红麻纤维苄基化改性

Modification of kenaf fiber by benzylation

运用正交试验研究了NaOH质量分数、氯化苄用量、季铵盐用量、反应温度、反应时间等因素对红麻纤维苄基化改性接枝率的影响。苄基化红麻的最佳工艺为:用30%的NaOH对红麻预先浸润20min后,与8mL的氯化苄、0.1g的相转移剂在100℃下反应2.5h,得到苄基化红麻纤维的接枝率为174%。通过IR、SEM对改性前后的红麻纤维进行微观结构表征和分析,并进行吸水性和耐热性测试。苄基化改性之后,红麻纤维表面羟基发生醚化反应,纤维表面粗糙,结构松散,被大量片状附着物包覆。相比红麻纤维,苄基化红麻纤维的平衡吸水率降低,且更容易碳化,具有一定的阻燃性。

Effects of NaOH concentration, benzyl chloride and quaternary ammonium amount, reaction temperature and reaction time on grafting have been discussed by orthogonal experiment. The optimum conditions were obtained： dipping with 30% NaOH 20 min, kenaf fiber reacted with 8 mL benzyl chloride and 0.1 g quaternary ammonium under 100 ℃ for 2.5 h, grafting rate of the modified fiber reached to 174%. The etherification reaction happened on the surface of kenaf fiber hydroxy after modified by benzylation. The surface became rough and the structure became loosed. The fiber was covered by lots of sheet attachment. Compared with kenaf fiber, the balance bibulous rate of the modified fiber was lower and easier to carbonize, indicating its flame-retardant property after grafting.