Synthesis of isotactic polystyrene-block-polyethylene by the combination of sequential monomer addition and hydrogenation of 1,4-trans-polybutadiene block
Herein, we demonstrate the synthesis of a well-defined diblock copolymer consisting of isotactic polystyrene ( i PS) and linear polyethylene, isotactic polystyrene-block-polyethylene ( i PS- b -PE), by the combination of sequential monomer addition and hydrogenation. Isospecific living polymerization of styrene and living trans -1,4-polymerization of 1,3-butadiene were catalyzed by 1,4-dithiabutandiyl-2,2′-bis(6-cumenyl-4-methylphenoxy) titanium dichloride (complex 1) activated by triisobutyl aluminum modified methylaluminoxane (MMAO) at room temperature to provide highly isotactic polystyrene ( i PS) and 1,4- trans -polybutadiene (1,4- trans -PBD) with narrow molecular weight distribution. Furthermore, the iPS-b-1,4- trans -PBD was synthesized via sequential monomer addition in the presence of complex 1 and MMAO. The hydrogenation of the 1,4- trans -PBD block was promoted by RuCl 2 (PPh 3 ) 3 used as a catalyst to produce i PS- b -PE.
危险品化学品经营许可证（带存储）