Ultrasonic condition boosts up the rate of phase transfer catalyzed polymerization of acrylonitrile in two-phase system

Abstract

An ultrasound condition associated with phase-transfer catalyst (PTC) has great diverse applications in synthesis of various organic and polymeric materials because of its fast reaction and high yield in short period of time. Phase transfer catalyst (cetyltrimethylammonium bromide as PTC) extracts the reactive radical anion from aqueous phase and transfer to organic phase whilst ultrasound condition enhances the radical formation; consequently, acrylonitrile was polymerized in ethyl acetate/water two-phase system at 60 ± 1 °C under ultrasound (25 kHz/300 W) and silent condition. The rate of polymerization (Rp) was doubled under ultrasound compare to silent condition. The various experimental parameters such as monomer, initiator, catalyst and temperature, solvent polarity on the rate of polymerization was studied in both conditions. The activation energy (Ea) and other thermodynamic parameters were calculated. The Ea value of ultrasound condition supports the enhancement of rate of polymerization. On the basis of observed results, a suitable kinetic model, mechanism and effect of ultrasound in the rate of polymerization were discussed. The obtained polymer was analyzed by TG/DTA and FT-IR. The viscosity average molecular weight of the polymer was found to be 6.8526 × 104 g mol−1.