Dynamic Polypyrrole Core–Shell Chemomechanical Actuators

• DOI: 10.1021/acs.chemmater.1c03896
• Publication Date: 2022-03-22T18:33:20Z
• Authors: Weize Yuan; Harikrishnan Vija...; Shao-Xiong Lennon...; Keith Husted; Jeremiah A. Johnson; Timothy M. Swager
• Keywords: Polypyrrole; Particle (ecology); Emulsion polymerization; Interfacial polymerization

Conducting polymer fabricated oil-in-water (o/w) colloidal particles were developed via a single step of in situ interfacial polymerization an emulsion phase, exhibiting unique core–shell structure, where the shell was governed by thin layer polypyrrole (pPy) film at o/w interface. These afford dynamic actuating shapes and configurations when pPy interface is chemically oxidized into charged state or, alternatively, it reduced noncharged state. Mechanisms particles' volumetric expansion rely on repulsive interaction resulting from positively as well insertion negatively oxidant species. Notably, these demonstrated ability to expand up 400% their initial dimensions while retaining structures can shrink back original size. Electrochemical actuation tests also display similar structural changes those obtained using chemical actuation. Measuring size triggered inside different poly(ethylene glycol) (PEG) gels allows for evaluation forces generated particle interfaces. Organic dyes compatible with could be trapped within interior demonstrating prospects including functionalities this material system.