POLYETHER THIOUREA EPOXY CURING AGENTS

摘要

POLYETHER THIOUREA EPOXY CURING AGENTS (D#75,024-2-F) An improved curable epoxy resin composition of a vicinalpolyepoxide and an effective amount of a novel polyether thiourea curing agent is disclosed. The improved curable epoxy resins which are useful as coatings, castings, sealants, and adhesives show improved tensile shear strength, flexural strength, and ultimate elongation. The novel polyether thiourea curing agents of the instant invention are characterized by terminal primary amino groups and are formed by reaction of polyoxyalkylenepolyamines with thiourea, thiourea forming compounds or carbon disulfide. A preferred curing agent includes a mixture of a novel polyether thiourea formed by reaction of a polyoxypropylenepolyamine having a molecular weight of from about 200-2000 and an effective amount of carbon disulfide; and another known epoxy resin curing agent such as a polyoxyalkylenepolyamine in ratios of from about 5:1 to 1:5 by weight. I