聚酰亚胺干法纺丝油剂的研制

研制了一种适用于干法纺聚酰亚胺纤维工艺的油剂,其原料廉价易得,使用效果好。性能测试表明:该油剂具有较好的抗静电性能、摩擦性能、润湿性能和热稳定性能,使用该油剂得到的成品纤维的性能指标要优于使用日本进口油剂的纤维。     

干法纺聚酰亚胺纤维的结构与性能

以均苯四甲酸二酐、4,4'-二氨基二苯醚、3,3'-二氨基二苯醚为原料,以N,N-二甲基乙酰胺为溶剂,制得聚酰胺酸(PAA)纺丝液,采取干法纺丝制得PAA初生纤维,将PAA初生纤维经过300~380℃的热处理后,得到聚酰亚胺(PI)初生纤维,在400℃下对PI初生纤维进行热拉伸,最终得到PI纤维,研究了热处理温度、热拉伸倍数等对PI纤维的结构与性能的影响,比较了PI纤维与P84纤维和芳纶1313的性能。结果表明:在300~380℃的热处理温度下,随着温度升高,PI纤维的力学性能降低,最佳热处理温度为300℃时制得的PI初生纤维于400℃下进行热拉伸3.0倍,所得PI纤维的断裂强度为5.8 c N/dtex,初始模量为69.4c N/dtex,其力学性能优于P84纤维及芳纶1313;PI纤维在空气中失重5%和10%的温度分别为560,570℃,其起始分解温度高于P84纤维和芳纶1313,热性能更好;PI纤维经高温热拉伸,纤维内部分子链沿纤维轴向高度取向,表现出典型的取向诱导结晶效应。     

干法纺聚酰亚胺纤维生产技术的研发

阐述了干法纺聚酰亚胺(PI)纤维生产技术的研究过程、技术方法,并介绍了该纤维的主要特性。综述表明,干法纺PI纤维生产技术是针对湿纺技术生产效率低、成本高、溶剂回收困难等缺点而创新发展的新技术,具有聚合原液国产化制备并可随机调控,纺丝过程的因素可控性,纤维的拉伸、环化过程一体化设计等技术关键点和创新点。其纤维产品有更优异的热稳定性、低温稳定性、永久阻燃性、化学稳定性和电绝缘性。指出干法纺PI纤维生产技术对打破国外技术壁垒,以及对我国高性能纤维产业结构调整和优化升级具有重要战略意义。     

腈纶NaSCN湿法纺丝与杜邦干法纺丝的比较

本文主要把腈纶ＮａＳＣＮ湿法与杜邦干法纺丝在工艺过程、成形机理、工艺参数及纤维结构等方面进行比较，进而总结了两种纺丝方法的不同特点。     

腈纶干法纺丝油剂的国产化研制

提出了干法腈纶纺丝油应具备的使用性能标准,通过实验应用性能对比,验证了国产油剂良好的使用性能,为进一步开展工业应用试验提供了基础。     

影响干法氨纶中残留溶剂含量的因素

考察了甬道温度、原液质量分数、纺丝速度、单丝纤度、喷丝孔形状等对氨纶丝残留溶剂含量的影响。结果表明:在甬道长度恒定的情况下,甬道温度的增加、纺丝速度的降低以及单丝纤度的减少都有利于降低氨纶丝中残留溶剂的含量;原液质量分数对残留溶剂含量的影响则比较复杂,原液质量分数35%时,残留溶剂含量随原液质量分数的升高而降低,而原液质量分数35%时,残留溶剂的含量随浓度的升高而升高;另外,选择合适形状的喷丝板也有利于降低残留溶剂的含量。     

干法纺丝聚(苯并咪唑-酰亚胺)纤维的制备及性能研究

以3,3',4,4'-联苯四甲酸二酐为二酐单体,对苯二胺和2-(4-氨基苯基)-5-氨基苯并咪唑为二胺单体,在非质子溶剂中合成前驱体聚酰胺酸,采用干法纺丝、热环化及热拉伸制备聚(苯并咪唑-酰亚胺)(简称聚酰亚胺)纤维(PI纤维),研究了不同拉伸倍数下的PI纤维的结构及性能。结果表明:PI纤维表面光滑致密,截面为肾形;随着拉伸倍数提高,PI纤维的取向度和力学性能提高;当拉伸倍数为6.35时,其取向因子为0.81,拉伸强度为2.31 GPa,拉伸模量达到117.0 GPa;随着拉伸倍数提高,PI纤维的玻璃化转变温度(T_g)逐渐降低,T_g为324~342℃;PI纤维在500℃以上开始热分解,具有良好的热稳定性能。     

干法腈纶纺丝油剂单体的国产化研究

通过试验产品与国产其它同类产品分析数据的对比,试验在理化指标和复配及腈纶丝上油使用测试指标上达到了进品４１２＃单体的指标要求,可以替代进口产品。还了本项目工业化生产的可行性与经济效益预测。     

