A qualitative and quantitative analysis of tertiary amines in restorative resins.

Previous investigations have shown that the type and the quantity of tertiary amine influence the properties of restorative resins. It was the purpose of the present work to analyze qualitatively and quantitatively the amines in commercial restorative resins. The amines were extracted with hydrochloric acid from chloroform solutions of the monomers. For the qualitative analysis the acid amine solution was made alkaline, the amine extracted with methylenechloride and isolated. The method of analysis was NMR-spectroscopy. The quantitative determination was performed by means of UV-spectra of the acid amine solutions. Sixteen brands were investigated, and three species of amine were identified. The amount of amine varied between 0.3% and 4% by weight of the monomer. Iit is probable that the information obtained will lead to a better understanding of the nature of restorative resins.