After photocuring under both atmospheres, the obtained elastomeric films showed relatively low values of gel fraction (see Table ), as compared to our previous results with homometallic Zn and Bi catalysts, where the gel fraction was ~93% . Importantly, as in previous paper only a slight difference in gel fraction was observed between the two curing atmospheres. The highest value obtained for PrMg-Ti_0.5 (75%) and the overall trend was similar to that for the results of the degree of acrylation.