Polyurethane–polyisocyanurate foams modified with hydroxyl derivatives of rapeseed oil

Abstract

Three types of rapeseed oil-based polyols were used for synthesis of rigid polyurethane–polyisocyanurate (PUR–PIR) foams with three different isocyanate indices (150, 200 and 250). The bio-polyols were synthesized using epoxidation and opening of oxirane rings, transesterification with triethanolamine and transamidization with diethanolamine. Increasing isocyanate index gave rigid foams with increased thermal stability, improved mechanical properties and decreased flammability. Mechanical and thermal properties of rigid PUR–PIR foams depended also on type of bio-polyols. PUR–PIR systems modified with bio-polyol synthesized in the reaction of epoxidation and oxirane ring opening had the largest number of isotropic cells, what beneficially influenced on compressive strength and heat insulating properties of obtained foams.