Degradable vinyl polymer particles by radical aqueous emulsion copolymerization of methyl methacrylate and 5,6-benzo-2-methylene-1,3-dioxepane

With an increasing interest in the synthesis of (bio)degradable polymers, the synthesis of (bio)degradable vinyl polymer particles is attracting growing attention. In this work, degradable poly(methyl methacrylate) (PMMA) particles were synthesized by radical emulsion polymerization in water. A cyclic ketene acetal, 5,6-benzo-2-methylene-1,3-dioxepane (BMDO) was used as a co-monomer to introduce cleavable ester functions into the PMMA backbone. The stability of BMDO in aqueous media was studied and the degradation mechanism discussed in order to better comprehend the use of BMDO in emulsion and understand the incorporation of BMDO into the copolymer chains. Stable latexes containing various amounts of BMDO inserted units (from 2 to 6.4 mol%) were obtained. The degradation of the resulting copolymers was carried out in a basic medium and an average molar mass loss of 90% was observed.