Study on the Synthesis and Properties of Biodegradable Waterborne Polyurethane

Taking L-Lysine Diisocyanate (LDI) as hard segments, poly-ε-caprolactone diol (PCL) as soft segments, a kind of nontoxic and biodegradable waterborne polyurethanes were synthesized using two-step polymerization. And then the effects of isocyanate/macroglycol molar ratio(NCO/OH, R value), the 1,4-butylene glycol (BDO) content and prepolymerization temperature on the properties of waterborne polyurethanes were investigated. The experimental results showed that when R value is 1.5, the BDO content used is 4% and the reaction temperature is 80°C, the products prepared were best in application. The mechanical property tests showed that it has good mechanical properties, tensile strength is up to 46.5MPa and the loss amounts of the hydrolytic degradation after 80 days is 42%. The waterborne polyurethanes prepared have excellent biodegradability, which can be widely used as a biological medical material.