Modifications of Coir by Grafting for Use in Composites

Abstract

<span style="font-size:11.0pt;line-height:115%; font-family:" calibri","sans-serif";mso-ascii-theme-font:minor-latin;mso-fareast-font-family:="" calibri;mso-fareast-theme-font:minor-latin;mso-hansi-theme-font:minor-latin;="" mso-bidi-font-family:timesnewromanpsmt;mso-ansi-language:en-us;mso-fareast-language:="" en-us;mso-bidi-language:ar-sa"="">Coir fibres were modified by treatment with alkali and graft copolymerization with methyl methacrylate MMA using eerie ammonium nitrate and nitric acid as initiator. The conditions for grafting of MMA on the coir fibres were optimized by studying the effect of <i>p</i>H, monomer and initiator concentration, time and temperature of graft copolymerization reaction on <span style="font-size:11.0pt;line-height: 115%;font-family:" calibri","sans-serif";mso-ascii-theme-font:minor-latin;="" mso-fareast-font-family:calibri;mso-fareast-theme-font:minor-latin;mso-hansi-theme-font:="" minor-latin;mso-bidi-font-family:arialmt;mso-ansi-language:en-us;mso-fareast-language:="" en-us;mso-bidi-language:ar-sa"="">% <span style="font-size:11.0pt; line-height:115%;font-family:" calibri","sans-serif";mso-ascii-theme-font:minor-latin;="" mso-fareast-font-family:calibri;mso-fareast-theme-font:minor-latin;mso-hansi-theme-font:="" minor-latin;mso-bidi-font-family:timesnewromanpsmt;mso-ansi-language:en-us;="" mso-fareast-language:en-us;mso-bidi-language:ar-sa"="">graft add-on. An increase in density, denier and initial modulus and a decrease in tenacity and moisture regain of coir fibres were observed by grafting MMA. Hybrid composites were fabricated using glass, coir fibres and a 50:50 blend of unsaturated polyester resin USP and unsaturated urethane acrylate styrene resin crestomer. An improvement in flexural strength, flexural modulus and interlinar shear strength was observed when alkali-treated or coir-g-MMA fibres were used as reinforcement.</span></span></span>