Polymerization of cyclic monomers, 4. Synthesis and radical polymerization of bi- and trifunctional 2-vinylcyclopropanes

Multifunctional 2‐vinylcyclopropanes were synthesized by esterification of the 1‐methoxycarbonyl‐2‐vinylcyclopropane‐1‐carboxylic acid with ethylene glycol, 1,1,1‐trimethylolpropane or 1,4‐cyclohexanediol in the presence of 1,3‐dicyclohexylcarbodiimide (DCC). The structure of the new vinylcyclopropanes was confirmed by elemental analysis, IR, 1H NMR and 13C NMR spectroscopy. The radical polymerization of the 2‐vinylcyclopropanes in bulk with 2,2′‐azoisobutyronitrile (AIBN) results in transparent crosslinked polymers. The polymerization of the liquid monomers is accompanied by a low shrinkage in volume.