【摘要】 研究了热处理时不同的温度、时间及张力对Lyocell纤维结构和性能的影响。结果表明热处理能提高Lyocell纤维的强度和模量,但是断裂伸长率有所下降。热处理温度为160℃,时间为12～25s时效果较好。热处理中施加张力可以进一步提高Lyocell纤维的强度和模量,但纤维的断裂伸长率迅速下降。热处理后的Lyocell纤维结晶度略有提高,但随着张力的增加,结晶度基本不变。热处理后纤维的总取向增大,而晶区取向基本不变,故无定形区取向大幅度提高。研究结果还表明Lyocell纤维通过热处理而提高的力学性能并不能长久地维持,随着放置时间的延长,其力学性能会逐渐下降并回复到热处理以前的状态。更多还原

【Abstract】 In this paper, the effects of temperature, time and tension of heat treatment on the structure and mechanical properties of Lyocell fibers were investigated. The results show that the tensile strength and initial modulus of treated Lyocell fiber increase slightly, whereas the elongation at break decreases. It is found that the mechanical properties of fiber reach maximum when the treat temperature is 160℃ and the processing time is 12～25s. Moreover, applying tension on the fiber during the heat treatment could improve further the tensile strength and initial modulus of Lyocell fiber, while the elongation at break of fiber decreases at the same time. The results show the crystallinity of heat-treated fiber increases slightly and it has no obvious change with the increase of tension. In addition, the general orientation of heat-treated fiber increases and the crystalline orientation is unchanged, the amorphous orientation improves accordingly. It is also found that the improved mechanical properties of Lyocell fiber by heat treatment can’t be reserved for long. The mechanical properties of fiber would decline with time and it would revert to the state before heat treatment.更多还原