The Physical and Chemical Properties of Hemp Fiber Prepared by Alkaline Pectinase-Xylanase System

Abstract

Degumming is the vital and critical step in the preparation of hemp fiber for textile application. However, the traditional chemical degumming processes use large amounts of harmful chemicals, especially strong alkalis, which have caused severe challenges to the environment. The reaction conditions of alkaline pectinase and alkaline pectinase were studied in this research, and the alkaline pectinase-xylanase system was successfully applied to the degumming of hemp fibers at mild conditions (T=55 ℃ and pH=8.0) without strong alkali. A comparative analysis of hemp fibers treated under different conditions showed that the gum removal ratio could reach about 50% within 5.5 h of alkaline pectin-xylanase system degumming, making fiber smoother and stronger. After alkaline pectin-xylanase system treatment (0.6 g pectinase, 0.3 g xylanase, 55 ℃, pH 8.0, 5.5 h), the removal ratio of pectin and hemicellulose reached 75 % and 40 %, respectively. And linear density and tenacity of the fiber was 17.4 dtex and 5.62 cN/dtex, respectively. SEM, FT-IR and XRD analysis furthermore demonstrated the excellent effects of the proposed process. The degumming fiber had better water retention performance (513 %) and moisture sorption (8.9 %), which has more excellent application prospects in the textile industry. Moreover, the method abandons the use of acid and alkali and can provide an eco-friendly degumming process for hemp fiber.