氟醚橡胶的结构和高低温性能研究

文中通过红外谱图、核磁共振谱图、DSC曲线、压缩耐寒系数、TG曲线等测试手段对两种氟醚橡胶Viton GLT与СКφ-260МПАН的结构特性、低温性及耐热性等作了深入研究,并与普通氟橡胶F246进行了对比.试验结果表明,氟醚橡胶低温性能明显优于氟橡胶,高温性能与氟橡胶相当,具有优异的综合性能.     

二硫化钼在氟醚橡胶中的应用

研究了二硫化钼对氟醚橡胶物理性能的影响及其作用机理。结果表明,加入二硫化钼使氟醚橡胶的摩擦因数明显减小;在高温硫化过程中,氟醚橡胶中部分二硫化钼转化成了二氧化钼,硫化胶的热老化性能明显下降。     

新型氟醚橡胶密封材料

介绍了新近研制成功的一种新型低温品级氟醚橡胶密封材料，通过大量的材料性能试验和密封模拟试验证明，新研制的这种新型氟醚橡胶材料具有优异的耐高低温性能，可以作为苛刻工况条件下的密封材料使用。     

氟醚橡胶的耐热性能研究

研究200℃下老化时间对氟醚橡胶耐热老化性能与结构的影响。结果表明:氟醚橡胶老化22d后仍保持优异的物理性能;氟醚橡胶的玻璃化温度、-50℃以上的储能模量不随老化时间的变化而变化,而损耗因子峰值随老化时间的延长呈小幅增大趋势;氟醚橡胶适合用于-50℃以上环境下使用的密封材料。     

氟醚橡胶在醇酯类润滑油中的适应性研究

阐述了氟醚橡胶在醇酯类润滑油中的适应性;主要进行了材料性能考核、不同批次胶料性能研究、不同批次胶料稳定性研究和胶料耐不同润滑油性能研究,并完成了典型零件发动机长期装车考核。结果表明,氟醚橡胶密封制品用于某型发动机具有良好密封性,可在-50℃～200℃下含有腐蚀抑制剂的多元醇酯类润滑油中长期使用。     

耐低温氟醚橡胶补强体系的研究

研究多种填料对耐低温氟醚橡胶性能的影响,结果表明：硅酸钙和喷雾黑是耐低温氟醚橡胶较理想的补强填料,在相同用量下,煤粉补强的胶料耐空气热老化和耐压缩永久变形性能优于喷雾炭黑,高填充量时其补强性能接近喷雾炭黑     

氟橡胶与氟醚橡胶的性能对比研究

对氟橡胶F246、氟醚橡胶VitonGLT和CI\Φ-260MAH的耐高低温性能进行了研究,通过对生胶的热分析和对其硫化胶高低温性能的研究,表明氟醚橡胶在显著改善氟橡胶低温柔顺性的同时,仍具有与氟橡胶相当的耐高温性能。     

填充型氟醚橡胶导热性能研究

以氟醚橡胶为基体.通过添加不同无机导热填料制备填充型导热氟醚橡胶,并考察填料热导率、用量及表面改性处理对氟醚橡胶导热性能的影响.结果表明.填料本身热导率大于21 W·(m·K)-1时对氟醚橡胶导热性能的影响已不明显;增大填料用量可显著提高氟醚橡胶导热性能,但会带来加工和使用性能方面的问题;采用硅烷偶联剂对填料进行表面处理能够增强橡胶与填料间的界面结合,提高氟醚橡胶导热性能.     

氟醚橡胶研究及应用进展

简要综述了国内外氟醚橡胶的发展历程,介绍了氟醚橡胶的结构和性能研究及应用进展,对国内氟醚橡胶未来的研究方向进行了展望.     

氟醚橡胶摩擦磨损性能研究

研究了石墨、碳纤维和聚四氟乙烯不同用量和三者并用对氟醚橡胶摩擦磨损性能的影响,并用SEM对橡胶磨损表面形貌进行了分析。结果表明,石墨和聚四氟乙烯填充的氟醚橡胶以粘着磨损为主,磨损严重,而碳纤维填充的橡胶磨损主要是疲劳磨损,可显著提高氟醚橡胶的摩擦磨损性能。石墨和碳纤维并用可产生协同效应,两者用量均为15份时橡胶摩擦磨损性能较好,此时摩擦系数为0.378,磨损率为5.590×10-8mm3/Nm。     

Effect of chemically modified waste rubber powder as a filler in natural rubber vulcanizates

Waste rubber powder (RP) was subjected to chemical modification by using different concentrations of oxidizing agents such as nitric acid and 30% hydrogen peroxide solution. This treatment leads to introducing some functional groups onto the surface of RP. The chemically modified RP was incorporated in natural rubber mixes either alone or in combination with carbon black (HAF). The physicomechanical properties of NR vulcanizates obtained were studied and compared to NR vulcanizates filled with untreated RP. It was found that the chemically modified RP improves tensile strength and aging resistance of NR vulcanizates compared with untreated RP. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 30–36, 2004     

Effect of electrolyte characteristics on electrowinning of copper powder

This paper is concerned with studying the effect of electrolyte characteristics on the production process of electrolytic copper powder from partially depleted Cu containing synthetic electrolytes by electrowinning technique. The main electrolyte characteristics are temperature, circulation rate, Cu and H₂SO₄ concentrations, residence time in the cell, and utilization of organic bath additives. The process is positively affected by increasing the values of all of the studied parameters except for the addition of organic bath additives, which causes a negative effect. However addition of organic bath additives remarkably increases the degree of refinement of the produced powders. In most cases pure and fine copper powders were obtained with a dendritic shape, as indicated by scanning electron microscope (SEM) analysis.     

