Synthesis and Bulk Self-Assembly of Well-Defined Binary Graft Copolymers

Abstract

Six binary graft copolymers were synthesized, and their graft segregation in bulk was investigated. The copolymers were prepared by a one-pot method involving the quantitative grafting of alkyne-end-functionalized poly(n-butyl acrylate) (PBA-C≡CH) and poly(2-cinnamoyloxyethyl methacrylate) (PCEMA-C≡CH) onto poly(3-azide-2-hydroxypropyl methacrylate) (P(GMA-N3)) via click chemistry. Of these copolymers, three had a total PBA and PCEMA molar grafting density g of ∼20%, and their PBA volume fractions VB among PBA and PCEMA varied between 28% and 57%. VB was constant at ∼57%, while g varied between 9.8% and 29.5% for the other three samples. Bulk films were obtained by slowly evaporating the solvent from cast solutions of these copolymers. These films were then annealed above the glass transition temperatures of PBA and PCEMA to facilitate graft segregation. The graft segregation patterns were examined by performing transmission electron microscopy (TEM) analysis of thin sections of these films. The TEM resul...