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Abstract: Gold nanoparticles “AuNPs” with improved stability against aggregation were prepared using a self-assembled ABC non-amphiphilic poly(dimethylsiloxane)-b-poly(methyl methacrylate)-b-poly(2,2,3,3,4,4,4-heptafluorobutylmethacrylate) (PDMS-b-PMMA-b-PHFBMA) triblock copolymer as a template. The polymer-stabilized AuNPs were characterized by UV–visible spectrophotometry and transmission electron microscopy (TEM). Depending on the self-assembled templates, the relatively monodispersed and stable AuNPs with an average diameter of 30 nm were obtained. Therefore the triblock copolymer was demonstrated to be an effective stabilizer for the synthesis of AuNPs. The PDMS-b-PMMA-b-PHFBMA copolymer used in the study contains siloxane and fluorinated segments and belongs to ABC non-amphiphilic triblock copolymers, which proves that the asymmetric ABC non-amphiphilic triblock copolymers can also self-assemble in a dilute solution to serve as a template, or “nanoreactors”. To the best of our knowledge, this work is the first example of facile preparation of metal nanoparticles using self-assembled ABC non-amphiphilic fluorosilicone triblock copolymer as a template. Our present work broadens the range of polymer templates that can be used to synthesize and stabilize metal nanoparticles from amphiphilic block polymers (or symmetric ABA non-amphiphilic block polymers) to asymmetric ABC non-amphiphilic block polymers. In addition, this work also broadens the application of fluorinated ABC triblock copolymers. [Copyright &y& Elsevier]

Abstract: Well-defined poly(dimethylsiloxane)-b-poly(2,2,3,3,4,4,4-heptafluorobutyl methacrylate-b-poly(styrene) (PDMS-b-PHFBMA-b-PS) triblock copolymers were prepared by two-step reversible addition-fragmentation chain transfer (RAFT) polymerization. The two-step RAFT polymerization proceeded in a controlled manner as demonstrated by the macromolecular characteristics of the blocks and corresponding polymerization kinetic data. Furthermore, surface properties and morphologies of the polymers were investigated with static water contact angle (WCA) measurement, X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM) and atomic force microscopy (AFM) which showed low surface energy and microphase-separation surfaces. [Copyright &y& Elsevier]