Synthesis and studies on self-assembly of photo-sensitive amphiphilic random copolymers

A Series of photo-sensitive macromonomers FA(n) C ( n = 1 similar to 4) were synthesized by using caprolactone-modified acrylates, FAn and cinnamyl choride, and copolymers PMFA(n)C were synthesized by free radical copolymerization of FA(n)C with MAA in DMF using 2, 2'-azobisisobutyronitrile as initiator. The structures of copolymers were characterized by using GPC, DSC, IR and H-1-MNR techniques. The copolymers form spherical micelles in aqueous solutions with PFA(n)C chains as the core, and PMAA chains as the corona. The stable nanospheres were prepared by photo-crosslinking of the cores of the micelles. These micelles were characterized by DLS and TEM. The results showed that PMFA(n)C could self-assemble into nanometer micelles with narrow size distribution, and the hydrodynamic radius R-h of the crosslinked micelles was smaller than that of the uncrosslinked ones. The critical aggregation concentratio of micelle formation and the R, value both decreased with increase of the n value of the copolymers.