Topochemical polymerization of hierarchically ordered diacetylene monomers within the block copolymer domains

Abstract

Integration of polymerizable small molecules within block copolymer based supramolecules provides a new strategy to generate functional materials. Herein we report hydrogen-bonding complexes of photopolymerizable 10,12-pentacosadyionic acid (PCDA) and polystyrene-block-poly(4-vinylpyridine) (PS-b-P4VP). We systematically investigate how annealing conditions affect the hierarchical ordering and the molecular orientation of PCDA molecules within the block copolymer microdomains and subsequently the topochemical polymerization of PCDA. It was found that solvent vapor annealing is a more appropriate method to obtain the desired molecular orientation of PCDA for an effective topochemical polymerization compared to the thermal annealing method. The hierarchical ordering of the block copolymer supramolecules upon UV irradiation and melt-cooling was investigated at multiple length scales by a combination of different techniques including small-angle X-ray scattering and wide-angle X-ray scattering.