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环氧大豆油无溶剂法合成研究 总被引:14,自引:0,他引:14
介绍了一种环氧大豆油的无溶剂法合成工艺.通过正交实验方法优选了合成工艺条件;讨论了甲酸用量、双氧水用量及滴加速度、催化剂用量、反应温度、反应时问等对产物环氧值的影响。 相似文献
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以环氧大豆油和甲醇为原料,通过开环加成制备植物油基多元醇。在自制的二氯二氧化钨(WO2Cl2)作催化剂、三氟甲磺酸银(Ag OTf)作助催化剂的条件下,考察了催化剂用量、助催化剂用量、反应时间、温度和醇油物质的量比等对环氧大豆油开环转化率的影响,并对产物的环氧值进行了测试。结果表明,当催化剂用量为3%(以甲醇和环氧大豆油总质量为基准,下同),三氟甲磺酸银用量为4%,反应温度为70℃,反应时间为8 h,醇油物质的量比为28∶1时,环氧大豆油的开环转化率较高,为89.13%。对开环产物进行了FTIR、1HNMR、TG以及流变性分析。通过热重分析得出,多元醇的分解温度(334℃)比环氧大豆油的分解温度(305℃)高。流变性分析得出,随着温度的升高,环氧大豆油和多元醇的黏度逐渐下降。在温度较低时,大豆油多元醇的黏度明显低于环氧大豆油的黏度。 相似文献
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The transport properties of ionic liquids (ILs) are crucial properties in view of their applications in electrochem-ical devices. One of the most important advantages of ILs is that their chemical–physical properties and conse-quently their bulk performances can be well tuned by optimizing the chemical structures of their ions. This will require elucidating the structural features of the ions that fundamentally determine the characteristics of the nanostructures and the viscosities of ILs. Here we showed for the first time that the“rigidity”, the order, and the compactness of the three-dimensional ionic networks generated by the anions and the cation head groups determine the formation and the sizes of the nanostructures in the apolar domains of ILs. We also found that the properties of ionic networks are governed by the conformational flexibility and the symmetry of the anion and/or the cation head group. The thermal stability of the nanostructures of ILs was shown to be con-trolled by the sensitivity of the conformational equilibrium of the anion to the change of temperature. We showed that the viscosity of ILs is strongly related to the symmetry and the flexibility of the constitute ions rather than to the size of the nanostructures of ILs. Therefore, the characteristics of the nanostructures and the viscosities of ILs, especially the thermal stability of the nanostructures, can be fine-tuned by tailoring the symmetry and the conformational flexibility of the anion. 相似文献
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催化装置粗汽油回炼技术在有效降低催化稳定汽油烯烃含量的同时,对催化装置产品分布产生明显的影响,继而影响到装置的综合经济效益。本文对不同粗汽油回炼量条件下,催化装置稳定汽油性质和产品分布变化趋势进行分析,对经济效益进行对比,阐明应用粗汽油回炼降低汽油烯烃技术时,要选择合适的操作条件,以期得到较好的综合经济效益。 相似文献
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磷尾矿中元素赋存状态研究方法的探讨 总被引:3,自引:0,他引:3
对磷尾矿中元素赋存状态的一些研究方法进行了讨论,通过讨论对磷尾矿的综合研究、合理开发利用、重新设计选冶工艺流程等领域都具有十分重要的意义。 相似文献