Polymerisation of methyl methacrylate - can the C=O group get involved? When methyl methacrylate undergoes free radical addition polymerisation, the C=C pi bond is broken during the process:



I'm wondering why the C=O pi bond doesn't get broken during the polymerisation. I suspect it may be because the C=O bond is stronger than the C=C bond, but are there any other ways to rationalise this?
C=O bond is strongly polar, and the cleavage of the double bond would rather involve heterolytic breaking with ions formed than homolytic with radicals.