Methyl α‐cyanoacrylate. II. Copolymerization studies

Abstract

synopsisCopolymerization of methyl a-cyanoacrylate with five reference monomers gave values e = +2.1 and of log Q = 0.65, with much scatter in the latter value. Alternating copolymers are formed by copolymerization with monomers of e = -0.8 or less. Bulk copolymerization with such monomers could not be accomplished, aa a rapid noncatalyzed polymerization occurred upon mixing even at 0°C. Random copolymers with methyl methacrylate could be prepared in bulk; those with ca. 10% methyl methacrylate had physical properties similar to the homopolymer of methyl a-cyanoacrylate, except that the heat distortion temperature was lowered 10-15°C. The alternating copolymers were more thermally stable than the random copolymers. Glass temperature values for alternating copolymers do not appear to agree with values predicted from equations for random copolymers.In the first paper of this series,' we discussed the free radical-initiated homopolymerization of methyl a-cyanoacrylate (MCyA) and compared its behavior with that of vinylidene cyanide. Gilbert and co-workers2 have reported an extensive study of the free radical-initiated copolymerization of vinylidene cyanide with a variety of monomers and have determined the Q and e parameters. The present study was undertaken to compare the reactivity of MCyA in similar copolymerizations arid also to determine some properties of the copolymers formed, as it was hoped that certain deficiencies in poly(methy1 a-cyanoacrylate) could be corrected in this manner. Although difficulties were encountered in the quantitative determination of reactivity ratios, the qualitative observations on the preparation and properties of these copolymers should be of interest.

Preparation, characterization and surface pKa values of poly(N-vinyl-2-pyrrolidone)/chitosan blend films

“…4. In the literature several conflicting values of a glass transition temperature (T g ) of PVP were found ranging from 54 8C to 175 8C [14][15][16][17][18][19]. These may be attributed to the large influence of sorbed moisture due to the hydrophilic nature of the material, as will be shown by present measurements.…”

Preparation and functionalization of linear and reductively degradable highly branched cyanoacrylate‐based polymers

“…It was found that poly(ECA‐ co ‐MMA) with various compositions ranging from homo‐polyECA, poly(ECA(10%)‐ co ‐MMA(90%)), polyECA(20%)‐ co ‐MMA(80%)), all the way to homo‐polyMMA, could be synthesized with compositions, which were the same as the feed ratio of the two comonomers. On the other hand, Kinsinger reported that for copolymerization of MCA ( M 1 ) and MMA ( M 2 ) in benzene at 60 °C, the values of the corresponding reactivity ratios, r 1 and r 2 , were 0.25 and 0.04, respectively . Assuming ECA had a similar reactivity to MCA, the reactivity ratios for ECA and MMA should be relatively small, which would force the random copolymerization to show a tendency to follow alternating copolymerization behavior.…”

Captodative olefins in polymer chemistry

“…A noticeable exception to the last rule is methyl a-ethylthioacrylate H2C--C(SEt)COOMe, whose 1/r 2 value of >100 [70] is higher than the values for the very electrophilic methyl ~-cyanoacrylate H2C=C(CN)COOMe (1/rz = t00) [101] and diethyl methylenemalonate H2C = C(COOEt)2 (1/rz = 33) [96,98]. As mentioned above its equivalent in the Correlations similar to Hammett relationships have been described in the literature for some 1,1-disubstituted olefins including captodative ones [96,98].…”