甲基铝氧烷的合成

用含水硅胶作为三甲基铝的水解剂制备了甲基铝氧烷(MAO)，研究了影响MAO收率及聚合活性的因素，得到了合成MAO的最佳反应条件。结果表明，水／TMA(摩尔比)、三甲基铝的滴加时间、低温反应时间对MAO的收率及其聚合活性有直接影响，硅胶中水的质量分数对MAO反应收率有较明显的影响，而对MAO的聚合活性影响不大。合成MAO反应的最佳工艺条件是：水／三甲基铝(摩尔比)1．4，三甲基铝滴加时间lh，低温反应时间2h。在最佳工艺条件下，MAO的反应收率可达到49％。

Synthesis of methylaluminoxane

The methylaluminoxane(MAO)was synthesized by hydrolysis of trimethyl aluminum(TMA)with silica gel con-taining water.The factors influenced the yield and the poly-merizing activity of MAO were discussed.The optimum condi-tions were obtained.The results showed that the yield and the polymerizing activity were directly affected by H 2 O /TMA(molar ratio),time of TMA addition and reaction time at lower temperature,and mass fraction of wa ter in silica gel had obvi-ous effects on yield,but had no effec t on the polymerizing ac-tivity.The optimum conditions of sy nthesis of MAO were H 2 O /TMA(molar ratio)1.4,time of TMA addition 1h and reaction time 2h at lower temperature.The yie ld of 49%of this reac-tion could be attained under the abov e conditions.