磷钨钒杂多酸论文：磷钨钒杂多酸阻聚性能及应用研究

磷钨钒杂多酸论文：磷钨钒杂多酸阻聚性能及应用研究【中文摘要】杂多化合物是一类含有氧桥的多核配合物,由于具有独特的分子结构及分子易于设计和组装的特点,现已广泛应用于新型高效催化剂、药物、磁性材料、高质子导体、电致变色材料、无机填料添加剂、选择电极以及燃料电池等领域。本文以测定磷钨钒型杂多酸阻聚性能为目标。通过采取分步加入原料、分步酸化、回流煮沸、乙醚萃取的方法制备了四种Dawson型磷钨钒杂多酸H730H2O(标记为Dawson-V1),H814H2O(标记为Dawson-V2),H924 H2O(标记为Dawson-V3), H836H2O(标记为Dawson-V4)和三种Keggin型磷钨钒杂多酸H4PW11V04015H2O(标记为Keggin-V1),H5PW10V2O4023H2O(标记为Keggin-V2),H6PW9V3O4024H2O(标记为Keggin-V3),并对其进行了IR、XRG、TG表征,确定化合物的结构和组成。利用差示扫描量热法(DSC)测定已合成的Dawson型和Keggin型磷钨钒杂多酸对甲基丙烯酸甲酯的阻聚效果。实验结果表明,对同一种杂多酸而言,随着杂多酸样品量的不断增加,反应的速率常数不断减小,阻聚性能越好。对于不同的杂多酸而言,随着杂多酸中钨原子与钒原子数目比例的降低,反应的数率常数随之减小,说明含钒原子数越多的杂多酸阻聚性能越好。从总体上来说Dawson型磷钨钒杂多酸的阻聚性能要优于Keggin型。在阻聚测定结果的实验基础上,选取阻聚性能最优的H836H2O为催化剂,讨论催化剂浓度,反应温度,醇酯物质的量比以及反应时间四个变化因素,制定4因素3水平正交试验方案L9(34),考察反应条件对酯化率的影响。通过实验条件和结果的综合比较从而得出H836H2O通过酯交换法催化合成-甲基丙烯酸丁醇酯的最佳反应条件为：催化剂用量0.6%(相对于反应物的质量分数),酯醇摩尔比1.2：1,反应时间8h,反应温度125。按最佳反应条件进行酯交换反应,平均收率为96.2%。并将H836H2O应用于催化合成-甲基丙烯酸月桂醇酯的反应中,讨论酸醇的原料比、催化剂用量、带水剂、反应时间四个变化因素,制定4因素3水平正交试验方案L9(34),考察反应条件对酯化率的影响。通过实验条件和结果的综合比较从而得出H836H2O通过酯化法催化合成-甲基丙烯酸月桂醇酯的最佳反应条件为：月桂醇与a-甲基丙烯酸的物质的量比为1.3：1,催化剂的质量分数为0.4%(相对于反应物的质量分数),带水剂为10mL,反应时间2h。在最佳反应条件下,酯转化率近80%。【英文摘要】Heteropoly compounds are polynucler complexes with oxygen bridge, because they have unique molecular structure and they are easy to design and assemble, now it has widely used in new and efficient catalyst, Medicine, magnetic materials, high-quality sub-conductors, electrochromic materials, inorganic filler additives, selective electrode and fuel cell etc.This paper is to determine the inhibition effects of vanadium substituted heteropoly acid(W, P). Four novel vanadium atom substituted series of Dawson-type heteropoly acid (W, P) H7P2W17VO6230H2O (marked Dawson-V1), H8P2O6214H2O (marked Dawson-V2), H9P2W15V3O6224H2O (marked Dawson-V3) and H10P2W14V4 O6236H2O (marked Dawson-V4) and three novel vanadium atom substituted series of Keggin-type heteropoly acid (W, P) H4PW11V04015H20 (marked Keggin-V1),H5PW 10V2O4023H2O(marked Keggin-V2), H6PW9V3O4024H2O (marked Keggin-V3) were prepared by joining the raw materials step by step, acidificating step by step, circumfluencing, boiling and extracting with diethyl ether. Their structure were determined by IR, XRD, TG.The inhibition effects of vanadium substituted Dawson-type and Keggin-type heteropoly acid (W, P) were measured by differential scanning calorimetry (DSC). The results show that the polymerization velocity of MMA decreases continuously as the amount of the heteropoly acids in the same series and the polymerization velocity decreases continuously as the increasing of vanadium atomic number in the different series