| 摘要 |
<p>There is now provided a method for coating a substrate using a one package composition which is stored stable at room temperature and which can be cured into a thermoset coating upon application of heat. The storage stable mixture is made of at least a Mannich base and a polyamine compound, applied to a substrate, and cured at elevated temperatures to effect the exchange and liberation of amine groups from the Mannich base by the polyamine compound. The Mannich base is a reaction product of at least: ai) a phenolic compound; aii) an aldehyde; and aiii) a secondary amine, such that each aromatic group of the Mannich base has at least two tertiary amino groups bonded through aldehyde residues to each aromatic ring of the phenolic compound. The polyamine compound is a reaction product of: aiv) a primary amine, which optionally can contain secondary amine groups; and av) an epoxy compound having at least one 1,2-epoxy group(s) per molecule. The polyamine compound advantageously contains more than two active amine sites. The one package composition is storage stable and does not react at room temperature. The coating is cured rapidly, and is durable and hard because the equivalent weight of the polyamine compound is built up with epoxide compounds while simultaneously increasing the available number of amine crosslinking sites.</p> |
