新型聚合物载体茂金属催化剂

均相茂金属催化剂虽然有许多优点和特点,但也存在着某些不足之处，例如，不适于现在通用的气相和淤浆聚合工艺；要想达到足够的聚合活性需大量价格昂贵的MAO；相当多的均相茂金属催化剂不适于高温聚合（活性降低，分子极低），不能很好地控制聚合物的形态，为了在工业上得到实际应用，必须将它们载体（非均相）化。通常采用的载体都是无机物，如SiO2、MgCl2、Al2O3等。由于无机载体表面具有酸性，负载茂金属催化剂活性有所降低，用聚合和作茂金属催化剂的载体很少有报道，我们研制了一种新型的聚合物载体茂金属催化剂，即可保持均相茂金属催化特点和优点，又能克服其缺点。其合成路线如下。

A Novel Type ofPolymer-Supported Metallocene Catalyst for Ethylene Polymerization

A novel polymer-supported metallocene catalyst has been prepared. The polymer-support-ed metallocene displayed considerably high activity in ethylene polymerization, the highest being 3.62× 107 g/(mol · h), the molecular weight of the polyethylene produced was Mn = 1.29 × 105 , about 3～4 times those prepared by corresponding homogeneous zirconocenes. The polymer-supported metallocene poly(styrene-acrylamide)supported zirconocene]keeps thecharacteristics of homogeneous metallocene catalysts, and offers some features, such as adaptable togas phase and slurry processes; easy to prepare in low cost; relatively high activity and lowerMAO/Zr ratio ; lower inorganic residues in the polyolefins as compared to those using SiO2, Al2O3 orMgCl2; unitary active structure, no complex surface as with SiO2; good control of morphology of theresulting polymer.