Retention of Propanal and Diacetyl in Experimental Resins

Abstract

Peutzfeldt A Retention of propanal and diacetyl in experimental resins.

The degree of evaporation from experimental resins containing 0–40 mol% propanal or diacetyl was determined over a month period at 60°C. From the results the maximum evaporation possible, M∞ was calculated for each resin and was found to vary between 0.28% and 7.51% by weight. At low contents of propanal or diacetyl, M, remained unchanged as compared with the control resins without additive. At higher contents of additive, M, increased significantly. In resins based on BisGMA and TEGDMA, propanal was retained to a lesser extent than diacetyl. In resins based on UEDMA and HEMA, propanal was retained to a greater extent than diacetyl. This study confirms that propanal and diacetyl become bound in the polymer structure, and theories as to the reaction mechanisms are presented.