论文部分内容阅读
将磷钨酸原位包埋在SiO2的三维网络中,制备得到SiO2负载磷钨酸催化剂(PW12/SiO2);在该催化剂作用下以甲氧基聚乙二醇和甲基丙烯酸为原料合成了甲氧基聚乙二醇甲基丙烯酸酯;通过正交实验确定了优化条件:n(AA)/n(PEG)=3,催化剂质量分数为1%(以醇酸总质量计),阻聚剂质量分数1%(以醇酸总质量计),酯化时间10 h,在该条件下,酯化率达93.6%,产率为83.46%。在高负载量下,磷钨酸在载体上仍然高度分散且没有晶相堆积,反应中催化剂活性组分溶脱量少,催化剂重复使用6次,催化活性未明显降低。
Phosphotungstic acid was entrapped in the three-dimensional network of SiO2 in situ to prepare the SiO2-loaded phosphotungstic acid catalyst (PW12 / SiO2). Under the action of the catalyst, methoxypolyethylene glycol and methacrylic acid were used as raw materials to synthesize a The optimal conditions were n (AA) / n (PEG) = 3, the mass fraction of catalyst was 1% (based on the total mass of alkyd), the polymerization inhibitor The mass fraction of 1% (based on the total alkalinity), esterification time 10 h, under the conditions, the esterification rate of 93.6%, the yield was 83.46%. At high loadings, phosphotungstic acid is still highly dispersed on the support without any phase accumulation. The amount of catalyst active component eluted is small and the catalyst is reused 6 times without any significant decrease in catalytic activity.