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纳米填料填充氢化丁腈橡胶的性能及压缩形态特征 总被引:3,自引:0,他引:3
研究了不同的炭黑( N 330,N 550,N 770,N 990) 、甲基丙烯酸锌及炭黑N 770 与甲基丙烯酸锌并用填充氢化丁腈橡胶( HNBR) 的性能,用橡胶加工分析仪和透射电镜分析了填料的分散性、形态变化及其与胶料压缩永久变形的关系。结果表明,随炭黑粒径增大,胶料的力学性能有所降低,Payne 效应减小( 即炭黑的分散性变好) ,压缩永久变形减小。炭黑填充胶料具有较好的耐热老化和耐油性能,相比较而言,炭黑N 770 填充胶料的综合性能最好。在填充30 份( 质量) 炭黑N 770 的HNBR 中并用适量的甲基丙烯酸锌,随其用量增加胶料的强度和扯断伸长率明显增大,压缩永久变形增大,Payne 效应变化不大。透射电镜分析结果表明,高温下长时间压缩后,炭黑粒子间的距离缩短,粒子有聚集现象,但粒子本身未发生变形。这表明炭黑填充胶料的压缩永久变形主要源于橡胶分子结构的变化、炭黑粒子的聚集及分布状态的变化。聚甲基丙烯酸锌在HNBR 中的纳米分散性优异。由于压缩后该离聚体粒子易产生滑移、变形和明显的聚集现象,对大分子网络弹性恢复的阻碍作用远高于炭黑,因而胶料的压缩永久变形比炭黑填充者要大得多。 相似文献
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研究改性凯孚碳素作为补强剂在工程机械轮胎胎体帘布胶中的应用。结果表明:填充改性凯孚碳素的工程机械轮胎胎体帘布胶的硫化特性与填充炭黑N660和N774的胶料基本相近,拉伸强度比填充炭黑N660的胶料小,与填充炭黑N774的胶料相近,拉断伸长率大,压缩疲劳温升比填充炭黑N660和N774的胶料低,回弹值比填充炭黑N660的胶料高;改性凯孚碳素填料/炭黑N660并用比为1/1填充胶料的性能与填充炭黑N774的胶料基本相同,可替代工程机械轮胎胎体帘布胶料中的炭黑N774,胶料性能符合企业的控制指标要求。 相似文献
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对比研究炭黑N550和浅色填料(碱性白炭黑AS-70、沉淀法白炭黑255、硅酸铝钾GW-9、硅酸铝钾BS-280和矽丽粉VM-56)填充氢化丁腈橡胶(HNBR)胶料的性能,并制备浅色高性能HNBR密封材料。结果表明:与炭黑N550填充胶料相比,沉淀法白炭黑255填充胶料的门尼粘度明显增大,t10和t90缩短;碱性白炭黑AS-70填充胶料的门尼粘度相差不大,FL和Fmax略增大;其他3种浅色填料填充胶料的门尼粘度、FL和Fmax较小,三者水平相当;浅色填料填充硫化胶的耐热老化性能较好;碱性白炭黑AS-70填充硫化胶的压缩永久变形最小;采用碱性白炭黑AS-70制备的浅色高性能HNBR密封材料综合性能优异且各项性能满足相关标准要求。 相似文献
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研究补强体系、生胶并用和硫化体系对充环烷油的溶聚丁苯橡胶(SSBR)胶料性能的影响。结果表明:对纯炭黑补强体系,炭黑用量为75份的胶料的综合性能较好,两种炭黑并用体系的胶料的综合性能提高,但耐磨性能稍差,对炭黑/白炭黑并用补强体系,白炭黑用量为20份的胶料的综合性能优异,继续增大白炭黑用量,填料分散性和胶料性能下降;SSBR并用20份顺丁橡胶,胶料的压缩生热和滚动阻力降低,耐磨性能提高,耐老化性能优异,其他性能满足使用要求;在硫化体系中硫黄用量对SSBR胶料性能的影响最大,硫黄的适宜用量为1.4~1.6份。 相似文献
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乙烯酮(双乙烯酮)是十分重要的化工中间体,其下游产品较多。江苏某化工厂开发生产乙烯酮(双乙烯酮)下游产品三十多个,年生产规模三万多吨,是国内以乙烯酮(双乙烯酮)为中间体生产精细化学品的综合骨干企业。针对乙烯酮(双乙烯酮)下游产品废水特点,该厂结合企业实际,开展了产品优化,结构调整,清洁生产,资源循环利用,节水降耗等工作,从源头削减了污染物的生产。同时投资二千多万元新建预处理装置三套,6000m3/d废水生化处理装置一套,使全厂乙烯酮(双乙烯酮)下游产品的废水得到了有效的治理。 相似文献
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我厂3号回转窑(Φ4m×60m)生产线在1996年年底由SP窑(产量912t/d)改为NSP窑(产量1320t/d),预分解系统为四级旋风预热器带离线式分解炉 相似文献
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The miscibility of various amorphous polybutadienes with mixed microstructures of 1,4 addition units (cis, 1,4 and trans 1,4) and 1,2 addition units have been investigated. The studies here involved optical transparency, differential scanning calorimetry, and small angle light scattering. It was found that a 90 percent (cis) 1, 4 addition polybutadiene was immiscible with high (91 percent) 1,2 addition polybutadiene. Reduction of the 1,2 content to 71 percent induced an upper critical solution temperature (UCST) with the cis 1,4 polymer. Polybutadienes with 50 percent and 10 percent 1,2 contents were miscible above the crystalline melting temperature of the cis 1,4 polybutadiene. Immiscibility of the 91 percent 1,2 addition polymer was also found with a 10 percent 1,2 polybutadiene. The latter polymer also exhibits an UCST with the 71 percent 1,2 polymer. The results are used to interpret the characteristics of blends of polybutadienes of varying microstructure. 相似文献
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以F类粉煤灰为例,详细介绍了测定粉煤灰中烧失量的步骤、计算数学模型、影响测量不确定度的因素以及各项测量不确定度分量评定,人员、设备、材料、方法、环境都是影响测量不确定的因素。 相似文献
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The objective of the study was to explore the effect of the degree of deacetylation (DD) of the chitosan used on the degradation rate and rate constant during ultrasonic degradation. Chitin was extracted from red shrimp process waste. Four different DD chitosans were prepared from chitin by alkali deacetylation. Those chitosans were degraded by ultrasonic radiation to different molecular weights. Changes of the molecular weight were determined by light scattering, and data of molecular weight changes were used to calculate the degradation rate and rate constant. The results were as follows: The molecular weight of chitosans decreased with an increasing ultrasonication time. The curves of the molecular weight versus the ultrasonication time were broken at 1‐h treatment. The degradation rate and rate constant of sonolysis decreased with an increasing ultrasonication time. This may be because the chances of being attacked by the cavitation energy increased with an increasing molecular weight species and may be because smaller molecular weight species have shorter relaxation times and, thus, can alleviate the sonication stress easier. However, the degradation rate and rate constant of sonolysis increased with an increasing DD of the chitosan used. This may be because the flexibilitier molecules of higher DD chitosans are more susceptible to the shear force of elongation flow generated by the cavitation field or due to the bond energy difference of acetamido and β‐1,4‐glucoside linkage or hydrogen bonds. Breakage of the β‐1,4‐glucoside linkage will result in lower molecular weight and an increasing reaction rate and rate constant. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 3526–3531, 2003 相似文献