Shape memory polymers(SMPs)are promising functional materials which have drawn a great deal of research interest in recent years.Yet the application of SMPs has been limited by their low strength compared to other shape memory materials.Nanofillers such as clay,carbon materials and silica have been employed to reinforce SMPs.The fabrications of such SMP composites usually include dispersion of nanofillers in prepolymers and subsequent curing with crosslinking agents.Homogeneous dispersion of nanofillers in polymer matrix,which is essential to effective reinforcement,is often hard to achieve in these processes.In our recent work,a copolymer of styrene and 3-Isopropenyl-α,α-dimethylbenzyl isocyanate(P(St-co-TMI))was synthesized via free radical polymerization and then crosslinked with graphene oxide(GO)via solution mixing.The isocyanate groups could react with oxygen-containing groups of GO and serve as crosslinking sites.It has been found that GO was well dispersed in polymer matix and played the roles of macro-crosslinker and reinforcement nanofiller at the same time.The resultant composite exhibited good mechanical properties and heat-induced shape memory behavior.Thus we have presented a facile method to effectively incorporate GO into polymer matrix as reinforcing macro-crosslinker,which could be adapted to the fabrication of other elastomer composites.