Effect of Ketone and Hydrazine Self-Crosslinking Reaction on Polyurethane Emulsion

摘要

A kind of multiple amine chain extender which consists of (EDA-di (diacetone propionamido) (EDDP) and EDA-diacetone propionamido (EDP)), was synthesized firstly. Then the extender reacted with polyurethane prepolymer emulsion to form a polyurethane emulsion, containing carbonyl groups in the side chains of molecules. The resulting emulsion would increase room temperature self-crosslinking reaction between the carbonyl groups and added adipic dihydrazid (ADH) in the process of drying but not during the emulsion being stored, to improve the properties of the latex film. Effects of self-crosslinking reaction on performance of the polyurethane emulsion were systematically studied. The results showed that the water resistance of the latex film boosted greatly, and some other properties including elongation at break and tensile strength improved as well.