In order to overcome the disadvantages of traditional chemical degumming, such as serious pollution and fiber damage, as well as the high cost and time-consuming biological degumming process, hemp bast was degummed with high boiling point alcohol organic solvent to improve degumming selectivity and ensure safety and environmental protection. To solve the problem of insufficient residual glue rate and physical and mechanical properties of hemp fiber after degumming, alkaline sodium salt additives were added to organic solvents to assist degumming. The effects of four different alcohols (ethylene glycol, 1,2-propanediol, glycerol and 1,4-butanediol) and three different alkaline sodium salt (sodium carbonate, sodium bicarbonate and sodium silicate) additives on the degumming effect of hemp bast were studied, and the chemical and physical properties of degummed fiber were compared. The results showed that among the four alcohols, the performance of hemp fiber degummed by ethylene glycol was the best, the lignin removal effect was the best, the residual rubber rate of fiber was 8.67%, but the breaking strength was low, which was 3.92 cN/dtex. Among the three basic sodium salt additives, the residual gum rate of hemp fiber degummed by sodium carbonate assisted ethylene glycol is 7.71%, and the breaking strength is 4.84 cN/dtex, which meets the national standard of refined hemp.
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