摘要
采用硫酸对聚丙烯腈(PAN)热稳定化纤维刻蚀,然后通过SEM观察刻蚀后纤维截面,定量评价皮芯结构。确定浓硫酸刻蚀5min为最佳条件。热稳定化过程中温度和时间能够调控纤维径向结构。在恒温热稳定化时,纤维在较高温度下获得的芯部比例较大;在相同温度条件下,随着热稳定化时间延长,纤维芯部比例逐渐减少,纤维的皮层厚度与t1/2存在线性关系,氧化反应受通过皮层的氧扩散所控制。梯度升温能极大减轻热稳定化纤维的皮芯结构,纤度较小的纤维更易获得均匀的径向结构。
Sulfuric acid was introduced to erode the PAN pre-oxidized fibers.The etched fibers were then monitored by SEM,and the core-skin structure of the fibers was estimated.Etching with sulfuric acid 98%for 5min was the best experiment condition.The skin-core structure of fibers can be controlled by temperature and time in thermal stabilization process.In constant-temperature heat treatment process,the core ratio of fibers decreased with the time.The higher core ratio of fiber could be obtained under higher temperature heat treatment.The skin thickness of fiber grew proportionally to the square root of the oxidation time（t1/2）.The oxidation reaction was controlled by the diffusive transport of oxygen.Gradient-temperature treatment and smaller fineness of fibers could almost weaken the skin-core structure of PAN stabilized fibers.
出处
《化工新型材料》
CAS
CSCD
北大核心
2016年第3期35-37,40,共4页
New Chemical Materials
基金
国家自然科学基金(51503216)
浙江省自然科学基金(LQ16E030003)
国家重点基础研究发展计划(2011CB605602)
关键词
聚丙烯腈纤维
热稳定化
皮芯结构
硫酸刻蚀
碳纤维
polyacrylonitrile fiber
thermal stabilization
skin-core structure
sulfuric acid etching
carbon fiber
