Titanasilsesquioxane-Alkylaluminum Catalyst System for Ethylene Polymerization

• 作者: Akshay Mehta Girish Mehta Gopal Tembe Parimal Parikh
• 来源期刊: 催化剂现代研究(英文)
• 学科: 化学
• 关键词: POSS Titanasilsesquioxane POLYETHYLENE Ethylaluminum Sesquichloride POLYMER MICROSTRUCTURE
• 年，卷（期）: 2012,（3）
• 页码范围: 29-42
• 页数: 14页
• 分类号: O6

摘要

Homogeneous Ti(IV) complexes covalently anchored to Polyhedral Oligomeric Silsesquioxane (POSS) have been synthesized by the stoichiometric reaction between titanium(IV)alkoxide and (iso-Octyl)7Si7O9(OH)3. These catalyst precursors formulated as [Ti(OR)(iso-Octyl)7Si7O12] were characterized by physicochemical and spectroscopic methods. These supported catalysts are found to be active in polymerization of ethylene at high temperatures in presence of ethylaluminum sesquichloride (Et3Al2Cl3, EASC) as co-catalyst. The polyethylene obtained are generally linear, crystalline and display low molecular weight distribution. The microstructure of the polymer was analyzed by NMR and FT-IR spectroscopic methods which indicated a chain transfer reaction to aluminum. The unique molecular properties of PE formed has been compared with commercial micronized PE wax which find industrial applications in surface coating and ink formulations. The effect of reaction conditions on catalytic behaviour is described.