Development of a sampling and analytical method for measuring the epoxy content of aerosols: I. Development of the...

A method has been developed for determining the quantity of the epoxide functional group in pure epoxy resins, resins in partially-cured mixtures with amine curing agents, and commercial epoxy surface coatings. The method is based upon the reaction of the epoxide group with bromide in the presence of acid, with measurement of excess bromide in the reaction mixture by normal pulse polarography. The method extends the range of previously reported methods for epoxy analysis to samples containing 1 to 100 microequivalents (microeq) of epoxide functionality, while maintaining good precision and accuracy (coefficient of variation less than 0.06; accuracy within 2% of expected). The method has been developed for application to analysis of the epoxy content of environmental aerosols such as those of epoxy paint sprays.