Stock material or miscellaneous articles – Composite – Of epoxy ether
Patent
1996-12-30
1997-11-11
Krass, Frederick
Stock material or miscellaneous articles
Composite
Of epoxy ether
523428, 525524, 525526, 528 94, 528 98, 428413, 427386, C08L 6302, C08G 5914
Patent
active
056861850
ABSTRACT:
A thermosetting epoxy resin powder coating composition is provided that comprises an epoxy resin composed of a diglycidyl ether of bisphenol A, a curing agent composed of a bisphenol A encapped diglycidyl ether of bisphenol A, and a cure catalyst composed of an imidazole adducted to a diglycidyl ether of bisphenol A, in which the ratio of curing agent to epoxy resin is below 70% stoichiometry, and preferably between about 10% and 60% stoichiometry. The thermosetting epoxy resin powder coating composition not only exhibits the desired flexibility and fast cure speeds, but also exhibits superior adhesion and superior resistance to delamination and cathodic disbondment, preferably having cathodic disbondment values typically less than 4 mm radial disbondment, and preferably less than 2 mm radial disbondment. Such properties are highly advantageous for protective powder coatings used on rebars and pipelines. The marked improvement in adhesion combined with good flow out behavior provide the thermosetting epoxy resin powder coating composition with the ability to effectively adhere to steel strappings and other dirty, oily and scaly metallic substrates. The thermosetting epoxy resin powder coating composition also begins to cure at very low temperatures for acceptable oven bake times. This property is highly advantageous for protective and decorative powder coatings used on wood and other heat sensitive substrates.
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Berstler Roy M.
Correll Glenn D.
Benjamin Steven C.
Krass Frederick
Morton International Inc.
White Gerald K.
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