modifications improve the fibre/ matrix adhesio n. (C) 2001 Elsevier Science Ltd. All rights reserved.