Copolymerization of methacrylic anhydride with vinyl monomers

Abstract

Copolymerizations of methacrylic anhydride and a variety of common types of vinyl monomers were conducted in bulk and in solution at 60–80° with benzoyl peroxide catalyst. The copolymers were characterized by conversion, solubility in hot dimethyl sulfoxide, elementary analysis, and infrared spectroscopy. A copolymer composition equation was derived for a special divinyl–vinyl system in which the divinyl monomer would cyclize extensively during polymerization and give rise to soluble, although perhaps branched, copolymers. The results showed that both soluble and insoluble copolymers were obtained, depending on the comonomer used and experimental conditions under which the copolymerization was carried out. In general, soluble copolymers were formed under the following conditions: (a) the less reactive the comonomer in free radical copolymerizations; (b) the greater the dilution; (c) the greater the difference in the moles of the two components in charge; and (d) the lower the conversion. According to reactivity ratio determinations and a comparison with published data, the anhydride ring radical behaved like a methyl methacrylate radical. The key step which led to gelation was believed to be “ring interruption” by the comonomer (CH2 = CHR): The question why methacrylic anhydride does not gel in homopolymerization, however, still remains unresolved.

Cyclopolymerization and cyclocopolymerization

“…For example, copolymerization of methacrylic anhydride with a variety of vinyl monomers has been studied. 27 It was concluded that, in general, higher conversion to soluble copolymers was realized (a) the less reactive the comonomer in radical-initiated copolymerizations, (b) the greater the dilution, (c) the greater the difference in the molar concentration of the two monomers, and (d) the lower the conversion.…”

Preparation of soluble graft polymers from allyl benzoate/2,2′-azobis(N-(2-propenyl)-2-methylpropionamide) crosslinked polymers as insoluble polymeric azo initiators

“…In the copolymerization of monovinyl monomer (M 1 ) with divinyl monomer (M 2 ) bearing two equivalent double bonds, Eq. (1) to (4) can be given as the propagation reactions for copolymerization, when intramolecular cyclization of M 2 is not considered: On the basis of this reaction scheme, the copolymer composition equation is derived as follows: [15][16][17]…”

Dynamic covalent exchange induced cyclization in poly(methacrylic anhydride)

“…[3][4][5][6][7] For example, it has been shown that the cyclopolymerization of acrylic anhydride (AA) produces both five membered and six membered rings, while MAA exclusively produces six membered rings during polymerizations conducted up to 80 °C. [8][9][10][11][12][13][14][15][16][17][18][19][20][21][22] An additional and notable feature of the anhydride-containing MAA and AA diene monomers is that the anhydride moieties are able to undergo dynamic covalent exchange (DCE), which leads to the rearrangement of the polymer structure.…”