聚烯烃催化剂载体硅胶活化条件的研究

Thermal activation conditions of silica gel carrier for catalysts of olefin polymerization

研究了不同活化条件对聚烯烃催化剂载体硅胶的灼烧失重、表面形态、孔容以及催化剂的活性、聚合物形态的影响。实验结果表明:对聚烯烃催化剂载体硅胶表面特性的调控可通过改变热活化条件实现;热活化条件的选择直接影响载体硅胶所制备催化剂的性能及生成的聚合物形态;载体硅胶热活化时,发生孔容变化的起始温度为600℃;聚烯烃催化剂载体硅胶的最佳热活化条件是200℃(1h)→400℃(1h)→600℃(2h)和200℃(2h)→600℃(4h)的梯度温度下的二次活化。

The influences were studied of different thermal activation conditions on the calcination loss, superficial morphology,pore volume of silica gel carriers, the activity of catalysts supported by silica gel and polymer morphology. The results show that the surface characteristics of silica gel carrier can be controlled by altering thermal activation conditions. And the selection of thermal activation conditions can directly influence on the performances of supported catalysts of olefin polymerization and the morphology of polymer polymerized by polyolefin catalysts. And the temperature of the initial variation of pore volume is at 600 ℃. The optimum thermal activation condition of silica gel carrier for catalysts of olefin polymerization is as follows： at 200 ℃ （1 h）→400℃ （1 h）→600℃ （2 h） and at 200 ℃ （2 h）→300 ℃ （4 h） for two thermal activations.