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Summary: We report for the first time the synthesis of unimolecular polystyrene-based nanoparticles (PS-NPs) under normal air atmosphere by direct carbon-carbon 'click' chemistry ( i.e., 'self-click' chemistry). First, statistical poly(styrene- co-4-vinylbenzyl chloride) copolymers synthesized by RAFT polymerization were decorated in a facile manner with alkyne groups by reaction with potassium propiolate, providing well-defined nanoparticle precursors (PS-Prec). Next, individual PS-Prec chains were collapsed irreversibly to unimolecular nanoparticles of ca. 12 nm in size by intrachain Cu(II)-catalyzed alkyne dimerization under high-dilution conditions, as revealed by SEC, H1-NMR, DLS and TEM measurements. Based on predictions from a recent compressible thermodynamic model, the resulting nanoparticles could be promising materials for the development of homogeneous, miscible PS-NPs / polycarbonate all-polymer nanocomposites. [ABSTRACT FROM AUTHOR]

In this work, the electrospinning of polymer solutions was used to produce mats with hydrophobic properties from a series of commercially available biodegradable and biocompatible polymers, such as poly(3-hydroxybutyric acid- co-3-hydroxyvaleric acid), poly(-lactide), polycaprolactone, and poly(-lactide). According to the results, to obtain hydrophobic properties, bead-like morphologies were the most adequate. For obtaining this type of morphology, the polymer concentration of the electrospun solution had to be sufficiently low, although below a limit concentration it was not possible to obtain hydrophobic surfaces. The results also showed that the crystallinity of the materials may influence the final hydrophobic properties. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 [ABSTRACT FROM AUTHOR]

Protection of acetylenic monomers is a common practice to avoid parasitic side reactions during polymerization. Herein, we report that redox-initiated RAFT polymerization allows the direct, room temperature synthesis of a variety of single-chain nanoparticle precursors (displaying narrow molecular weight dispersity, M[overline](W)/M[overline](n) = 1.12 -1.37 up to M[overline](W) = 100 kDa) containing well-defined amounts of naked, unprotected acetylenic functional groups available for rapid and quantitative intrachain cross-linking via metal-catalyzed carbon-carbon coupling (i.e., C-C "click" chemistry). To illustrate the useful "self-clickable" character of the new unprotected acetylenic precursors, single-chain nanoparticles have been prepared for the first time in a facile and highly efficient manner by copper-catalyzed alkyne homocoupling (i.e., Glaser-Hay coupling) at room temperature under normal air atmosphere., (Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Excellent dispersion of functionalized graphene (FG) sheets in polystyrene was achieved relying on the reaction of "living" poly(glycidyl phenyl ether) chains onto graphene sheets. The physical aging of polystyrene was substantially accelerated by the presence of FG sheets at low filler content, retaining film transparency and increasing the electrical conductivity., (This journal is © The Royal Society of Chemistry 2012)