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

Abstract

An ultrasound condition associated with phasetransfer 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 (R p ) 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 (E a ) and other thermodynamic parameters were calculated. The E a 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 9 10 4 g mol -1 .

Comparative investigation on radical polymerization of methyl and ethyl methacrylate under multi-site phase-transfer catalytic conditions

“…The thermodynamic parameters such as entropy of activation (ΔS # ), enthalpy of activation (ΔH # ) and free energy Table 1. The comparison of Ea value for different alkyl methacrylate under phase-transfer catalytic polymerization was reported [20,28,29]. The overall activation energy of 72.80 kJ/mol was reported for the polymerization of MMA using diphenyldisulphide and Cu (II) ion system [33].…”

“…It was found that the R p decreased in the following order: cyclohexanone > ethyl acetate > cyclohexane. An increase in the rate of polymerization was attributed to the increase in the polarity of the solvents, which facilitates greater transfer of peroxydisulfate ion from aqueous phase to organic phase [27][28][29] (Table 2).…”

Sonochemical fabrication of inorganic nanoparticles for applications in catalysis

“…Murugesan et al employed cetyltrimethylammonium bromide as a phase transfer catalyst to polymerize the monomer acrylonitrile in an ethyl acetate/water system under ultrasound (25 kHz/300 W). [165] In the case, the reactive radical was powerfully produced with the aid of ultrasound, and then the anion was extracted from aqueous phase by cetyltrimethylammonium bromide and transferred to organic phase, so the polymerization rate was highly enhanced compared to the silent condition. As well, they completed the polymerization of N-vinyl carbazole under ultrasound by using a multi-site phase transfer catalyst (i.e.…”

Kataliza Przeniesienia Międzyfazowego Jako Nowoczesna Technika W Syntezie Organicznej

“…Przykładem może być reakcja polimeryzacji akrylonitrylu prowadzona w układzie ciecz-ciecz wobec bromku cetylotrimetyloamoniowego (CTMAB) jako katalizatora PT (Rys. 9) [20]. Użycie ultradźwięków (25 kHz/300 W) spowodowało dwukrotne zwiększenie szybkości reakcji w porównaniu do reakcji bez ich udziału.…”

“…Użycie ultradźwięków (25 kHz/300 W) spowodowało dwukrotne zwiększenie szybkości reakcji w porównaniu do reakcji bez ich udziału. Rolą katalizatora przeniesienia międzyfazowego jest transport reaktywnego anionu rodnikowego z fazy wodnej do fazy organicznej, podczas gdy ultradźwięki przyspieszają tworzenie się rodników [20].…”