Kinetic study of the radical polymerization behavior of N‐(1‐phenylethylaminocarbonyl)methacrylamide

Abstract

Polymerization of N-(1-phenylethylaminocarbonyl)methacrylamide (PEACMA) with dimethyl 2,2Ј-azobisisobutyrate (MAIB) was kinetically studied in dimethyl sulfoxide (DMSO). The overall activation energy of the polymerization was estimated to be 84 kJ/mol. The initial polymerization rate (R p ) is given by R p ϭ k[MAIB] 0.6 [PEACMA] 0.9 at 60°C, being similar to that of the conventional radical polymerization. The polymerization system involved electron spin resonance (ESR) spectroscopically observable propagating poly(PEACMA) radical under the actual polymerization conditions. ESRdetermined rate constants of propagation and termination were 140 L/mol s and 3.4 ϫ 10 4 L/mol s at 60°C, respectively. The addition of LiCl accelerated the polymerization in N,N-dimethylformamide but did not in DMSO. The copolymerization of PEAC-MA(M 1 ) and styrene(M 2 ) with MAIB in DMSO at 60°C gave the following copolymerization parameters; r 1 ϭ 0.20, r 2 ϭ 0.51, Q 1 ϭ 0.59, and e 1 ϭ ϩ0.70.

Syndiotactic- and heterotactic-specific radical polymerization of N-n-propylmethacrylamide complexed with alkali metal ions

“…64,65 However, reports on ESR spectra of the radical polymerizations of methacrylamides are limited. 11,12,[66][67][68][69] Furthermore, almost all of the reports are concerned with radicals trapped in a variety of solid matrices. [66][67][68][69] This is probably because the radical concentration of the propagating radicals derived from methacrylamides is too low to be detected under practical conditions, owing to the cross-conjugation between the CvC-CvO and OvC-N-H groups in methacrylamides.…”

“…Stereoregularity is a function of monomer structure, initiator, solvent, and temperature. [5][6][7][8][9][10][11][12] This is mainly because N-alkylmethacrylamides can be polymerized only via a radical mechanism owing to their acidic N-H protons, which do not allow vinyl polymerizations via anionic and coordination mecha- nisms. 4 However, stereochemical studies on the polymerization of N-alkylmethacrylamides ( Fig.…”

“…Although the stereoregularities of the poly(N-alkylmethacrylamide)s reported so far have been moderately syndiotactic, [5][6][7][8][9][10][11][12] a limited number of stereospecific radical polymerizations of N-alkylmethacrylamides have been reported in the last two decades. [24][25][26][27][28] For instance, poly(N-methylmethacrylamide) [ poly(NMMAAm)] with rr triad = 95% was prepared in (CF 3 ) 2 CHOH at −78°C.…”

“…1), which are amide analogs of methacrylates, are scarce. [5][6][7][8][9][10][11][12] This is mainly because N-alkylmethacrylamides can be polymerized only via a radical mechanism owing to their acidic N-H protons, which do not allow vinyl polymerizations via anionic and coordination mecha-Fig. 1 Structures and abbreviations of methacrylamide and acrylamide derivatives described in this paper.…”

Determination of the Propagation Rate Coefficient of Vinyl Pivalate Based on EPR Quantification of the Propagating Radical Concentration

“…[31] More recently, the EPR method has been applied to further studies of the polymerizations of styrene, [37,38] acrylates, [39][40][41] methacrylates, [42][43][44][45][46][47] acryland methacrylamides, [48][49][50][51] a-substituted acrylates, [52,53] itaconate and related monomers, [54][55][56][57][58] as well as nonconjugated monomers. [59][60][61] Determination of k p by the EPR method and PLP-SEC has resulted in good agreement for styrene, [7,37] methyl methacrylate, [8,42] dodecyl methacrylate, [43,62] dimethyl itaconate, [22,63,64] and methyl a-(2-carbomethoxyethyl)…”