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Role of High‐Molecular‐Weight Homopolymers on Block Copolymer Self‐Assembly: From Morphology Modifier to Template
Author(s) -
Zhang Shuo,
Cai Chunhua,
Xu Zhanwen,
Lin Jiaping,
Jin Xiao
Publication year - 2019
Publication title -
macromolecular chemistry and physics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.57
H-Index - 112
eISSN - 1521-3935
pISSN - 1022-1352
DOI - 10.1002/macp.201800443
Subject(s) - copolymer , micelle , ethylene glycol , polystyrene , polymer chemistry , polymer , self assembly , morphology (biology) , materials science , chemical engineering , peg ratio , vesicle , chemistry , nanotechnology , membrane , organic chemistry , aqueous solution , composite material , finance , biology , engineering , economics , genetics , biochemistry
For block copolymer (BCP)/homopolymer self‐assembly systems, the molecular weight of homopolymers is usually lower than that of BCPs. Herein, the cooperative self‐assembly of polystyrene‐ b ‐poly(ethylene glycol) (PS‐ b ‐PEG) BCPs with high‐molecular‐weight polystyrene (PS) homopolymers is reported. The molecular weight of PS homopolymers is 3–63 times that of the PS blocks. Typically, a spherical micelle–vesicle–large sphere morphology transition is observed by increasing the weight fraction of PS homopolymers in the polymer mixtures ( f HP ). Dynamic process studies reveal that with adding water to the solution of polymer mixtures in organic solvent, the homopolymers first collapse into globules, and their size increases with f HP and the molecular weight. Then these PS globules cooperatively self‐assemble with the PS‐ b ‐PEG BCPs. Depending on their size, these PS globules play different roles in the self‐assembly process. Small PS globules act as morphology modifiers inducing the micelle–vesicle transition, while large PS globules serve as self‐assembly templates for PS‐ b ‐PEG resulting in large spheres.