【摘要】 通过在线监测聚丙烯腈(PAN)纤维的热收缩应变和应力,研究了硼酸改性对PAN纤维预氧化的影响。试验结果表明:随着硼酸溶液浓度的增加,PAN纤维化学反应的起始和结束温度向高温方向移动,化学收缩量降低,预氧化纤维体密度逐渐降低,硼酸对PAN纤维化学反应有抑制作用;硼酸对分子内环化和分子间交联反应的抑制可有助于预氧化纤维均质化程度的提高,并可防止PAN纤维表面在较高温度下被过度氧化。更多还原

【Abstract】 Through in-situ measuring the shrinkage strain and stress of polyacrylonitrile(PAN) fiber,the effects of boric acid on pre-oxidation of PAN fiber were studied.The results indicated that with the increasing of the concentratin of boric acid,the initial and end temperature of chemical reactions would move to high temperature,the chemical shrinkage would reduce and density of the oxidized fiber would decrease.Boric acid could inhibit chemicals reactions of PAN fiber during stabilization.However,the suppression on intramolecular cyclization and intermolecular crosslinking reaction of boric acid could help to improve the degree of homogenization of pre-oxidized fiber.And PAN fiber surface could be prevented from being excessively oxidized at the higher temperature.更多还原