Dynamic Origin and Thermally Induced Evolution of New Self-Assembled Aggregates from an Amphiphilic Comb-Like Graft Copolymer: A Multiscale and Multimorphological Procedure
作者：Gang Wu, Si-Chong Chen,* Xiu-Li Wang, Ke-Ke Yang, and Yu-Zhong Wang*
關(guān)鍵字：Crystallization induced self-assembly
論文來(lái)源：期刊
具體來(lái)源：Chemistry European Journal
發(fā)表時(shí)間：2012年
Considering the shape plays a crucial role in determining physical and chemical properties of aggregates,[13] the controlled fabrication and switch of morphologies have been paid a great attention, which has been implemented by regulating the conditions, such as solvent,[14] pH,[15] redox,[16] and so on. Typically, crystallization is an important factor utilized to control the self-assembly of semicrystalline block copolymers consisting of the crystallizable block and amorphous block, which has been actively researched recently.[17] Inspired by this specific class of copolymer, we have designed an amphiphilic comb-like graft copolymer consisting of poly(p-dioxanone) (PPDO) as a crystallizable hydrophobic side chain and poly(vinyl alcohol) (PVA) as a hydrophilic main chain,[18] and found that this copolymer presented an unique self-assembled behavior. In fact, recently we reported a “star anise”-like nanoaggregate from a PPDO-based branched alternating multi-block copolymer.[19] Herein, by directly dispersing this PPDO-based amphiphilic comb-like graft copolymer into water, more complex and regular aggregates with a well-defined snowflake-like superstructure was obtained, and their origin involving a dynamically disorder–order change from nano- to submicroscale was visualized. Moreover, the aggregates showed thermally induced multimorphological evolution from a snowflake-like to cluster- like structure. As an original and significant work, this superstructure enriches the self-assembled morphology of amphiphiles, especially comb-like macromolecules. Furthermore, the direct water phase self-assembled strategy of PPDO-based amphiphilic copolymers and temperature-adjusted morphological change could provide a new idea to construct complex multimorphological and multiscale objects.