Synthesis and polymerization of phosphorus-containing acrylates

Novel phosphorus-containing acrylate monomers were synthesized by two different routes. The first involved the reaction of ethyl a-chloromethyl acrylate and t-butyl alpha-bromomethyl acrylate with diethylphosphonoacetic acid. The monomers were bulk- and solution-polymerized at 56-64 degreesC with 2,2'-azobisisobutyronitrile. The ethyl ester monomer showed a high crosslinking tendency under these conditions. The selective hydrolysis of the ethyl ester phosphonic ester compound was carried out with trimethylsilyl bromide, producing a phosphonic acid monomer. In the second route, ethyl a-hydroxymethyl acrylate and t-butyl a-hydroxymethyl acrylate were reacted with diethylchlorophosphate. The bulk homopolymerization and copolymerization of these monomers with methyl methacrylate and 2,2'-azobisisobutyronitrile gave soluble polymers. The attempted hydrolysis of the monomers was unsuccessful because of the loss of the diethylphosphate group. The relative reactivities of the monomers in the photopolymerizations were also compared. The ethyl a-hydroxymethyl acrylate/diethylphosphonic acid monomer showed higher reactivity than the other monomers, which may explain the crosslinking during the polymerization of this monomer. The reactivities of other derivatives were similar, but the rates of polymerization were slow in comparison with those of methyl methacrylate. (C) 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 3221-3231, 2002.