Combined effect of water retting and Sodium Hydroxide Concentration on properties of Luffa cylindrica fibres

Abstract

Luffa cylindrica is an annual climbing plant whose fruit has a vascular network of fibres. These fibres are held together by pectins which degrade during water retting to release the fibres. In this paper, the extraction of luffa cylindrica fibres together with the combined effect of water retting and alkali treatment on its tensile properties are reported. The fibres were extracted from mature fruits of Luffa cylindrica through aerobic water retting process over a duration of 2 weeks, 4 weeks and 8 weeks. The extracted fibres were oven dried to a moisture content of 9.74±1.1% and tested in tension at gauge lengths of 10 mm. The fibres were characterized in terms of moisture regain, lignin content, hemicellulose content, and cellulose content. The combined effect of water retting and sodium hydroxide (NaOH) concentration on the fibre’s breaking load, elongation, tenacity and linear density was also investigated. The luffa cylindrica fibres had a moisture regain of 10.81%, lignin content of 12.03%, cellulose content of 65.69%, and hemicellulose content of 19%. The linear density of the fibres retted for 2-8 weeks was 572–470 dTex .The determined breaking load of the fibres retted for 2-8 weeks was 1444.19-417.04 cN and 997.81-298.05 cN after treatments with 0% -16% NaOH. The fibre elongation was 4.0-24% after 2-8 weeks of retting and 4.3-14.5 % after treatments with 0% -16% NaOH. Tenacity of luffa cylindrica fibres was 6.0-25.25 cN/Tex after 2-8 weeks of retting and 5.9-20.22 cN/Tex after treatments with 0% -16% NaOH. From the study, an increase in aerobic water retting and concentration of NaOH had a positive effect on the tensile properties of the luffa cylindrica fibres.