Controlled Thioacyl Group Transfer(TAGT)Polymerization of Cyclic Sulfide:Novel Approach to AB Diblock Copolymers by the Combination of RAFT and TAGT Polymerizations

摘要

Polysulfides can be used in coatings,adhesives,sealants,and other applications,as they possess excellent thermal stability,weatherabihty,solvent resistance,and oil resistance.A possible method for the synthesis of polymonosulfides are certain reaction of dithiols with appropriate reagents,such as diolefins,dihalides,carboxyl compounds,and the reaction of dihalides with alkali metal sulfides,yielding A2B2 polymers.However,these types of step polymerization systems are not appropriate for synthesizing polysulfides with highly organized macro-molecular architectures with controlled molecular weight,narrow polydispersity,and precise topology(e.q.,block,graft,and star polymers).