122325-31-9 2-((2-Methyl-1-oxo-2-propenyl)oxy)benzoic acid homopolymer 39276-30-7 Benzoic acid, 2-((2-methyl-1-oxo-2-propenyl)oxy)-, homopolymer Poly(2-methacryloyloxybenzoic acid) Polymethacryloyloxybenzoic acid