碳纳米管改性氟橡胶的性能研究

开展了碳纳米管材料对氟橡胶复合材料的改性研究,探究碳纳米管含量对氟橡胶复合体系物理性能、热性能、微观结构形貌、透气性以及宏观力学性能的影响。在此基础上模拟高温高压条件进行老化试验,对老化试验前后材料的硬度变化、体积变化、拉伸性能、撕裂性能和压缩永久变形量进行了测量与分析。结果表明,拉伸强度和撕裂强度随碳管含量增加表现增加的规律,基于脆断表面和热失重断面证实了本文实现了高含量碳纳米管的均匀分散,并且一维纳米材料构筑的碳纳米管网络结构有助于氟橡胶复合材料气体阻隔性能提升;基于老化前后的性能对比数据,表明碳纳米管的存在有助于老化后氟橡胶宏观性能的保持。     

On the separation of physical and chemical component of stress relaxation

This paper proposes a new method to separate physical and chemical components of stress relaxation. The stress relaxation measurements of tetrafluoroethylene-propylene rubber were carried out at various temperatures ranging from 200° to 310°C. A physical stress relaxation master curve could be generated from data of early period of time by the time-temperature superposition principle. The rate of physical stress decay at given temperatures was calculated from the master curve. The rate of chemical stress relaxation was given by subtracting the rate of physical decay from experimentally obtained rate at the corresponding temperatures. The activation energy was found to be 8.4 kcal mol^?1 for the rates of the calculated chemical stress relaxation, while it was found to be 5.7 kcal mol^?1 for the rates which were obtained in air. The results show that the physical component of stress decay should be subtracted from the measured stress relaxation curve to obtain the rate of chemical stress decay, especially at the low temperature.     

氟橡胶耐高温酸碱性能的研究

研究氟橡胶（FKM）的耐高温酸碱性能.对氟橡胶标准试样的力学性能、老化性能、耐酸碱腐蚀性能进行分析,结果表明：FKM胶片分别在100℃、质量分数为40%氢氧化钠溶液及100℃、质量分数为20%盐酸溶液中浸泡24 h,标准试样力学性能均有下降,但胶片能够达到高温耐腐蚀.进一步研究得出：BaSO4 10份、不添加硅藻土时,橡胶的耐碱性能最好,其拉伸强度达13.33MPa;BaSO4 10份、硅藻土5份时,橡胶的耐酸性能相对较好.     

Effect of solution concentration on the properties of nanocomposites

Though a large number of nanocomposites prepared by solution process has been reported in the literature, effect of solution concentration on properties of the nanocomposites has not been studied. In the present work, new fluorocarbon–clay nanocomposites were prepared by a solution mixing process. Characterization of the nanocomposites was done with X‐ray diffraction technique and atomic force microscopy. Effects of different rubber‐solution concentrations (5, 10, 15, 20, and 25 wt %) on the mechanical and dynamic mechanical properties of the resultant nanocomposites were investigated. Optimum properties were achieved at 20 wt % solution. The data could be explained with the help of structure of the nanocomposites and dispersion of the clay. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 2407–2411, 2006     

PLV85540型氟醚橡胶的单体组成、分子链结构和热学性能

采用红外(FTIR)、氢谱核磁(1 H-NMR)、氟谱核磁(19 F-NMR)和凝胶渗透色谱(GPC)对PLV85540型氟醚橡胶的单体组成和分子链结构进行了系统分析和计算,采用热失重分析(TGA)和差示扫描量热法(DSC)对其热学性能进行了测试。在分析与测试的基础上,明确了PLV85540型氟醚橡胶的组成结构和氟醚单体对其热学性能的影响。结果表明,PLV85540型氟醚橡胶是由偏氟乙烯(VDF)、四氟乙烯(TFE)、全氟甲基乙烯基醚(MVE)、全氟烷氧基乙烯基醚(MOVE)和含乙烯基的硫化点单体(c.s.m)组成的五元共聚物。经计算可知,VDF含量约为57.3%,TFE含量约为20.5%,MVE含量约为6.5%,MOVE含量约为15.6%,c.s.m含量约为0.1%。MOVE的加入使PLV85540型氟醚橡胶的耐低温性能进一步提升,玻璃化转变温度可达-40℃;同时,由于主链中的结构并未被破坏,所以其热稳定性也得到了保持,热分解温度为430℃。     

Structure-property relationship of specialty elastomer-clay nanocomposites

The present work deals with the synthesis of specialty elastomer [fluoroelastomer and poly (styrene-b-ethylene-co-butylene-b-styrene (SEBS)]-clay nanocomposites and their structure-property relationship as elucidated from morphology studies by atomic force microscopy, transmission electron microscopy and X-ray diffraction and physico-mechanical properties. Due to polarity match, hydrophilic unmodified montmorillonite clay showed enhanced properties in resulting fluoroelastomer nanocomposites, while hydrophobic organo-clay showed best results in SEBS nanocomposites.     

PFOA替代品研究及其在氟橡胶中的应用

针对全氟辛酸（PFOA）可能引发的环境和健康问题,开发出了一种复配型的表面活性剂FS。对FS的表面性能和在氟聚合物中的适用性进行了研究,并对比了PFOA体系和FS体系在氟橡胶聚合中的应用数据,结果表明,采用FS体系后,氟橡胶的性能没有明显改变,仍然能适应生产和客户应用的需要,可以作为PFOA在氟橡胶中的替代品。     

双酚AF/BPP硫化体系对氟橡胶2462性能的影响

研究了双酚AF和BPP对氟橡胶2462性能的影响。结果表明,随着双酚AF用量的增大,胶料的最大转矩逐渐增大,强度变化较小,硫化胶压缩永久变形降低,脆性温度呈下降的趋势;随着BPP用量的增加,胶料的焦烧时间和正硫化时间缩短,硫化胶压缩永久变形增大,脆性温度逐渐升高,但是由于BPP对交联密度的提高贡献不大,因此硫化胶的力学性能变化不明显。     

Effect of carbon black loading on fluoroelastomer–solvent interactions

An analysis of the molecular transport of organic liquids into fluoroelastomer membranes containing varying amounts of carbon black has been undertaken by the sorption–desorption gravimetric method. The variation in carbon black loading and temperature showed a significant effect on their transport characteristics. Diffusion coefficients were calculated from Fick's equation. Experimental sorption–desorption results were analyzed in terms of concentration profiles obtained from a solution of Fick's equation as well as by a numerical method based on the finite difference technique. Arrhenius activation parameters were estimated from the temperature-dependent diffusion and permeation data. The results of this study are discussed in terms of polymer–solvent interactions. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 68:815–825, 1998     

高性能特种弹性体的拓展(四)——氟橡胶(1)

综述近年来在非轮胎橡胶制品领域拓展应用的具有特殊性能和特种用途、能在苛刻条件下使用的高性能特种弹性体.本综述第4部分介绍氟橡胶的发展历程和分类,详述在通用氟橡胶(1型和2型氟橡胶)基础上拓展的高性能氟橡胶的组成和特性.这些高性能氟橡胶包括高氟含量氟橡胶、过氧化物硫化氟橡胶、耐低温氟醚橡胶(3型氟橡胶)[全氟甲基乙烯基醚...