摘要
The copolymerization of 4-vinylbenzyl chloride （VBC） and vinyl acetate （VAC） was carried out in toluene at 75℃ via radical polymerization using 2,2＇-azo-bis-（isobutyronitrile） （AIBN） as an initiator. The random copolymers of poly（4-vinylbenzyl chloride-co-vinyl acetate） （P（VBC-co-VAC）） with number average molecular weight （Mn） from 2000 to 6900, relatively narrow molecular weight distribution （MWD, Mw/Mn ca. 2.0） and with different copolymer composition of 4-vinylbenzyl chloride （VBC） from 17 mol% to 62 mol% could be obtained. The P（VBC-co-VAC） copolymers with an average number of 7 to 13 initiating sites of benzyl chloride per macromolecule could be used for the cationic polymerization of isobutylene （IB）. The cationic polymerizations of IB were further conducted by using P（VBC-co-VAC） copolymers as macroinitiators in conjunction with TICl4 at -40℃ in CH2Cl2. The effects of VBC/TiCl4 （molar ratio） on monomer conversion, Mn and MWD of the resultant copolymers were investigated under 3 sets of conditions. It is found that P（VBC-co-VAC）-g-PIB copolymers with relatively narrow MWD （Mw/Mn ca. 2.0） and with terminal tert-chlorine functional groups in branched PIB chains could be successfully synthesized when VBC/TiCl4 （molar ratio） was set in the range from 0.10 to 1.12. The unimodal GPC curve of the P（VBC-co-VAC）-g-PIB copolymers by RI detector was almost in harmony with the GPC curve by UV detector. The TEM image of the P（VBC-co-VAC）-g-PIB copolymer stained by RuO indicated that the copolymer formed a two-phase morphology with P（VBC-co-VAC）-rich domains of 20-100 um in size tethered by PIB branch segments.
The copolymerization of 4-vinylbenzyl chloride （VBC） and vinyl acetate （VAC） was carried out in toluene at 75℃ via radical polymerization using 2,2＇-azo-bis-（isobutyronitrile） （AIBN） as an initiator. The random copolymers of poly（4-vinylbenzyl chloride-co-vinyl acetate） （P（VBC-co-VAC）） with number average molecular weight （Mn） from 2000 to 6900, relatively narrow molecular weight distribution （MWD, Mw/Mn ca. 2.0） and with different copolymer composition of 4-vinylbenzyl chloride （VBC） from 17 mol% to 62 mol% could be obtained. The P（VBC-co-VAC） copolymers with an average number of 7 to 13 initiating sites of benzyl chloride per macromolecule could be used for the cationic polymerization of isobutylene （IB）. The cationic polymerizations of IB were further conducted by using P（VBC-co-VAC） copolymers as macroinitiators in conjunction with TICl4 at -40℃ in CH2Cl2. The effects of VBC/TiCl4 （molar ratio） on monomer conversion, Mn and MWD of the resultant copolymers were investigated under 3 sets of conditions. It is found that P（VBC-co-VAC）-g-PIB copolymers with relatively narrow MWD （Mw/Mn ca. 2.0） and with terminal tert-chlorine functional groups in branched PIB chains could be successfully synthesized when VBC/TiCl4 （molar ratio） was set in the range from 0.10 to 1.12. The unimodal GPC curve of the P（VBC-co-VAC）-g-PIB copolymers by RI detector was almost in harmony with the GPC curve by UV detector. The TEM image of the P（VBC-co-VAC）-g-PIB copolymer stained by RuO indicated that the copolymer formed a two-phase morphology with P（VBC-co-VAC）-rich domains of 20-100 um in size tethered by PIB branch segments.
基金
supported by the National Natural Science Foundation of China(Nos.20774008,20934001)
Program for Changjiang Scholars and Innovative Research Team in Universities(IRT0706)
