Synthesis Of CO₂/PO/VCHO Terpolymers And Theirs Modification

Whether from an environmental or economic point of view,copolymerization of epoxides and carbon dioxide?CO₂?to prepare biodegradable polycarbonates has been regarded as the most promising green polymerization process.Since the pioneering work reported by Inoue in the late 1960s,both in the development of efficient catalytic system or in the improvement of polymerization technology have made considerable progress.But the further development of this green technology is suffering from material performance and product type etc.Therefore,the synthesis of more diverse polycarbonate to improve material performances and categories of this greener polymer is an important and challenging topic for research and development.In terms of the above problems,we devoted efforts on synthesis of new biodegradable polycarbonates based on 4-vinyl-cyclohexene-1,2-epoxide?VCHO?,propylene oxide?PO?and CO₂ using our superior functional SalenCo???NO₃ catalyst and studied postmodification of the vinyl groups in the resultant terpolymers.In addition,based on the understanding of functional SalenCo???X complexes,the synthesis of eugenol derivatives and brominated hydrocarbons was discussed.The main contents were summaried as follows:1.The influences of various reaction conditions such as molar ratio of the monomers,reaction time and reaction temperature on the terpolymerization of CO₂/PO/VCHO catalyzed by SalenCo???NO₃ complex were investigated.The resulting terpolymers showed only one thermolysis peak and one adjustable T_g dependable on vinyl cyclohexene carbonate?VCHC?unit content with the relationship of“T_g?^oC?=64*F_Vinyl+39”.2.The epoxy group?EP?was incorporated by oxidation of vinyl group of VCHC units and the cyclic carbonate?CC?group was achieved by reaction of CO₂ with epoxy-functionalized terpolymer.The linear dependencies of the T_g on the mole fractions ratio of EP and CC groups on the poly?cyclohexene carbonate??PCHC?main chain were also observed.Notably,the T_g of fully CC-functionalized PCHC was up to 196 ^oC,which was the highest T_g of CO₂-based polycarbonate reported at the absence of cross-linked structure.In addition,the effects of concentration,time,initiator on the thiol-ene reaction of vinyl group of VCHC units with mercaptan were investigated.3.A series of eugenol derivatives were prepared by hydroboration,halogenation and so on,and synthesis of various benzyl-bromide derivatives using three methods of hosphorus tribromide,hydrobromic acid,acetic acid solution of hydrobromic acid were discussed.