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Nanocomposite particles of poly(chlorotrifluoroethylene-co-ethylvinyl ether) [poly(CTFE-co-EVE)]/poly(styrene acrylate) (PSA)/SiO2 were prepared with poly(CTFE-co-EVE)/PSA [CS(FS); core–shell (CS) fluoro surfactant (FS)] and hydrophilic SiO2 nanoparticles by a solution mixing method. This method yielded a homogeneous dispersion of hydrophilic SiO2 nanoparticles in the CS(FS) matrix. The nanocomposite particle composition was confirmed by Fourier transform infrared spectroscopy and thermogravimetric analysis. A slight improvement in the thermal stability was observed and the glass-transition temperature of the nanocomposite particles increased compared with the CS(FS) matrix. A remarkable enhancement was observed in the mechanical properties with an increase in the tensile strength from 1.1 to 6.2 MPa and with an increase in the elongation at break from 209.6 to 350.1% for the films with 15 wt % SiO2. The presence of a wettable PSA shell on the fluorocore made interaction possible with SiO2; this made it more hygroscopic with a decent water uptake capacity and an enhanced water contact angle. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2012

This article describes a study on thermal behavior of poly(vinylidene fluoride-chlorotrifluoroetheylene) [poly(VDF-CTFE)] copolymers as polymeric binders of specific interest for high energy materials (HEMs) composites by thermal analytical techniques. The non-isothermal thermogravimetry (TG) for poly (VDF-CTFE) copolymers was recorded in air and N2 atmospheres. The results of TG thermograms show that poly(VDF-CTFE) copolymers get degrade at lower temperature when in air than in N2 atmosphere. In the derivative curve, there was single maximum degradation peak (Tmax) indicating one-stage degradation of poly(VDF-CTFE) copolymers for all the samples. The other thermal properties such as glass transition temperature (Tg) and degradation temperature (Td) for poly(VDF-CTFE) copolymers were measured by employing differential scanning calorimeter (DSC) technique. The kinetic parameters related to thermal degradation of poly(VDF-CTFE) copolymers were investigated through non-isothermal Kissinger kinetic method using DSC method. The activation energies for thermal degradation of poly(VDF-CTFE) copolymers were found in a range of 218–278 kJ/mol. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013

Core shell latex particles with a glassy core and a low Tg polymeric shell are usually preferred. More so, the glassy core happens to be a fluoropolymer with a shell polymer that helps in processability. We describe here the preparation and characterization of core shell nanoparticles consisting of poly(chlorotrifluoroethylene-co-ethylvinylether) as core encapsulated in poly(styrene-acrylate) copolymer shell using seeded emulsion polymerization method under kinetically controlled monomer starved conditions. Properties of the emulsion using surfactants (fluoro/conventional) and surfactant free conditions were investigated. Average size (100 nm), spherical shape and core–shell morphology of the latex particles was confirmed by dynamic light scattering and transmission electron microscopy. Absence of CF and CCl peaks in X-ray photoelectron spectroscopy proves that cores are completely covered. Polymerization in the presence of fluorocarbon surfactant was found to give optimum features like narrow size distribution, good shell deposition and no traces of agglomeration. Films of core shell latex particles exhibited improved transparency and enhanced water contact angles thus making them suitable for applications in various fields including coatings. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011

A highly regiospecific reduction of vinyl epoxides to allyl alcohols with Cp2TiCl is described.

First total synthesis of (2E,4E,8E,10Z)-N-(2-methyl propyl)-2,4,8,10-dodecatetraene amide ( 1 ), by the condensation of (4E,6Z)-octadienyl phenyl sulfone ( 2 ) and ethyl-4-oxobutanoate ( 3 ) followed by double elimination reaction, which involves easily accessible reagents and simple transformations is described.

A new titanium(III) mediated [(C5H5)2TiCl] reduction of 2,3-epoxy alcohols to alk-1-en-3-ols is described.