The Origin of Hierarchical Structure Formation in Highly Grafted Symmetric Supramolecular Double-Comb Diblock Copolymers

4 years ago

The Origin of Hierarchical Structure Formation in Highly Grafted Symmetric Supramolecular Double-Comb Diblock Copolymers

Mehedi Reza, Gerrit ten Brinke, Anton H. Hofman, Katja Loos, Janne Ruokolainen

Involving supramolecular chemistry in self-assembling block copolymer systems enables design of complex macromolecular architectures that, in turn, could lead to complex phase behavior. It is an elegant route, as complicated and sensitive synthesis techniques can be avoided. Highly grafted double-comb diblock copolymers based on symmetric double hydrogen bond accepting poly(4-vinylpyridine)-block-poly(N-acryloylpiperidine) diblock copolymers and donating 3-nonadecylphenol amphiphiles are realized and studied systematically by changing the molecular weight of the copolymer. Double perpendicular lamellae-in-lamellae are formed in all complexes, independent of the copolymer molecular weight. Temperature-resolved measurements demonstrate that the supramolecular nature and ability to crystallize are responsible for the formation of such multiblock-like structures. Because of these driving forces and severe plasticization of the complexes in the liquid crystalline state, this supramolecular approach can be useful for steering self-assembly of both low- and high-molecular-weight block copolymer systems. Given the low concentration of copolymer, it is surprising to see that symmetric and highly grafted supramolecular double-comb diblock copolymers can self-assemble into ordered hierarchical morphologies. Multiple phase transitions are responsible for such behavior, and enable this supramolecular approach to be applicable in both low- and high-molecular-weight systems.

Publisher URL: http://onlinelibrary.wiley.com/resolve/doi

DOI: 10.1002/marc.201700288