Precise Tailoring of Polyester Bottlebrush Amphiphiles toward Eco‐Friendly Photonic Pigments via Interfacial Self‐Assembly. (11th July 2022) - Guo, Qilin
Abstract: Biodegradable photonic microspheres with structural colors are promising substitutes to polluting microbeads and toxic dyes. Here, amphiphilic polyester‐ block ‐poly(ethylene glycol) bottlebrush block copolymers (BBCPs) with polylactic acid or poly(ϵ‐caprolactone) as the hydrophobic block are synthesized and used to fabricate eco‐friendly photonic pigments. Molecular parameters of BBCPs, including rigidity and symmetry, are precisely tailored by variation of side chain lengths, which enables effective manipulation of interfacial tension ( γ ). Organized spontaneous emulsion mechanism is enabled only when γ falls in a suitable range (10.6–14.3 mN m −1 ), producing ordered water‐in‐oil‐in‐water multiple emulsions and ordered porous structures. Consequently, highly saturated and tunable structural colors are observed due to coherent light scattering from the porous structures. Such photonic materials are nontoxic as confirmed by careful safety tests using aquatic model organisms. Abstract : Polyester‐ block ‐poly(ethylene glycol) bottlebrush block copolymers with varied side chain lengths are utilized for the fabrication of biodegradable photonic microspheres. The eco‐friendly photonic pigments with highly saturated structural colors can be the ideal substitutes to nondegradable microbeads and toxic pigments, providing a new strategy to reduce the micro‐polluting items and toxic chemicals in our ecosystem.