Building upon our previous work, here we investigated synthesis of the telechelic macromonomers based on polyester diol using magnesium-titanium (IV) butoxide as catalyst. We hypothesized that this heterometallic catalytic system would enhance selectivity toward the secondary isocyanate function of isophorone diisocyanate (IPDI) and would result in shorter reaction times than our previous work with bismuth and zinc-based homometallic catalysts , while at the same time the materials would remain non-toxic. Towards this aim, we examined chemical structure and physio-chemical properties of the obtained macromonomers and we performed the cytotoxicity screening of fabricated elastomeric networks to assess their suitability for medical applications, especially for delivery of a precursor in minimally invasive medical procedures.