Herein, we demonstrate the synthesis of a well-defined diblock copolymer consisting of isotactic polystyrene (iPS) and linear polyethylene, isotactic polystyrene-block-polyethylene (iPS-b-PE), by the combination o...Herein, we demonstrate the synthesis of a well-defined diblock copolymer consisting of isotactic polystyrene (iPS) and linear polyethylene, isotactic polystyrene-block-polyethylene (iPS-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 tempera^xre to provide highly isotactic polystyrene (iPS) and 1,4-trans-polybutadiene (1,4-trans-PBD) with narrow molecular weight distribution. Furthermore, the iPS-b-I,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 RuC12(PPh3)3 used as a catalyst to produce iPS-b-PE.展开更多
Herein we demonstrate crystallization-driven self-assembly ofisotactic polystyrene (iPS) with high isotacticity and narrow molecular weight distribution and crystallization-induced switching of the morphology of iPS...Herein we demonstrate crystallization-driven self-assembly ofisotactic polystyrene (iPS) with high isotacticity and narrow molecular weight distribution and crystallization-induced switching of the morphology of iPS aggregates in N, N-dimethylformamide (DMF). The formation and morphology switching of the self-assembled aggregates of iPS are investigated by means of dynamic light scattering (DLS), scanning electron microscopy (SEM), differential scanning calorimetry (DSC) and wide angle X-ray diffraction (WXRD). The results reveal that cooling DMF solution of iPS promotes iPS chains to self-assemble into spherical aggregates with a gelled core cross-linked by microcrystals, which is surrounded by solvent-swollen corona. Furthermore, crystallization induces the deformation of iPS aggregates from spherical to plate-like or nest-like.展开更多
基金supported by the National Natural Science Foundation of China(Nos.21174167 and51573212)the Natural Science Foundation of Guangdong Province(Nos.S2013030013474 and 2014A030313178)
文摘Herein, we demonstrate the synthesis of a well-defined diblock copolymer consisting of isotactic polystyrene (iPS) and linear polyethylene, isotactic polystyrene-block-polyethylene (iPS-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 tempera^xre to provide highly isotactic polystyrene (iPS) and 1,4-trans-polybutadiene (1,4-trans-PBD) with narrow molecular weight distribution. Furthermore, the iPS-b-I,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 RuC12(PPh3)3 used as a catalyst to produce iPS-b-PE.
基金financially supported by the National Natural Science Foundation of China(Nos.21174167 and 20974123)the Guangdong Province Higher School Science and Technology Innovation Key Project and the Natural Science Foundation of Guangdong Province(No.S2013030013474)
文摘Herein we demonstrate crystallization-driven self-assembly ofisotactic polystyrene (iPS) with high isotacticity and narrow molecular weight distribution and crystallization-induced switching of the morphology of iPS aggregates in N, N-dimethylformamide (DMF). The formation and morphology switching of the self-assembled aggregates of iPS are investigated by means of dynamic light scattering (DLS), scanning electron microscopy (SEM), differential scanning calorimetry (DSC) and wide angle X-ray diffraction (WXRD). The results reveal that cooling DMF solution of iPS promotes iPS chains to self-assemble into spherical aggregates with a gelled core cross-linked by microcrystals, which is surrounded by solvent-swollen corona. Furthermore, crystallization induces the deformation of iPS aggregates from spherical to plate-like or nest-like.