کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
5191084 | 1381225 | 2005 | 8 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Physical transitions and nascent morphology of syndiotactic polystyrene in slurry polymerization with embedded Cp*Ti(OMe)3/methyl aluminoxane catalyst
دانلود مقاله + سفارش ترجمه
دانلود مقاله ISI انگلیسی
رایگان برای ایرانیان
کلمات کلیدی
موضوعات مرتبط
مهندسی و علوم پایه
شیمی
شیمی آلی
پیش نمایش صفحه اول مقاله
چکیده انگلیسی
The physical transitions and nascent morphology of syndiotactic polystyrene (sPS) synthesized over heterogeneized embedded Cp*Ti(OMe)3/MAO catalyst in n-heptane slurry polymerization have been investigated. The homogeneous metallocene catalyst is heterogenized by embedding active titanium sites into an sPS prepolymer phase. At low styrene concentrations, the reaction mixture is well-dispersed slurry of sPS particles and at high styrene concentrations, swollen sPS particles form aggregates that become a wet powder phase. For a wide range of styrene concentrations, no global gelation occurs with the embedded catalyst. Complex nascent morphology of sPS polymers is also presented. Scanning electron microscopic images show that spherical as well as irregular-shaped microparticles, films, and fibers are formed and that particle generation and growth mechanisms are different from that of heterogeneously catalyzed α-olefin polymerization processes.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Polymer - Volume 46, Issue 14, 27 June 2005, Pages 5032-5039
Journal: Polymer - Volume 46, Issue 14, 27 June 2005, Pages 5032-5039
نویسندگان
Hyung Woo Lee, Jin Suk Chung, Kyu Yong Choi,