Abstract
The precursor of hydroxyl-terminated hyperbranched polyurethane (HBPU) was prepared from isophorone diisocyanate (IPDI), dimethylol propionic acid (DMPA) and diethanol amine (DEOA) via A2 + bB2 approach, and linear polyurethane (LPU) prepolymer was obtain by reacting IPDI, polytetramethylene glycol (PTMG) and DMPA. The aqueous dispersions were obtained based on the chain extension reactions of HBPU and isocyanate-terminated LPU. The structures of the HBPU and WPUs were proved by Fourier transform infrared (FT-IR) spectroscopy; the properties of cast film were measured by water resistance tests, tensile tests and thermal gravimetric analysis (TGA). The cast film of the resulting product (WPU-3) exhibits good comprehensive properties: better water resistance, tensile strength, and thermal stability.