纤度和预氧化处理对酚醛纤维性能的影响

将热塑性酚醛树脂通过熔融纺丝的方法制备了不同纤度的酚醛纤维原丝,并经后固化处理得到了交联的酚醛纤维,考察了酚醛纤维纤度与纤维拉伸强度和溶失率之间的关系,以及预氧化处理对酚醛纤维残碳率和耐热性的影响。研究结果表明,在一定范围内,经同样固化工艺处理的酚醛纤维的拉伸强度随纤度的减小而明显增大,而溶失率随纤度的减小而减小;经过预氧化处理过的酚醛纤维结构上引入更多交联点,当纤维在220℃处理30 min后,其强度和残碳率均达到最大值,并且纤维的耐热性能得到显著提高。

Effect of fineness and pre-oxidation treatment on characterization of phenolic fibers

Phenolic fibers (PF) with varying fineness were prepared by fiberizing a melt of phenolic resin to obtain uncured phenolic resin fibers which were subsequently treated to cure. The influence of PF filaments fineness on tensile strength and weight loss ratio,the effect of pre-oxidation treatment on the carbon yield ratio and thermal stability were investigated.The results showed that with decreasing fineness of filaments,the tensile strength of phenolic fibers cured by the same process was significantly increased to a limited extent,but the weight loss ratio was declined.More cross-link points were brought into the structure of phenolic fibers after pre-oxidation.Both tensile strength and carbon yield ratio of phenolic fibers were improved greatly and the maximum could be obtained under condition of the pre-oxidation'temperature of 220℃ and the time of 30 minutes,while the thermal stability was greatly improved simultaneously.