Hamed Daemi - Department of Polyurethane, Iran Polymer & Petrochemical Institute, Tehran, Iran
Mehdi Barikani - Department of Polyurethane, Iran Polymer & Petrochemical Institute, Tehran, Iran

Linear hydroxyl-terminated polybutadiene (LHTPB) is an unsaturated polyolefin diol and characterized by its low glass transition temperature and high elastic behavior. LHTPBs are used in formulation of polyurethanes (PUs) to donate them significant elasticity and toughness. Most of catalysts used for synthesis of HTPB-based PUs are toxic metal-based complexes. Here, we develop a novel metal-free methodology for synthesis of dual-crosslinked HTPB modified with urethane and isocyanurate networks from the reaction of toluene diisocyanate (TDI) and hydroxyl-terminated polybutadiene (HTPB) in the presence of N-hydroxyphthalimide (NHPI) as a green, effective and commercially available cyclotrimerization catalyst. Based on TGA results, the dual-crosslinked HTPB samples demonstrated highly thermal stability compared to neat PUs at elevated temperatures up to 450 °C because of thermally stable isocyanurate groups in their chemical structure.

Hydroxyl-terminated polybutadiene, Poly(urethane-isocyanurate), NHydroxyphthalimide,Catalyst, Thermal stability