Formation of biomimetic hierarchical nanostructure in homopolymers and block copolymer ternary blend particles

• 作者: Shu Kikuchi Ryoka Shoji Shinji Kanehashi Guanghui Ma Kenji Ogino
• 来源期刊: 颗粒学报（英文版）
• 年，卷（期）: 2022,（5）
• 所属期刊栏目: Special Issue Natural and Biomimetic Particles in Bio-applications
• 页码范围: 98-109
• 页数: 12页
• 语种: 英文

摘要

In order to mimic hierarchical nanostructures in nature,particles of polymer blends consisting of poly(4-butyltriphenylamine) (PBTPA),poly(methyl methacrylate) (PMMA) and PBTPA-block-PMMA were fabricated by a solvent evaporation method.Effects of the molecular weight and the chemical composi-tion of PBTPA-b-PMMA,molecular weights of homopolymers,and the composition of the blend on the morphology were investigated.The polymer blend particle consisting of PBTPA and PMMA homopoly-mers exhibited thermodynamically favored core-shell structure,in which more hydrophilic PMMA-shell surrounded PBTPA-core.The addition of 10 wt％ of PBTPA-b-PMMA caused the morphological transition from core-shell toJanus or inversed core-shell,in which PBTPA-shell surrounded PMMA-core,depending on the molecular weight of PBTPA segment in PBTPA-b-PMMA.When the molecular weight of PMMA segment was higher than that of PMMA homopolymer,watermelon-like particles in which small PBTPA domain less than 80 nm dispersed in the PMMA domain surrounded by PBTPA shell were observed.As the ratio of PBTPA-b-PMMA increased,the interface of the macrophase separation became obscure.At 50 wt％ of the PBTPA-b-PMMA,only microphase separation was observed.The measurement of interfa-cial tension by pendant drop method demonstrated that PBTPA-b-PMMA lower the interfacial tension between PBTPA and the aqueous phase to the value similar to that of PMMA with the aqueous phase.