简讯

1998年8月21日在广东省佛山市佛山市电化总厂内召开了“复合纤维改性隔膜工业化试验”评审会,会议邀请了原化工部科技司、天津化工研究院、中国氯碱工业协会的专家,以及氯碱行业的部分行家参加了评审。复合纤维改性隔膜工业化试验,是在锦西化工研究院技术开发中心自行研制的复合纤维SM-Ⅱ改性隔膜,进行了小试的基础     

聚四氟乙烯纤维的制造方法及聚四氟乙烯纤维

本发明提供无需象乳液纺丝法那样使用基质材料就能够制造聚四氟乙烯（PTFE）纤维特别是PTFE长纤维、并且生产率优于包括切膜丝法在内的现有制造方法且能够提高所得纤维的机械特性和直径的自由度的PTFE纤维制造方法。通过在PTFE的熔点以上的温度下对细绳状的含PTFE固形物（第一固形物）进行拉拔加工，使上述第一固形物的直径减小的方法。     

隔膜特性的测定方法

自从氯碱生产使用金属阳极以来,碱金属氯化物隔膜电解槽的发展受到了隔膜特性的限制。本文提出了为估算石棉隔膜的导电和膨胀特性的测定技术。试验用电槽采用4极型工作原理,测定电极和鲁金毛细管也可作为光导元件测定隔膜的厚度。试验用电子线路可以使试验在恒定电流下进行而且估算出电阻电压降。研究了添加聚四氟乙烯粉后石棉隔膜的膨胀量及其导电特性,发现随着聚四氟乙烯添加量的百分比的增加由于膨胀不同将引起隔膜厚度发生变化,使电解进程减缓。具有较高的聚四氟乙烯添加量的百分比的隔膜其导电性较差。在工业氯碱电解中除了电阻特别重要之外,石棉隔膜的膨胀特性也是比较重要的。工业电解槽中采用了形稳性阳极后(DSA),对这一要求更加现实起来。下面叙述的测量方法能快速地测定包括在电解条件下精确厚度在内的隔膜特性。     

热处理石棉隔膜试验结果评价

这份报告概述了热处理石棉隔膜与菲热处理石棉隔膜和改性隔膜对比试验的评价通常改性隔膜在渗透性和尺寸稳定性方面具有较好的性能,因而槽电压低、电流效率高、隔膜寿命长。改性隔膜的性能决定于石棉纤维表面的碱金属硅酸盐组成和隔膜热处理后聚四氟乙烯纤维与石棉纤维的粘结情况。根据PPG公司专利(U.S.P.3991251),藉助热处理不含聚四氟乙烯纤维的普通石棉     

聚合物基锂电池纳米纤维隔膜研究进展

综述了静电纺丝技术工作原理、影响条件及国内外运用该技术制备的锂电池用聚合物纳米纤维隔膜的发展现状，主要包括聚甲基丙烯酸甲酯（PMMA）、聚磺酰胺（PSA）、聚丙烯腈（PAN）、聚偏氟乙烯（PVDF）等聚合物纳米纤维隔膜，介绍了各种聚合物隔膜的特点和性能，并对静电纺丝法制备的隔膜的发展方向进行了展望。     

坚持三项调整 促进氯碱平衡

我国氯碱工业面临着不景气局面,主要原因是低水平重复建设和隔膜法增长过快;氯碱企业多、规模小、技术装备落后;有机氯产品规模小、技术与装备落后等,导致了碱氯失衡,烧碱压库而氯气不足。探讨了氯碱与石油化工相结合的模式,提出了产业结构（技术、产品、规模）调整的思路     

当代国际隔膜法氯碱的发展趋势(一)

本文作者长期从事氯碱行业的科研、生产和规划工作,积累了丰富的经验。我刊曾于1989年第五期发表了他的《国内外氯碱离子膜科研生产近况》一文,在国内氯碱行业中引起反响。自本期起我刊将陆续发表他的姊妹篇《当代国际隔膜法氯碱的发展趋势》。本篇阐述的主要问题有:世界氯碱工业的状况、我国近年来的新进展、隔膜电解工艺的技术进步、金属阳极的技术突破、改性隔膜技术、活性阴极技术、隔膜法的换装可行性探讨、世界工业面临的课题和氯碱发展趋势。该文对推动我国氯碱工业的技术进步具有积极的现实意义。     

节能型隔膜法金属阳极电解槽简述

简要介绍了1974年以来，北京化工机械厂为我国氯碱行业制造节能型隔膜法金属阳极电解槽的发展史。分析了节能降耗槽型及影响电解槽电压的诸多因素。     

聚四氟乙烯/炭黑导电纤维的制备及性能

对炭黑（CB）改性聚四氟乙烯（PTFE）纤维进行了研究描述,将炭黑加入聚四氟乙烯制成纤维,能增加其导电性。试验表明,加入炭黑降低了聚四氟乙烯的储能模量和转化的温度。导电PTFE/CB保持了疏水性的特点。含约5%（质量分数）炭黑的聚四氟乙烯纤维的电阻率约可达到（1.963±0.389）×106Ω.m。扫描电镜结果表明炭黑粒子在聚四氟乙烯微纤维之间的分布相当均匀,而且往往会沿微纤维的方向发展形成面状网络。     

