Hydrolytic stability and physical properties of waterborne polyurethane based on hydrolytically stable polyol

New type of polyester polyol with alkyl side groups, viz. poly(2,4-diethyl-1,5-pentamethylene adipate) glycol (PDPAD) was synthesized and applied to improve the hydrolytic stability of polyurethane dispersions (PUD), and the results were compared with conventional poly(tetrarnethylene adipate) glycol (PTAD)-based PUD. It was found that PDPAD-based PUD gave much higher hydrolytic stability in spite of great water swell than the PTAD-based PUD which showed higher hardness, modulus, and tensile strength. Tailor-made properties were possibly obtained by combining the two types of polyol.