Multi-stimuli-triggered shape transformation of polymeric filaments derived from dynamic covalent block copolymers.

Multi-stimuli-triggered shape transformation of polymeric filaments derived from dynamic covalent block copolymers. Biomacromolecules. 2020 Sep 08;: Authors: Yang G, Wang J, Yan Y, Hai Z, Hua Z, Chen G Abstract Using dynamic polymers to achieve the morphology transformation of polymeric assemblies under different conditions is challenging. Herein, we reported diversiform shape transformations of multi-responsive polymer filaments, which were self-assembled by a new kind of amphiphilic block copolymers (PVEG-PVEA) possessing dynamic and reversible acylhydrazone bonds through re-acting of benzaldehyde-containing block copolymers poly(vinylbenzaldehyde)-b-poly(N-(4-vinylbenzyl)-N, N-diethylamine) (PVBA-PVEA) with acylhydrazine modified oligoethylene glycol. It was found that the resulting amphiphilic and dynamic PVEG-PVEA was capable of hierarchically self-assembling into intriguing core-branched filaments in aqueous solution. Notably, the features of acylhydrazone bonds and PVEA block endow the filaments with multi-responsiveness in-cluding acid, base and temperature, leading to the multiple morphological transformations under such stimuli. Moreover, the core-branched filaments would further transform into polymeric braided bundles driven by hydrogen bonding interactions of amide bonds. It is noteworthy that both of core-branched and braided bundles made from polymers are quite rare. These diversiform polymeric assemblies and their mor...
Source: Biomacromolecules - Category: Biochemistry Authors: Tags: Biomacromolecules Source Type: research