摘要 |
Heat cured, thermoset protective surface coating films applied to a substrate are produced preferably by a dual cure of a polymeric ionomeric binder comprising zinc modified carboxyl functional epoxy-ester polymers. The epoxy-ester polymer contains both carboxy and hydroxyl functionality and coreacts with a zinc salt selected from a zinc carbonate or an organic zinc salt having a pKa above about 3.0. Upon heat curing, the carboxyl and hydroxyl groups crosslink while the zinc forms a zinc cluster to produce a thermoset film.
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