Research On The Structure And Properties Of Hemp That After Steam Explosion And Chemical United Degumming

By far, hemp fiber that applications in the industrial are mainly using chemical degumming, the method needs to acid, alkali, or even high temperature and pressure conditions, so high energy and water consumption, and also has a serious environmental pollution. In order to reduce chemical degumming of environmental pollution and improve quality of hemp fiber, the author uses explosion and chemical united degumming, and research on the structure and properties of hemp fiber after degumming.In the united degumming process, in order to determine the optimal chemical processes, given an orthogonal test design using four factors as follows: cooking temperature, cooking time, additives and blank list. According to analysis of orthogonal text, conclusions can be drawn that cooking temperature is the most important factor in hemp fineness, we can be capable of hemp's end-use, the level of environmental pollution and production costs, thereby to determine the best factor level combination.On the basis of these studies, we tested a series of fibers'structure and properties. Studies have shown that: The cellulose content of hemp that after explosion and chemical co-treated is higher than that after a single chemical degumming, and its fiber surface becomes smooth, crack and groove clear, but the trace metal element content are reduced; after flash explosion, the fibers'crystallinity and degree of polymerization decreased, a single fiber tensile breaking strength and the relative flexural stiffness gone down, fiber flexibility to be improved; by explosion and chemical co-treatment, the surface of hemp fiber frictional properties to change, and the process of flash explosion of hemp little effect on the thermal stability of fibers, fiber showed better moisture absorption and dyeing properties.Using fuzzy comprehensive evaluation method to determine the explosion and chemical united degumming of hemp integrated value, obtained the quality of hemp fiber after explosion and chemical co-treated had roughly as well as that hemp after a single chemical degumming, in the environmental development point of view, explosion-chemical united approach is worthy of application and promotion.