Analytical Sciences

Distribution Analysis of Epoxy Groups in Polymers by Derivatization–Electron Probe X-ray Microanalysis

Motoyasu SUGIURA,* Keiko FUKUMOTO,* Atsushi MURASE,* and Kazumasa UEDA**

*Materials Analysis & Evaluation Div., Toyota Central R & D Labs. Inc., Nagakute, Aichi 480-1192, Japan
**Department of Chemistry and Chemical Engineering, Kanazawa University, Kodatsuno, Kanazawa 920-8667, Japan

An analytical method, referred to as "erivatization-lectron probe X-ray micro-nalysis (XMA)", has been developed to determine the distribution of a small amount of the functional groups in a polymer. The suitable conditions for the derivatization reaction with epoxy groups, which contribute to the hardening reactions of polymers, were investigated. It was found that epoxy groups in polymers were derivatized selectively using gas-phase esterification with hydrochloric acid (HCl). The most suitable amount of HCl in a 50 ml vial was 300 ul. After setting a sample in the vessel without directly contacting the reagent, by reacting the reagent and the sample at 25°C for 1 h, the highest reaction yield and selectivity were obtained. By derivatization-XMA using this reaction condition, the measurement of the distribution of epoxy groups in the polymer became feasible. Actual applications to a depth analysis of epoxy groups in the hardened acrylic coating and epoxy resin proved that this method is useful for the characterization of polymers and for the study of the hardening reaction of polymers.

J-STAGE: View this article in J-STAGE