A series of waterborne polyurethane (WPU) dispersions were synthesized from isophorone diisocyanate (IPDI), polyester glycol (T 1136) and dimethylolpropionic acid (DMPA) via prepolymer mixture. It was found that the s...A series of waterborne polyurethane (WPU) dispersions were synthesized from isophorone diisocyanate (IPDI), polyester glycol (T 1136) and dimethylolpropionic acid (DMPA) via prepolymer mixture. It was found that the solid content, hydrolytic stability of PU emulsion and the cold crack properties of the cast film of WPU could be improved by using polyester and polyether as soft segment. The mechanical properties of the cast film increased and the elongation at break decreased with increasing content of hard segment and NCO/OH ratio. The water resistance, solvent resistance and wetting rub properties of the cast film of WPU would be improved by increasing the amount of TMP. Testing of the cast film showed natural gloss with silky hand feel, excellent adhesion and cold crack properties, water resistance, solvent resistance, and rub resistance at 40% hard segment content, 1.3-1.5 of NCO/OH ratio and 3%-5% of TMP content.展开更多
文摘A series of waterborne polyurethane (WPU) dispersions were synthesized from isophorone diisocyanate (IPDI), polyester glycol (T 1136) and dimethylolpropionic acid (DMPA) via prepolymer mixture. It was found that the solid content, hydrolytic stability of PU emulsion and the cold crack properties of the cast film of WPU could be improved by using polyester and polyether as soft segment. The mechanical properties of the cast film increased and the elongation at break decreased with increasing content of hard segment and NCO/OH ratio. The water resistance, solvent resistance and wetting rub properties of the cast film of WPU would be improved by increasing the amount of TMP. Testing of the cast film showed natural gloss with silky hand feel, excellent adhesion and cold crack properties, water resistance, solvent resistance, and rub resistance at 40% hard segment content, 1.3-1.5 of NCO/OH ratio and 3%-5% of TMP content.
