摘要
采用不同浓度的硫酸对聚丙烯腈(PAN)预氧化纤维进行处理。介绍了硫酸对PAN预氧化纤维的作用机理,探讨了硫酸浓度和处理时间对PAN预氧化纤维结构和质量的影响。通过扫描电镜(SEM)观察并定量评价纤维皮芯结构。借助傅里叶变换红外光谱(FTIR)和X射线衍射(XRD)手段对硫酸处理的PAN预氧化纤维的化学组成和晶体结构进行表征。结果表明:PAN预氧化纤维经过不同浓度硫酸处理后,通过SEM能够观察到预氧化纤维的皮芯结构,经98%硫酸处理2 min后出现孔洞,在10 min后芯部比例为10.9%,趋于稳定;在硫酸处理过程中,纤维中氰基发生水解,环化结构(C=C/C=N)特征吸收峰因化学环境的改变而红移;PAN微晶结构受到硫酸破坏,预氧化纤维环化结构仍然保存。
Pre-oxidized polyacrylonitrile （PAN） fiber was treated with sulfuric acid with different concentration. The working mechanism of sulfuric acid on pre-oxidized PAN fiber was introduced. The effects of sulfuric acid concentration and treating time on the structure and mass of pre-oxidized PAN fiber were discusssed. The skin and core structure of the fiber was observed and quantitatively evaluated by scanning electron microscopy （SEM）. The chemical composition and crystalline structure of the sulfu- ric acid-treated pre-oxidized PAN fiber were characterized by Fourier transform infrared spectroscopy （FTIR） and X-ray diffrac- tion （XRD）. The results showed that the skin-core structure of pre-oxidized PAN fiber formed after treating with sulfuric acid of different concentration; the core of pre-oxidized PAN fiber appeared when the fiber was treated with 98% sulfuric acid for 2 min, and the core ratio remained stable at 10.9% after 10 min; the nitrile groups were hydrolyzed during sulfuric acid treatment, which caused red shift in characteristic absorption peak of the cyclization structure （C=C/C=N） ; and the microcrystalline structure of PAN was destroyed by sulfuric acid when the cyclization structure of the pre-oxidized PAN fiber still remained.
出处
《合成纤维工业》
CAS
2015年第4期8-11,共4页
China Synthetic Fiber Industry
基金
国家重点基础研究发展计划(2011CB605602)
关键词
聚丙烯腈纤维
预氧化纤维
皮芯结构
硫酸刻蚀
polyacrylonitrile fiber
pre-oxidized fiber
skin-core structure
sulfuric acid etching
