Synthesis and characterization of new soluble multisite phase transfer catalysts and their catalysis in free radical polymerization of methyl methacrylate aided by ultrasound—A kinetic study

Abstract

Four different soluble phase transfer catalysts (PTCs) containing single, di, tri, and tetra active sites have been prepared and proved by FT‐IR, 1H NMR, 13C NMR, mass, elemental analysis, and conductivity measurement. The presence of the number of active sites in each catalyst was also been confirmed by determining their rate of polymerization of methyl methacrylate (MMA) using potassium peroxydisulfate (PDS) as a water soluble initiator in biphase medium. The comparative study reveals that the Rp of MMA determined in the presence of PTC combined with ultrasound has shown twofold enhancement in the activity than PTC alone. The observed order of activity was found to be of single‐site < di‐site < tri‐site < tetra‐site. Further, the thorough kinetic study of free radical polymerization of MMA has been investigated using superior tetra site viz., HBTAMPDTC and by varying the experimental parameters such as [MMA], [K2S2O8], [MPTC], and the temperature. Based on the observed kinetic results and activation parameters, a suitable mechanism was proposed. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012

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

“…The enhancement in the rate of phase-transfer catalyzed polymerization under ultrasound condition is attributed to the aforementioned reason. The combined approach of PTC and ultrasound is one of best techniques to enhance the reaction rate [60][61][62][63][64][65].…”

“…2). The reason was mainly attributed to the mechanical and chemical effect of ultrasound which can enhance the mixing of two phase effectively making like homogenous phase and helps the formation and transfer of more radical along with phase transfer catalytic polymerization process [60][61][62][63][64][65]. The polymerization of acrylonitrile with different PTC was reported [25,34,35,42] in the absence of ultrasound condition.…”

“…It is due to collision between initiator and catalyst was enhanced in the presence of ultrasound condition. In such a way more reactive radicals enhance the polymerization process [60][61][62][63][64][65]. Blank experiment: polymerization of acrylonitrile was performed by adopting aforementioned polymerization procedure without adding catalyst at 60 ± 1°C for 60 min under silent and ultrasonic conditions.…”

“…[49]. To the best of our knowledge the combined approach of PTC and ultrasound in free radical polymerization of vinyl monomers was limited [60][61][62][63][64][65]. By considering above all, we utilize this unique combined approach in polymerization of acrylonitrile (AN) using commercially available cetyltrimethylammonium bromide (CTMAB) as PTC and potassium peroxydisulfate (PDS) as water-soluble initiator in ethyl acetate/water two-phase system at 60 ± 1°C under inert atmosphere with silent and an ultrasound condition (25 kHz; 300 W).…”

New soluble multi-site phase transfer catalysts and their catalysis for dichlorocarbene addition to citronellal assisted by ultrasound—A kinetic study

“…Wang et al [11,12] also reported a kinetic study of dichlorocyclopropanation of 4-vinylcyclohexne and etherification of 4,4 -bis(chloromethyl)-1,1 -biphenyl and 1-butanol catalyzed by using new soluble MPTC containing two active sites and showed that MPTC exhibits more reactivity than single-site PTC. In our laboratory too, several multi-site phase transfer catalysts are reported for alkylation [13][14][15][16], dichlorocarbene addition [17,18], asymmetric synthesis [19][20][21][22], decarboxylation [23], functionalization of multi-walled carbon nano tubes [24,25] and polymerization [26] reactions.…”