Novel NISO-Based Crosslinkers for 2K Silyl-Polyurethanes and 1K Moisture Cure Coatings

摘要

Traditional polyurethane coatings are well known for their enhanced chemical resistances, weatherability, low-to-ambient cure capability, and tough physical properties, both as two component (2K) systems and as one-component (1K) moisture curable systems. However, the isocyanate groups that impart high reactivity with hydroxyl-functional resins are also reactive with amines and hydroxyl groups on the top layer of biological surfaces, requiring adequate Personal Protection Equipment (PPE) during handling and use. Ambient cure, non-isocyanate functional polyurethane coatings are of interest principally as they could potentially impart the physical properties of polyurethanes due to internal urethane groups, while having other reactive moieties that would crosslink to give excellent chemical resistances.This paper describes an analysis of coatings that have been crosslinked using novel silane terminated crosslinkers containing urethane groups within their backbone. These crosslinkers were used both in two component systems to crosslink hydroxyl-functional resins and in one component self-crosslinking, moisture-cure systems.