Abstract：In order to produce broad/bimodal molecular weight polyethylene in a single reactor, strengthen the ethylene polymerization process, to reduce the investment in production and energy consumption, and achieve the molecular scale mixing in situ chemical synthesis, a diffusion/barrier composite support was prepared to regulate and control properties of polyethylene. Based on phase inversion principle, spherical and well-dispersed polymer-coated particles (SiO2/PSA) were successfully prepared using silica (SiO2) and poly[styrene-co-(acrylic acid)] (PSA). Then we successfully prepared supported hybrid catalysts with different catalyst divided by PSA layer. With ethylene, hydrogen and α-olefin diffuse differently in the PSA layer, and active components such as Cp2ZrCl2, TiCl3 and TiCl4 behave differently in dynamic, we construct two micro-chemical environment, inside and outside of the PSA layer, so that active component prepares low Mw, low branched polymer chains and high Mw, high branched polymer chains separately in different micro-chemical environment. Meanwhile, we could regulate the active component and the thickness of PSA layer to control the molecular weight distribution of polyethylene.
Yang Yong,Li Wei,Du Lijun et al. Control of Diffusion/Barrier Effects of Polymer-Coated Particles and the Strengthening of Ethylene Polymerization Reactor[J]. 化学反应工程与工艺, 2013, 29(3): 260-268.
