Development of a sampling and analytical method for measuring the epoxy content of aerosols: I. Development of the analytical method.
Am Ind Hyg Assoc J 1987 Sep; 48(9):766-772
A method for measuring the epoxy content of epoxy resins was developed, as part of a program to develop a method for determining the epoxy content of aerosols. The method was based on hydrobromination of the epoxide in dimethylformamide. A volume of added in sufficient amount to give a 3:1 molar excess of bromide ion to the expected epoxy content of the sample. The excess bromide ion in the reaction mixture was determined by normal pulse polarography by measuring the limiting current at a pulse potential of -0.02 volts. The consumption of bromide ion during the reaction was related to the epoxy content of the sample. The method was validated by determining the epoxy content of the diglycidyl ether of bisphenol-A (DGBA) alone or in the presence of amines and components of commercial epoxy systems such as toluene, aliphatic ketones, and glycol ethers. The detection limit was 1 microequivalent (microeq) of DGBA. The accuracy was 2 percent and the coefficient of variation was 0.06. The presence of amines or the constituents of commercial epoxy resins did not interfere with the analysis. The authors conclude that the method provides a simple, accurate technique for determining the epoxy content of samples containing as little as 1microeq epoxide.
NIOSH-Author; Analytical-methods; Epoxy-compounds; Laboratory-techniques; Electrochemical-analysis; Laboratory-testing; Chemical-structure; Chemical-processing; Epoxy-resins
Robert F. Herrick, National Institute for Occupational Safety and Health, Division of Surveillance, Hazard Evaluations and Field Studies, lndustrywide Studies Branch, Cincinnati, OH 45226
American Industrial Hygiene Association Journal