油剂对干法腈纶丝束加工性能的影响

通过比较3种不同油剂的组成、性能,分析了油剂对干法腈纶丝束上油率及加工性能的影响。A- 60日本复合油剂的附着性、丝束上油效果、丝束加工性能最好,17-20油剂次之,100国产复合油剂最差。丝束含油率为0．25％～0．45％时,丝束的加工性能较好。     

The effect of carbon fiber content on the friction and wear properties of carbon fiber reinforced polyimide composites

The current study examines the tribological performance of polyimide and carbon fiber reinforced polyimide (CF/PI) under dry sliding condition. Different contents of carbon fibers were employed as reinforcement. All filled and unfilled polyimide composites were tested against CGr15 ball and representative testing was performed. The effects of carbon fiber content on tribological properties of the composites were investigated. The worn surface morphologies of neat PI and its composites were examined by scanning electron microscopy and the wear mechanisms were discussed. Moreover, all filled polyimides have superior tribological characteristics to unfilled polyimides. The optimum wear reduction was obtained when the content of carbon fiber is 20 vol %. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Influences of different imidization conditions on polyimide fiber properties and structure

In the present work we prepared co-polyimide (PI) fibers with excellent mechanical and dielectric properties by the wet-spinning method. The co-PI fiber exhibited high mechanical property with a tensile strength of 2.61 GPa and modulus of 86.7 Gpa as well as a low dielectric constant and a dielectric loss factor of 2.7463 and 0.00793 at 10 GHz, respectively. The relationship between the properties and the microstructure of co-PI fibers after heat-drawing was investigated. The results revealed that the hydrogen-bond associations and the microvoids structure were highly affected by imidization conditions. Both the formations of the hydrogen-bond associations and the evolution of microvoids were attributed to the change in tensile strength. Furthermore, the fibers prepared at proper conditions possessed fewer surface defects as well as homogeneous inner structure. Our work demonstrates the structure–property relationship in annealed PI fibers, which may provides a new avenue to access high-performance PI fibers.     

干纺工艺对聚酰亚胺初生纤维生产及其性能影响研究

试验研究探讨了聚酰亚胺干法纺丝工艺对初生纤维生产和性能的影响因素。结果表明,纺丝温度在200~220℃、纺丝风量在12~15 m/m3、纺丝速度≯180 m/min和喷丝板牵伸比21.5时有利于初生纤维的正常生产及其性能的提高。     

The mechanical and thermal properties of graphite fiber reinforce polyphenylquinoxaline and polyimide composites

Comparative studies were made on the fabrication characteristics, mechanical properties and thermal stabilities of three commercially available composite systems based on linear monoether polyphenylquinoxaline, P13N polyimide, and Skybond 703 polyimide, reinforced with Modmor II graphite fibers. Fabrication parameters and prepreg conditions were related to the properties of the laminates. Interlaminar shear strength and flexural properties were evaluated before and after the thermal aging at 600°F for periods up to 500 hrs. Thermal degradation of composites at various stages of thermal' aging was studied using optical and scanning electron microscopes.     

国产耐高温聚酰亚胺纤维的产业化

聚酰亚胺纤维是一种重要的高性能纤维,其中耐高温聚酰亚胺纤维主要应用于环保的过滤领域、热防护等行业。随着高科技产业的发展以及国家对环保要求的不断提高,耐高温聚酰亚胺纤维的市场需求量将不断扩大。高琦公司整合多方优势,努力推进国产耐高温聚酰亚胺纤维的产业化进程,打破国外的垄断格局,极大的推动了我国高性能纤维行业的科技进步。     

聚酰亚胺初生纤维存放过程中结构与性能的变化

采用传统二步法合成部分成环的聚酰亚胺预聚体,经湿法纺丝得到聚酰亚胺初生纤维,探讨了纤维结构与性能随存放时间的变化。结果表明:室温下聚酰亚胺初生纤维的强度与模量随存放时间的延长明显降低,但在-15℃下,力学性能基本保持不变。初生纤维在室温下存放60d,其热分解温度从567.1℃降到了558.0℃。低温下放置可抑制初生纤维力学性能的衰减。     

聚酰亚胺薄膜及纤维的探索研究

利用均苯四甲酸二酐(PMDA)、4,4'-二氨基二苯醚(4,4'-ODA)和自制三单体在强极性非质子有机溶剂N,N-二甲基乙酰胺(DMAc)中进行共缩聚反应,制得高粘度的聚酰胺酸(PAA)溶液,经涂膜、热亚胺化,得到坚韧透明的聚酰亚胺(PI)薄膜,其具有较好的拉伸断裂强度和合适的伸长率;同时将得到的PAA溶液进行湿法纺丝,制成PAA纤维,采用热亚胺化和高温拉伸的方法制得PI纤维,其断裂强度能达到3.67cN/dtex。