Isocyanate-Free Polyurea Synthesis via Ru-Catalyzed Carbene Insertion into the N-H Bonds of Urea. - de Zwart FJ; Laan PCM; van Leeuwen NS; Bobylev EO; Amstalden van Hove ER; Mathew S; Yan N; Flapper J; van den Berg KJ; Reek JNH; de Bruin B (Macromolecules, 2022)