Preparation and properties of a biobased polyurethane reinforced by a dual crosslinking topological network

In this paper, polytetrahydrofuran (PTMEG) and isophorone diisocyanate (IPDI) were used as raw materials to synthesize prepolymers, and then castor oil (CO) was added to synthesize high-strength bio-based polyurethanes. The effect of castor oil content on the properties of COPU was investigated in this paper, and its heat resistance and mechanical properties firstly increased and then decreased with the increase of CO content.COPU3 showed the best comprehensive mechanical properties, with a tensile strength of 22.55 MPa and an elongation at break of 1008.57 %. The reason for its high strength is explored; it may be that hydrogen bonding and CO form a double cross-linking topological network, which enhances the mechanical strength of the polymer. These studies provide far-reaching value for the application of bio-based materials.