聚酰亚胺(PI)纤维是一种新型高性能纤维,具有耐高低温、高强高模、耐辐照、阻燃、绝缘、低的吸水率和优异的介电性能等。以PI的预聚体—聚酰胺酸溶液为纺丝液,采用具有自主知识产权的一体化连续纺丝技术,通过化学结构设计和纺丝工艺控制,开发出耐高温、高强中模、高强高模等系列高性能PI纤维产品,最高强度和模量分别达到4.0 GPa和160 GPa。与芳纶纤维、超高分子量聚乙烯纤维等相比,PI纤维显示出优异的耐高温、耐紫外、耐酸性能和较低的吸水率。以高强高模PI纤维为增强体,制备了热固性环氧树脂基体及热塑性尼龙基体复合材料,分析其性能,结果表明纤维与树脂基体之间具有良好的界面性能。针对热塑性复合材料,PI纤维的加入使复合材料的强度和韧性均得到大幅提高,PI纤维将在航空航天、电力、防护、环保、核工业等领域有广阔的应用前景。
Aromatic polyimide (PI) fiber is considered as a kind of novel high performance fiber due to its outstanding high and low temperature resistance, high strength and high modulus, radiation and flame resistance, insulation, low water absorption, and dielectric property. Using polyamide acid as spinning solution, we prepared a series of high performance PI fibers with high temperature resistance, high strength and middle modulus, high strength and high modulus by molecular design and spinning technology con- trol using a continuously manufacturing method, and the highest strength and modulus attained 4.0 GPa and 160 GPa respectively. Compared with aramid fibers and ultra-high molecular weight polyethylene fibers, the PI fibers have excellent high temperature resistance, ultraviolet resistance, acid resistance, and low water absorption. The PI fibers with high strength and modulus were used to reinforce epoxy and polyamide resins, and the results show that there is good interface property between resins and fibers. The addtion of PI fibers improve the strength and toughness of the thermoplastic composites, so it has broad application in aerospace, power, environmental protection, nuclear industry, and other fields.