1,2-Benzenedicarboxylic acid, sulfo-, 1-(1-methyl-2-((2-methyl-1-oxo-2-propenyl)oxy)ethyl) ester 1-(2-(Methacryloyloxy)-1-methylethyl) hydrogen sulphophthalate 40139-96-6 EINECS 254-811-1 Methacryloxyisopropyl acid sulfophthalate