A polymerizable dimethicone copolyol macromer composition is synthesized by reacting itaconic anhydride with a dimethicone copolyol. During the reaction itaconic anhydride spontaneously isomerizes to citraconic anhydride which in turn is esterified by the dimethicone copolyol. The obtained macromers are copolymerizable with olefinically unsaturated monomers. Polymers containing the macromer repeating units are useful in a variety of applications including personal care, textile and industrial formulations to deliver softness, lubricity, fixative, water repellency, gloss, surface modification, and surfactant properties.