简讯

1、日本氯工程公司愿转让改性隔膜技术1985年11月日本电化学协会举行碱工业年会。江苏省氯碱协会前往参加,并邀请锦西化工研究院杨维驿院长为顾问。会期中曾与日本氯工程公司接触。该公司负责人表示愿意转让改性隔膜技术和熟化炉;提供聚四氟乙烯纤维用作改性剂;并拟在南通市协助改装数台8型槽为 DI 槽。2、沈化“七五”期间重点建设项目列入国家计划沈阳化工厂的金属阳极电解槽、天然气制乙炔、糊树脂与环氧氯丙烷工程经国家计委、化工部审批已被列入国家第七个五年计划。通过上述技术引进与改造     

The Tribological Properties of Oxidation-Treated Carbon Fiber-Reinforced PTFE Composite under Oil-Lubricated Conditions

The effect of air-oxidation and ozone surface treatment of carbon fibers (CF) on tribological properties of CF reinforced Polytetrafluoroethylene (PTFE) composites under oil-lubricated condition was investigated. Experimental results revealed that ozone treated CF reinforced PTFE (CF/PTFE) composite had the lowest friction coefficient and wear. X-ray photoelectron spectroscopy (XPS) study of carbon fiber surface showed that the increase in the amount of oxygen-containing groups enhanced interfacial adhesion between CF and PTFE matrix. With strong interfacial adhesion of the composite, stress could be effectively transmitted to carbon fibers; carbon fibers were strongly bonded with PTFE matrix.     

载体法制备聚四氟乙烯纤维及烧结工艺研究

以载体法制备出聚四氟乙烯纤维(PTFE)/聚乙烯醇(PVA)初生丝,然后对初生丝进行不同时间的烧结,以除去PVA制得PTFE纤维,对PTFE纤维进行不同程度的拉伸,检测不同烧结时间和拉伸倍数对纤维力学性能的影响。     

腐蚀环境中纤维增强聚四氟乙烯复合材料的摩擦磨损性能研究

分别研究了不同含量碳纤维(CF)、玻璃纤维(GF)填充聚四氟乙烯（PTFE）复合材料在硫酸溶液中和干摩擦条件下的摩擦学性能,同时考察了PTFE复合材料在酸中的腐蚀行为,探讨了相关机理。结果表明,在酸中GF能够提高PTFE的耐磨性,比CF在提高PTFE耐磨性方面具有更好的优势。就酸溶液中的耐磨性和耐腐蚀性而言,15 %（质量分数,下同）是填料的最佳含量,此时GF和CF填充的PTFE,耐磨性分别较纯PTFE提高了7.7和4.4倍;当填料的含量超过15 %时,复合材料的耐磨性和耐腐蚀性均下降,主要是由于此时犁削和磨粒磨损是PTFE复合材料的主要磨损机制。由于酸溶液的冷却和润滑作用,硫酸溶液中PTFE复合材料的摩擦因数大幅降低,但酸溶液抑制了对磨面上转移膜的形成。     

Preparation of grafted polytetrafluoroethylene fibers and adsorption of bilirubin

BACKGROUND: A successful hemoperfusion technique requires that the adsorbent for bilirubin should have a high specificity, adsorption capacity and adsorption rate, blood compatibility and no toxicity. Compared with polymer microbeads, polytetrafluoroethylene (PTFE) fibers have many advantages. The aim of the work reported here was to prepare a new polytetrafluoroethylene‐graft‐poly(glycidyl methacrylate)‐block‐polyethyleneimine (PTFE‐g‐PGMA‐b‐PEI) adsorbent for bilirubin based on PTFE fibers by the ⁶⁰Co radiation‐induced graft polymerization of GMA followed by the chemical modification of the epoxy groups on the PTFE‐g‐PGMA fibers with PEI. In addition, the adsorption properties of this novel adsorbent for bilirubin were examined. RESULTS: The highest content of amino groups obtained on the PTFE‐g‐PGMA‐b‐PEI fibers was 1.87 mmol g^?1. The maximum adsorption capacity of the grafted fibers was 9.6 mg g^?1 at pH = 6.5. Bilirubin adsorption on these fibers obeyed the Langmuir model. Also, these fibers possessed the ability to selectively adsorb bilirubin in the presence of bovine serum albumin. CONCLUSION: The PTFE‐g‐PGMA‐b‐PEI fibers have a high adsorption capacity for bilirubin and excellent adsorption properties. In addition, this new adsorbent is inexpensive, easy to prepare and has no toxicity. So the PTFE‐g‐PGMA‐b‐PEI fibers as a biomedical adsorbent are promising for the removal of bilirubin through the hemoperfusion technique. Copyright © 2009 Society of Chemical Industry     

