The free‐radical polymerization of styrene with p‐nitrobenzyl triphenyl phosphonium ylide as an initiator in dioxane at 80 ± 1 °C in a dilatometer under a nitrogen atmosphere for 150 min resulted in a syndiotactic polymer, as evidenced by IR, 1H NMR, and 13C NMR spectroscopy. A 1H NMR spectrum showed methylene protons as triplets; 13C NMR signals of the phenyl ipso carbons were used for the determination of the tacticity. The system followed ideal kinetics. Gel permeation chromatography data were used evaluate the weight‐average molecular weight. The overall activation energy was 47 kJ/mol. Electron spin resonance spectroscopy confirmed the initiation by the phenyl radical obtained by the dissociation of the ylide and the free‐radical mode of polymerization. Differential scanning calorimetry studies showed the glass‐transition temperature of the polymer to be 342 K. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 6524–6533, 2005

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Solution terpolymerization of styrene (St), methyl methacrylate (MMA) and acrylonitrile (AN) was carried out in dioxane at 65 ± 0.1• C for 120 min using p-nitrobenzyltriphenyl phosphonium ylide as radical initiator. (MMA + AN) = 0.06 and r 2 (St) = 0.005, employing the Kelen-Tüdos method. It confirmed the alternating nature of the terpolymer. The terpolymer was characterized using 13 C NMR, gel permeation chromatography and thermogravimetric differential thermal analysis. Electron spin resonance spectroscopy confirmed the presence of the phenyl radical responsible for initiation.

Oxazolidone modified epoxy resin blends can be prepared with dianhydrides to form thermosets with higher thermal stability. Curing the oxazolidone modified resin is an addition reaction, which offers better thermal properties and improved chemical resistance. Chemical reactions that take place during cure, determine resin morphology and properties of cured thermosets. Such epoxy resin systems are used for various reinforcements because they offer significant advantage over metals in area of weight saving and corrosion resistance and for use in glass fabric reinforced flame retardants.

Synthesis of terpolymers consisting of two electron-donating monomers, viz. styrene and vinyl acetate with one electron-accepting monomer, <i>i.e.</i> acrylonitrile, initiated by p-nitrobenzyl triphenyl phosphonim ylide in dioxane as diluent at 65°C for 150 min has been studied. The kinetic expression is <i>R_pα</i>[I]^0.8[Sty] ^1.2[VA] ^1.4 [AN]^1.2. The terpolymer composition was determined by the Kelen-Tüdos method. The values of reactivity ratios using <i>r</i>₁ (Sty + VA) = 0.1 and <i>r</i>₂ (AN) = 0.005. The overall activation energy is 46 kJ●mol●L^–1. The formation of terpolymer is confirmed by the FTIR spectra showing bands at 3030 cm^–1, 1598 cm^–1, and 2362 cm^–1, confirming the presence of phenyl, acetoxy and nitrile group respectively. The terpolymer has been characterized by ¹H-Nuclear Magnetic Resonance, ¹³C-Nuclear Magnetic Resonance. The Differential Scanning Calorimetric curve shows the <i>T_g</i> of the polymer as 149.5°C. A scanning electron microscope confirms the polymer to be phosphorus free. Electron.Spin.Resonance spectra confirms phenyl radical responsible for initiation