摘要
将均苯四甲酸二酐(PMDA)/4,4′-二苯醚二胺(ODA)/2-对氨基苯基-5-氮基苯并咪唑(PABZ)共聚体系的聚酰胺酸(PAA)溶液进行湿法纺丝,制成PAA纤维,采用热亚胺化的方法制得聚酰亚胺(PI)纤维。研究了不同的纺丝及其后处理条件对PI纤维结构性能的影响。结果表明:当聚合物中PABZ含量较高时,PAA初生纤维拉伸比较高,热亚胺化温度高,PI纤维的力学性能显著提高。当PABZ/ODA摩尔比为7/3,PAA初生纤维拉伸比为2.48,热处理温度512℃,处理时间5 min时,PI纤维力学性能最好,其拉伸强度和初始模量分别为10.2,322 cN/dtex,PI纤维热性能较好,在510℃左右仍有较好的热稳定性,其玻璃化转变温度为410～433℃。扫描电镜观察和广角X射线衍射分析表明,较高的热亚胺化温度会导致PI纤维内部出现裂纹,结晶度较低为16.63%。
The copolymer system of pyromellitic dianhydride （PMDA）/4,4＇-oxydianiline （ODA）/2-aminopbenyl-5-aminobenzimidazole （PABZ） dissolving in polyamic acid （PAA） solution was spun into PAA fiber via wet spinning process. The polyimide （PI） fiber was obtained from PAA fiber after thermal imidization. The effects of different spinning and after treatment conditions on the structure and properties of PI fiber were studied. The results showed that the as-spun PAA fiber needed relatively high draw ratio and thermal imidization temperature and the mechanical properties of the PI fiber was greatly improved at relatively high PABZ content in the eopolymer system. The mechanical properties of PI fiber were optimized when the PABZ/ODA mole ratio was 7/3 ,the draw ratio of as-spun PAA fiber 2.48, heat treating temperature 512 ℃ and time 5 rain. The tensile strength and initial modulus of PI fiber reached 10.2 and 322 eN/dtex,respeetively. The PI fiber was thermally stable at about 510 ℃ and had the glass transition temperature of 410 -433 ℃. The scanning electron microscopy observation and wide X-ray diffraction analysis showed that the interior cracks of the PI fiber formed, resulting from the relatively high thermal imidization temperature. The erystallinity was 16.63%.
出处
《合成纤维工业》
CAS
CSCD
北大核心
2008年第4期1-4,共4页
China Synthetic Fiber Industry
基金
国家自然科学基金重点项目(50433010)
关键词
聚酰亚胺纤维
聚酰胺酸纤维
力学性能
热性能
结构
polyimide fiber
polyamie aeid fiber
meehanieal properties
thermal property
strueture
