Detailed photoradical ring-opening polymerization studies of 1,1-bis(ethoxycarbonyl)-2-vinylcyclopropane (VCP) and its methyl substituted derivate with significantly reduced volume shrinkage are presented.

A low volume shrinking vinylcyclopropane (VCP) monomer, showing both a high reactivity and a low viscosity, was obtained by applying a sterically hindered and isomeric spacer element, incorporating intermolecular amide hydrogen bonds. The resulting properties locate this VCP system in a pronounced range that so far no other efficient and radical polymerizable resin could enter.

Fast photo-polymerizable modular construction kit for making networks with extremely low shrinkage and varied mechanical properties.