镀银铜粉填充型导电硅橡胶的研究

研究了镀银铜粉填充型硅橡胶的导电性能。结果表明 :采用乙烯基三过氧叔丁基硅烷偶联剂对镀银铜粉进行表面处理 ,可改善胶料的混炼工艺性 ,提高镀银铜粉的添加量 ;同时也可提高硫化胶中镀银铜粉与硅橡胶的结合力 ,使表层镀银铜粉颗粒不易脱离 ,相应地提高了硅橡胶的导电稳定性 ;所得镀银铜粉填充型导电橡胶的体积电阻率小于 0 0 1Ω·m。     

以铜矿粉为原料直接生产氯化亚铜

介绍了以铜矿粉为原料，在ＺＨＰ－催化剂作用下生产氯化亚铜的方法。与传统方法相比，该法具有原料价格便宜、反应速度快、操作简单、能耗低、海绵铜可循环使用、铜的利用率高、经济效益和社会效益显著等优点。其产品质量超过了国标ＧＢ１６１９－７９的要求。     

动态硫化聚氯乙烯／再生胶／硫化胶粉共混型热塑性弹性体的研制

对聚氯乙烯（ＰＶＣ）／再生胶（ＲＲ）／硫化胶粉（ＶＲＰ）共混型热塑性体的配方和加工工艺进行了研究。结果表明,在１６０￣１７０℃条件下,采用二阶一段动态硫化法制成的热塑性弹性体,其拉抻强度为８．２ＭＰａ,扯断伸长为２９０％,邵尔Ａ型硬度为７０．５±５,撕裂强度为４３ｋＮ／ｍ Ｂｒａｂｅｎｄｅｒ Ｇａｒｖｅｙ口型挤出均得到了外观较好的挤出物,共混物的热塑性级别为４级。     

非水溶剂法制备纳米铜粉

研究了以甘油作为还原剂,聚乙烯吡咯烷酮（PVP）作为分散剂,在液相甘油体系中还原醋酸铜(或氧化铜、氢氧化铜)制备纳米铜粉的方法。通过实验探索得到了最佳制备工艺条件：50 mL甘油体系中加入适量铜盐并使铜盐和甘油的物质的量比达到1∶[KG-*2]40、同时加入分散剂PVP 0.4～0.6 g,控制温度为475～505 K,快速搅拌反应50～60 min。所得产物通过化学分析,粉末X射线衍射（XRD）、透射电镜（TEM）表征,结果表明产物铜粉纯度比较高,粒径符合纳米材料的要求,并且粒子呈球型分布。     

硫化对镀银铝粉/甲基乙烯基硅橡胶导电复合材料性能的影响

研究了硫化时间、硫化温度、交联剂及助交联剂用量对镀银铝粉/甲基乙烯基硅橡胶(MVQ)复合材料导电性能及力学性能的影响。结果表明,镀银铝粉/MVQ复合材料最佳硫化条件:一段硫化时间为硫化仪所测得的正硫化时间(14min),二段硫化时间为4h,硫化温度为170℃,交联剂2,5-双(叔丁基过氧化)-2,5-二甲基己烷的用量为3份,助交联剂三烯丙基异氰脲酸酯的用量为2份。     

铜粉导电胶的研究

用铜粉、环氧树脂、改性胺类固化剂、硅烷偶联剂、奇士增韧剂、稀释剂等制备铜粉导电胶。比较了铜粉的粒径及添加量、铜粉表面处理、导电胶基料、固化时间等对导电性能的影响,并对导电胶性能进行测试,最终选定最合适的导电胶配方。     

Preparation and mechanical properties of natural rubber powder modified by carbon nanotubes

A suspension of carbon nanotubes in natural latex was obtained by liquid mixing and then was used to prepare powder natural rubber composites modified with carbon nanotubes by means of spray drying process. The composite powders were round‐like and fine, with an average diameter of less than about 5 μm. The dispersion of carbon nanotubes in the rubber matrix was improved remarkably compared with that obtained by the mechanical mixing method. By means of vulcanization tests, it was found that the addition of vulcanizing agent necessary for the powder rubber containing carbon nanotubes should be evidently greater than that in rubber prepared by mechanical mixing, there evidently existed vulcanization reversions for the natural rubber prepared by mechanical mixing, which disappeared in the powder rubber containing carbon nanotubes prepared by the spray drying process. The mechanical properties of the powder natural rubber containing carbon nanotubes were much improved because of the modification effect of carbon nanotubes in rubber. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 4697–4702, 2006