heteropoly acids, i.e. the greater vanadium atom number in the heteropoly acid, the better inhibition effect of heteropoly acid. On the whole, the inhibition effects of Dawson-type heteropoly acid are better than Keggin-type heteropoly acid.In the basis of the above experiment, H8P2W14V4O62H236H2O is identified as a catalyst to synthesze a-alcohol methacrylate esters. The influence of four factors of catalyst concentration、reaction temperature、molar ration of alcohol to ester and reaction time on the esterification rate was discussed by developing orthogonal pilot program Lg(34). The optimum conditions which determined by orthogonal experiment were as follows:the molar ration of-Methyl methacrylate to n-butanol was 1.2:1, weight of heteropolyacid was 0.6% of total weight, reaction time was 8h, reaction temperature was 125. Under the optimum conditions, the yield was about 96.2%. H8P2W14V4O62H236H2O is also applized to catalyze the esterification between dodecanol and methacrylic acid. The influence of four factors of catalyst concentration、reaction time、molar ration of alcohol to acid and the volume of toluene on the esterification rate is discussed by developing orthogonal pilot program L9(34). The results show the best reaction conditions are that dodecanol and methacrylic acid molar ratio is 1.3:1, the mass fraction of catalyst is 0.4%, the volume of toluene is 10mL and reaction time is 2h. Under the optimum conditions, the yield was about 80%.【关键词】磷钨钒杂多酸 Keggin型 Dawson型 阻聚性能 不饱和酯【英文关键词】heteropoly acid Dawson-type Keggin-type inhibition unsaturated Esters【目录】磷钨钒杂多酸阻聚性能及应用研究摘要4-5Abstract5-61 绪论9-271.1 多金属氧酸(盐)概述9-131.1.1 多酸化合物的结构10-121.1.2 多酸化合物的制备12-131.2 多酸化合物的功能和应用13-231.2.1 多酸化合物的催化化学13-151.2.2 多酸化合物的药物化学15-191.2.3 多酸超分子化合物的合成与非线性光学功能特性的研究19-201.2.4 固体杂多化合物的质子导电功能特性20-221.2.5 多阴离子的相转移化学221.2.6 电质变色与(EC)显示材料22-231.3 差示扫描量热法(DSC)综述23-251.3.1 差示扫描量热法(DSC)简介231.3.2 差示扫描量热法(DSC)原理23-241.3.3 影响DSC实验结构的因素24-251.4 国内外研究现状251.5 选题的理论意义和应用价值25-272 实验部分27-332.1 试剂与仪器27-282.2 多金属氧酸的合成28-302.2.1 Keggin型杂多酸H_4PW_(11)VO_(40)15H_2O(Keggin-V1)的合成28-292.2.2 Dawson型杂多酸H_7P_2W_(17)VO_(62)30H_2O(Dawson-V1)的合成29-302.3 多金属氧酸对甲基丙烯酸甲酯阻聚作用的测定302.4 多金属氧酸催化合成不饱和酯30-332.4.1 催化剂的选择302.4.2 H_8P_2W_(14)V_4O_(62)H_236H_2O催化甲基丙烯酸甲酯与正丁醇的酯交换应30-312.4.3 H_8P_2W_(14)V_4O_(62)H_236H_2O催化-甲基丙烯酸和月桂醇的酯化反应31-333 结果与讨论33-653.1 三种Keggin型磷钨钒杂多酸结构的表征33-363.1.1 Keggin型磷钨钒杂多酸的红外光谱分析333.1.2 Keggin型磷钨钒杂多酸的XRD分析33-353.1.3 Keggin型磷钨钒杂多酸的热重分析(TG)35-363.2 四种Dawson型磷钨钒杂多酸结构的表征36-423.2.1 Dawson型磷钨钒杂多酸的红外光谱分析36-373.2.2 Dawson型磷钨钒杂多酸的杂多酸的XRD分析37-393.2.3 Dawson型磷钨钒杂多酸的热重分析(TG)39-413.2.4 Dawson型磷钨钒杂多酸的合成条件讨论41-423.3 多金属氧酸对甲基丙烯酸