Studies on the radical polymerization of N-vinyl 2-pyrrolidone initiated by diphenyl ditelluride

Abstract

N-vinyl pyrrolidone (NVP) was polymerized in dioxan at 60 ± 0.1°C for 1 h using diphenyl ditelluride as radical initiator. The system follows ideal kinetics i.e. R p α [DPDT]0.5[NVP]. The activation energy and dissociation constant is computed as 46 kJ mol−1 and 1.1 × 10−11 s−1, respectively. The polymer was characterized with the help of FTIR, 1H-NMR, 13C-NMR, ESR spectroscopy. The FT-IR spectrum showed bands at 1660–1680 cm−1 due to combination of >C = O and C–N stretching. The gyromagnetic constant ‘g’ has been computed as 2.2203. The main product of this reaction were poly(N-vinylpyrrolidone)s with phenyl tellanyl ends. The presence of tellurium in polymer is confirmed by ICP analysis. The DSC shows the T g of poly(N-vinylpyrrolidone) is 168°C due to rigid pyrrolidane group. The TGA showed that polymer was stable up to 380°C.The GPC studies showed that the weight average molecular weight decreases with increase of [DPDT].