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天然橡胶中蛋白质总量的测定 总被引:1,自引:0,他引:1
凯氏定氮法常用于测定橡胶中的蛋白质含量,此法测定结果准确,重现性好,但操作费时,试剂消耗量大,更简便的方法为:在消化阶段用硫酸钾、双氧水作催化剂,消化分解完成后,固定pH值滴定。 相似文献
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脱蛋白天然橡胶(DPNR)是一种性能优异、用途广泛的特种橡胶材料。本文对脱蛋白天然橡胶的国内外研究进展情况进行了论述,提出了脱蛋白天然橡胶生产及应用存在的问题以及前景与展望。脱蛋白天然橡胶有望成为我国当代橡胶工业发展的重要方向之一。 相似文献
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脱蛋白天然橡胶(DPNR)是一种性能优异、用途广泛的特种橡胶材料。本文对脱蛋白天然橡胶的国内外研究进展情况进行了论述,提出了脱蛋白天然橡胶生产及应用存在的问题以及前景与展望。脱蛋白天然橡胶有望成为我国当代橡胶工业发展的重要方向之一。 相似文献
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由日本花王株式会社申请的专利 (专利号 0 0 1 0 4 966,公布日期 2 0 0 1 0 5 1 6)“脱去蛋白质的天然橡胶及其生产方法”涉及一种几乎不含蛋白质的脱蛋白质天然橡胶及其生产方法。该生产方法的要点是 :采用一种蛋白酶和一种特定表面活性剂或几种特定表面活性剂结合处理天然胶乳并分离橡胶颗粒。本发明还提供了提高或降低天然橡胶生胶强度的方法 ,公开了防止天然橡胶引起过敏的方式。脱去蛋白质的天然橡胶及其生产方法$杭州市科技情报研究所@王元荪 相似文献
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Natural rubber dissolved in chloroform was reacted with aqueous NaOH using a phase transfer reagent or with solid NaOH to produce dichlorocarbene modified natural rubber. The 13C n.m.r. spectrum of the 100% modified natural rubber showed the presence of diastereoisomers due to two modes of addition of dichlorocarbene units as previously observed in epoxidation. There was no evidence of cis-trans iso-merisation, occurrence of other side reactions or of chain scission (shown by measurements of intrinsic viscosity). Partially dichlorocarbene modified natural rubber gave rise to a complex 13C n.m.r. spectrum that was assigned in terms of triad structures (for methylene carbon atoms)and pentad structures (for olefinic carbon atoms). Using 13C n.m.r. and measurements of glass transition temperature, it was found that reaction with aqueous NaOH and with solid NaOH both gave a random distribution of dichlorocarbene units, as compared with a block copolymer structure observed by previous workers with dichlorocarbene modified polybutadiene. The thermal stability of natural rubber is intermediate between that of the more stable 100% dichlorocarbene modified rubber and the less stable partially modified rubber. 相似文献
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Blends of ENR (epoxidized natural rubber) with CR (chloroprene rubber) were prepared throughout the composition, and important properties of the vulcanizates, both unaged and aged (air and oil) rubber, were determined. Dynamic measurement showed a single tan δ peak for the blends, and the peak temperature monotonically decreased with increasing CR content, resulting also in an increase of resilience at room temperature. Flex crack resistance of CR above room temperature, and oil resistance of ENR were increased in the blends. 相似文献
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导热硅橡胶的研究进展 总被引:1,自引:0,他引:1
概述了导热硅橡胶的导热模型与导热机理;介绍了国内外导热硅橡胶的研制与开发情况,提出了提高硅橡胶导热性能的三种途径;阐述了导热硅橡胶的应用及发展方向. 相似文献
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导热硅橡胶的研究进展 总被引:1,自引:0,他引:1
概述了导热硅橡胶的导热模型与导热机理;介绍了国内外导热硅橡胶的研制与开发情况,提出了提高硅橡胶导热性能的三种途径;阐述了导热硅橡胶的应用及发展方向。 相似文献
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The use of thermally depolymerised liquid natural rubber as a plasticiser in nitrile rubber has been investigated with special reference to the rheological aspects. A comparative evaluation has been made with dibutylphthalate, the ester-type plasticiser commonly used with nitrile rubber. The study revealed that the use of liquid natural rubber as a plasticiser and viscosity modifier improved the processability of the compounds and also enhanced many of the vulcanisate properties. © of SCI. 相似文献
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