关键词: FONT-SIZE: 10.5pt, mso-bidi-font-size: 11.0pt, mso-bidi-font-family: 宋体, mso-font-kerning: 1.0pt, mso-ansi-language: EN-US, mso-fareast-language: ZH-CN, mso-bidi-language: AR-SA, mso-fareast-font-family: 宋体, mso-hansi-font-family: 宋体" lang=EN-US>Ziegler-Natta FONT-SIZE: 10.5pt, mso-bidi-font-size: 11.0pt, mso-ascii-font-family: Calibri, mso-bidi-font-family: 宋体, mso-font-kerning: 1.0pt, mso-ansi-language: EN-US, mso-fareast-language: ZH-CN, mso-bidi-language: AR-SA">催化剂复合载体乙烯聚合

Abstract:

SiO₂/MgCl₂·xBu(OH)₂/poly(styrene-co-acrylic acid) inorganic/organic hybrid support was synthesized and was of three types of chemical environments: inorganic support SiO₂, MgCl₂·xBu(OH)₂  adduct and organic support PSA.TiCl₄ was immobilized on the hybrid support.The influences of its composition on the titanium content, catalyst morphology and performance in ethylene polymerizations were also investigated.The results showed that titanium content decreased sharply when PSA was added to the hybrid support.The kinetic study of ethylene/1-hexene copolymerization indicated that there was a long period of diffusion-controlled induction time at the initial stage for the hybrid catalysts, due to the barrier effect from PSA, comparing with SiO₂/MgCl₂·xBu(OH)₂/TiCl₄ that had no induction time in ethylene polymerization. As the content of PSA increased, the induction time extended and almost no decay happened until the end of the polymerization.Moreover, the polyethylene produced by SiO₂/MgCl₂·xBu(OH)₂/PSA/TiCl₄ was of broader molecular weight distribution(MWD) and high melt flow ratio. Based on its morphological features showed by SEM, the polymerization mechanism of the hybrid catalysts was also investigated.

Key words: FONT-SIZE: 10.5pt, mso-bidi-font-size: 11.0pt, mso-bidi-font-family: 宋体, mso-font-kerning: 1.0pt, mso-ansi-language: EN-US, mso-fareast-language: ZH-CN, mso-bidi-language: AR-SA, mso-fareast-font-family: 宋体, mso-hansi-font-family: 宋体" lang=EN-US>Ziegler-Natta FONT-SIZE: 10.5pt, mso-bidi-font-size: 11.0pt, mso-ascii-font-family: Calibri, mso-bidi-font-family: 宋体, mso-font-kerning: 1.0pt, mso-ansi-language: EN-US, mso-fareast-language: ZH-CN, mso-bidi-language: AR-SA">催化剂复合载体乙烯聚合