Cure, viscoelastic and mechanical properties of hydroxylated polyester melamine high solids coatings

This paper presents the effects of diol structure and acetoacetylation on cure, viscoelastic and mechanical properties of hydroxylated polyesters (HPS)/ hexamethoxymethylmelamine (HMMM) clear coatings. Acetoacetylation of HPs is a potential tool for researchers to get the equivalent or superior performance at higher application solids than their base counterpart. Differential Scanning Calorimetry (DSC), Dynamic Mechanical Thermal Analyzer (DMTA) and Thermo Gravimetric Analysis (TGA) have been utilized to study the cure, cure and viscoelastic behavior and thermal stability of the coatings respectively. The crosslink density (XLD) and elastically effective chain length between crosslinks (M(c)) of the coating films has also been determined. Furthermore, the mechanical film properties such as tensile properties, adhesion strength and hardness were measured and related to chemical composition. The results indicate that the combined analysis helps in correlating the structure property relationship with end use properties. (C) 2002 Kluwer Academic Publishers.