Exploiting block copolymer phase segregation to tune vitrimer properties

2019-12-19T11:17:25Z (GMT) by Jacob Ishibashi Yan Fang Julia Kalow

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In this paper, phase-segregating acrylic block copolymers are used to construct vitrimers. The resulting phase-segregated vitrimers display markedly different thermal and mechanical properties relative to those of homogeneous statistical copolymer-derived vitrimers. Importantly, the volume fraction of the functional block (i.e., the nominal cross-link density) can be used to modulate the stress relaxation profile of block vitrimers, while statistical copolymer-derived vitrimers display no change in relaxation behavior as a function of cross-link density. This study demonstrates that block copolymers offer additional design space to tune vitrimer properties, independent of polymer and cross-link identity and dynamic exchange chemistry.