Fiber making directly from poly(tetrafluoroethylene) emulsion

Poly(tetrafluoroethylene) (PTFE) fiber with a superior mechanical property was prepared directly from its emulsion by the novel manufacturing process. The PTFE emulsion turned into a paste when a high shear flow was applied and the paste was extruded through a nozzle into a strand consisting of fine PTFE particles. The diameter of the strand was reduced stepwise by applying the die-drawing process through a conical die at a low temperature. The strand was further die-drawn down at elevated temperatures into fine PTFE fibers with a highly oriented crystalline structure. The crystalline orientation factor of the PTFE fiber reached very close to unity. Although the fibers obtained have a very high tensile modulus, the tensile strength was not as high as that expected from the crystalline orientation, suggesting that the presence of some defects in the PTFE fiber formed in the instantaneous deformation.     

聚四氟乙烯纤维的成型方法

聚四氟乙烯(PTFE)纤维,具有高度的化学惰性、低摩擦系数,极好的绝缘性和高低温稳定性,优良的耐老化性和抗紫外辐射性以及极小的吸水率等优异特性,在材料领域引起广泛关注。该文重点介绍了聚四氟乙烯(PTFE)纤维的几种制备方法,包括膜裂纺丝法、糊状挤压纺丝法、乳液纺丝法、凝胶状挤压纺丝法及PTFE共聚物熔体纺丝法,并展望了我国PTFE纤维的发展前景。     

碳纤维增强聚四氟乙烯耐磨材料的研究

通过冷压成型和烧结固化工艺制备了不同配方下碳纤维增强聚四氟乙类（PTFE）试样，并对其进行了机械性能，耐磨损性能测试，用扫描电镜进行了组织结构观察。结果表明：随着碳纤维质量分数的增加，碳纤维增强PTFE材料的冲击性能有所下降；而拉伸强度和硬度则呈递增趋势，抗磨损性能明显提高；碳纤维与PTFE在偶联剂的作用下能够很好相容。     

Polytetrafluoroethylene nano/microfibers by jet blowing

Polytetrafluoroethylene (PTFE) fluoropolymer exhibits extreme chemical and thermal stability, low friction coefficients and many other exceptional properties. Unfortunately, very high molecular weight PTFE has an extremely high melt viscosity (∼10¹⁰-10¹² poise) and negligible solubility in common solvents. Under tensile stress, molten PTFE elongates and breaks rather than forming fibers and processing it is generally laborious and expensive. We have developed a simple, environmentally friendly, single step, solvent-free technique to process very high molecular weight PTFE inside of a high pressure jet of gases such as nitrogen or argon into mats of micro and nanofibers that are up to several millimeter long. Plasticization of PTFE by the hot, high pressure gases within the jet and extensional stretching in the jet nozzle appear to facilitate fiber formation even at temperatures below the melting point. Polarized Raman spectra demonstrate that the PTFE polymer chains exhibit substantial alignment along the fiber axis. The fibers are produced at a rapid rate and adhere to many different materials, allowing for facile fabrication of surface modifying coatings and dense fibrous mats to control properties such as surface hydrophobicity, drag, and biocompatibility. Jet blowing is also suitable for more conventionally processible polymers and formation of polycaprolactone (PCL) fibers is demonstrated.     

国产聚四氟乙烯纤维的特性与应用

介绍了聚四氟乙烯(PTFE)的化学、物理等特性及其应用。PTFE为大分子线型结构,熔点327℃,分解温度在415℃以上。PTFE纤维具有优良的耐腐蚀性,低摩擦因数,不燃,能耐强酸、强碱、强氧化剂等强腐蚀性试剂或溶剂,耐高、低温性能优良。用PTFE纤维制成的滤材广泛应用于垃圾焚烧、高硫煤除尘等领域。     

Supported Electrospun Ultrafine Fibrous Poly(tetrafluoroethylene)/ZnO Porous Membranes and their Photocatalytic Applications

Supported photocatalytic poly(tetrafluoroethylene) (PTFE)/ZnO porous membranes were prepared by sintering electrospun PTFE/poly(vinylalcohol)/zinc acetate dehydrate composite membranes. Electrospun PTFE membranes were utilized as supports with excellent chemical stability and high specific surface area, while the photocatalyst‐ZnO particles derived from the thermal decomposition of zinc acetate dehydrate were homogeneously immobilized on the surface of ultrafine PTFE fibers. The PTFE/ZnO membranes could be easily recovered and reused after water treatment. PTFE/ZnO membranes are expected to have a wide range of potential applications in photocatalysis and photocatalysis‐membrane reactors, playing the role of a catalyst as well as a selective barrier against contaminants of interest.