A Study on the Surface Structures of Viscose-based Activated Carbon Fiber by FT-IR Spectroscopy and XPS

Using viscose fiber (VF) as starting material and common steam as activating agent, formation of oxygen structures in activated carbon fiber is investigated. In the preparation of samples, VF was first heated at temperatures between 450℃ and 900℃ in N_2 artmosphere. Then, in a successive activation stage, the product carbonized at 600℃ was activated in steam at 450-900℃ for 30 min, and at 600℃ for 5-30 min. The other carbonization products were activated at 600 and 900℃ for 30 min respectively. The products activated at 900℃ were then activated at 450℃ for 30 min again. The starting materiah carbonized products and all activation products were examined by FT-IR spectroscopy and some products were examined by X-ray photoelectron spectroscope (XPS). And the yields of the carbonized and activated products were calculated. By analysing these spectra, the amount of oxygen-containing functional groups of the activated products attained under various activation time, various activation temperature and     

铜盐对聚丙烯腈预氧化纤维增强作用的研究

聚丙烯腈预氧化纤维(以下简称PANOF)是碳纤维生产过程中的中间产品,其性能的好坏与最终产品碳纤维的优劣密切相关。本文采用热机械分折(TMA)、热失重分折(TGA)、溶胀差示扫描量热分折(SDSC)、X光电子能谱分折(XPS)等实验方法研究了铜盐对PANOF的增强作用。发现Cu~+与PANOF中未环化的氰基有着强烈的相互作用。经铜盐处理后所制得的PANOF,其强度可增加30％。研究结果表明,PANOF得以增强的原因是由于发生了以Cu~+为中心离子,PANOF作为配位体的络合作用。络合配位键的生成使未环化的氰基得以交联,交联网络的形成使PANOF的强度明显提高。     

Effects of Electrochemical Treatment on the Superficial Properties of Rayon-based Carbon Fibers

The development of surface acidity on rayon-based carbon fibers during mild electrochemical treatment was investigated. Conductimetric titration was the primary method used to investigate the functionalities on the carbon fiber surface. The acidity on the surface of the untreated carbon fiber was very low, while for the treated fibers, the acidity increased significantly. Moreover, with the treatment extent proceeded, the acidity on the fiber surface also increased. SEM analysis shows electrochemical treatment under intense treatment degree caused considerable etch on the fiber surface. Cavities and grooves can be observed on the surface via the SEM microphotograph. While in a more mild treatment, electrochemical treatment didn't cause great etch on the surface of the fiber.     

补强粘胶基碳纤维性能的研究

X-Ray衍射、小角X-Ray散射、SEM等方法对补强处理前后的RCF样品进行测试分析,结果表明,补强后的RCF抗拉强度大幅度提高,结晶度增加,表面缺陷减少.     

电化学表面处理对粘胶基碳纤维热稳定性的影响

通过热失重分析研究了在不同电化学表面处理条件下粘胶基碳纤维的热稳定性，实验表明未经表面处理的碳纤维在复合材料中的最高使用温度大约为300℃，而表面处理过的粘胶基碳纤维在复合材料中的最高使用温度下降了。因而在选择电化学表面处理条件时，既要考虑使表面性能提高，也要使纤维的热稳定性没有大的下降。     

预氧化腈纶短纤维的耐酸碱性

本文通过广角 X 射线衍射、纤维力学性能的测定、扫描电镜方法等研究了在不同浓度硫酸及氢氧化钠水溶液、不同处理温度和不同时间条件下,具有不同预氧化程度的预氧化腈纶短纤维耐酸碱的基本行为。探讨了预氧化腈纶短纤维在酸碱水溶液作用下,力学性能下降的机理及纤维预氧化程度对耐酸碱性的影响。     

原丝组成及升温速率对腈纶短纤维预氧化工艺的影响

民用腈纶短纤维经松弛状态下预氧化处理可制备适合纺织加工的阻燃耐热纤维。本文通过力学性能测定、差示量热分析、广角X—射线衍射分析、极限氧指数测定等研究了原丝的共聚组成及升温速率对预氧化工艺及氧化纤维的结构和性能的影响。结果表明在几种原丝中如含有衣康酸组分,由于其在DSC谱图中表现出较展宽的环化放热峰,因而较适合于实际的氧化处理工艺。氧化纤维的表现环化度、芳构化指数以及极限氧指数均随升温速率的降低而增加,但氧化纤维的力学性能亦随之下降,可纺性变差。选择0.5℃/min升温速率,可较理想地得到既满足纺织加工要求又具备优良的阻燃耐热性能的氧化纤维。