نتایج جستجو برای: natta polymerization
تعداد نتایج: 30540 فیلتر نتایج به سال:
Despite decades of extensive studies, the atomic-scale structure active sites in heterogeneous Ziegler–Natta (ZN) catalysts, one most important processes chemical industry, remains elusive and a matter debate. In present work, ZN catalysts absence ethylene, referred to as dormant sites, is elucidated from magnetic resonance experiments carried out on samples reacted with increasing amounts BCl3...
In a gas phase %uidized bed ole)n polymerization reactor, it is generally assumed that polymer particles are well mixed and near isothermal reaction conditions prevail. When a highly active Ziegler–Natta catalyst or other type of high activity supported catalyst is used in a gas phase %uidized bed reactor, a certain heterogeneity in the polymer properties is often observed in di4erent size part...
This theoretical study was inspired by the perpetual debate over the so-called "dormancy" of the active sites in propylene polymerization, i.e., a drop in their activity after a regioerror (2,1-insertion), which was reported to occur in many (although not all) catalytic systems. To explore the range of possible situations, we have selected two homogeneous systems of fundamentally different stru...
SiO2/MgCl2 (ethoxide type)/TiCl4 Ziegler-Natta catalysts for use in ethylene polymerization and ethylene/1-hexene copolymerization have been prepared using silica with a supported layer of magnesium ethoxide (Mg(OEt)2) as a catalyst precursor, followed by treating with TiCl4 at different Ti/Mg molar ratios, which showed significant effects on the active centers and pore structures of the cataly...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید