Acrylic acid compromises

The crosslink formed by amino resins with hydroxyl functional acrylic copolymers is sensitive to acid-catalyzed hydrolytic degradation (13,14). The urethane crosslink formed by the reaction of hydroxyl functional acrylics and polyisocyanates is much more stable to this condition (15). This means that aiming for improved environmental resistance requires the more expensive polyisocyanate crosslinkers. Other crosslinking mechanisms of functional acrylics and crosslinkers will provide a better compromise of cost and etch performance, but these are often accompanied by other compromises. 

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