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We report the synthesis of a series of block copolymers consisting of a rod-like semiconducting poly(2,5-di(2'-ethylhexyloxy)-1,4-phenylenevinylene) (DEH-PPV) block and a flexible poly(lactic acid) (PLA) block that can be selectively degraded under mild conditions. Such selectively degradable block copolymers are designed as self-assembling templates for bulk heterojunction donor-acceptor layers in organic solar cells. A lamellar microphase-separated domain structure was identified for block copolymers with PLA volume fractions between 29 and 79% in bulk and thin films using SAXS, TEM, and AFM. Depending on the ratio of the two blocks we find either lamellae oriented parallel or perpendicular to the substrate in thin films., (Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The synthesis of π-conjugated polymers via an environmentally friendly procedure is generally challenging. Herein, we describe the synthesis of divanillin-based polyazomethines, which are derived from a potentially bio-based monomer. The polymerization is performed in 5 min under microwave irradiation without any metallic catalyst, with water as the only by-product. The vanillin-based polyazomethines were characterized by SEC, TGA, and UV-Vis spectroscopy. Model compounds were designed and characterized by X-ray diffraction and UV-Vis spectroscopy. The structure/properties study of vanillin-based azomethines used as models allowed us to unequivocally confirm the E configuration and to highlight the cross-conjugated nature of divanillin-based polymers. [ABSTRACT FROM AUTHOR]

The fabrication of organic solar cells from aqueous dispersions of photoactive nanoparticles has recently attracted the interest of the photovoltaic community, since these dispersions offer an eco-friendly solution for the fabrication of solar cells, avoiding the use of toxic solvents. In this work, aqueous dispersions of pure poly[n-9'-heptadecanyl-2,7-carbazole-alt-5,5-(4',7'-di-2-thienyl-2',1',3'-benzothiadiazole)] (PCDTBT) and [6,6]-phenyl-C71-butyricacid methyl ester (PC71BM) nanoparticles, as well as of composite PC71BM:PCDTBT nanoparticles, are prepared using the nanoprecipitation postpolymerization method. These dispersions are subsequently used to form the active layer of organic photovoltaic cells. Thin films of PC71BM and PCDTBT are obtained by spray deposition of the nanoparticles' dispersions, and are characterized using a combination of spectroscopic and microscopic techniques. Photo-voltaics that incorporate these active layers are fabricated thereafter. The impact of the annealing temperature and of the composition of the active layer on the efficiency of the solar cells is studied. [ABSTRACT FROM AUTHOR]

ABSTRACT Direct synthesis of charged hybrid particles in non-polar media has not been widely described in the literature but can lead to many applications such as electrophoretic displays. In this work, we propose a way to synthesize charged hybrid particles within the electrophoretic medium (Toluene or Isopar G) in the presence or not of additives (Charge Control Agent, CCA). The particles synthesis was performed by Nitroxide-mediated Radical Polymerization (NMRP) via dispersion polymerization in aliphatic hydrocarbon solvents leading to stable chargeable particles with a good size control. Hybrid particles are successfully charged by reaction with functional monomers or addition of CCA to obtain electrophoretic particles. The performance of a dual-color red/white ink in a display was demonstrated with a test-cell. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017, 55, 338-348 [ABSTRACT FROM AUTHOR]

ABSTRACT In this article, a simple route to obtain particles in one step from functional ionizable monomers in organic media by the use of acrylate-based macroinitiator synthesized by nitroxide-mediated radical polymerization is presented. Different positively ionizable monomers like 4-vinylpyridine, (dimethylamino)ethyl methacrylate, or negatively ionizable ones like methacrylic acid and acrylic acid were tested. Several parameters were studied to control the particles size, their stability in different organic media, and the possibility to crosslink them. Finally, well-defined, depending of conditions, functional latexes in organic media were produced in a simple way. This synthetic process constitutes the first step to produce electrophoretic inks for display applications such as electronic paper. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 4608-4617 [ABSTRACT FROM AUTHOR]

Abstract: Mixing in polymerization processes is an extremely important issue as uneven mixing inevitably leads to the synthesis of polymer with undesired characteristics. On the other hand, microeaction technology has enabled the development of extremely efficient micromixers which, within typical few milliseconds, allow mixing fluids at the microscale level. Recent developments in polymerization reaction engineering include the use of such micromixers to mix either initial reactants or reactive viscous solutions in multistep processes. Thus, polymers with improved control over their molecular weights and molecular weight distributions, chemical compositions and architectures can be synthesized. Micromixers can also be used to open new operating windows in which controlled polymerization can be performed faster or under less stringent reaction conditions. [Copyright &y& Elsevier]

Nitroxide-mediated radical polymerization (NMRP), in a continuous microtube reactor of inner diameter, of styrene and n-butyl acrylate at high temperature has been performed. The influence of the microsystem reactor on the control of the polymerization reaction was investigated and compared to a conventional labscale batch reactor. The main advantage of this microsystem is its ability to handle highly exothermic chemical reactions because of its high surface to volume ratio and the possibility to carry out the polymerization process in homogeneous conditions due to its small characteristic length. The discrepancy between microtube and batch reactors increases as the exothermicity of the monomer increases. In almost all experiments, the microtube reactor gives smallest polydispersity indices. Thus, the use of microstructured reactors can significantly improve the control of the polymerization. [Copyright &y& Elsevier]