Benzyldimethylamine(BDMA) and dimethylaminoethanol as the catalysts of choice for epoxy resin embedding media

Abstract

INTRODUCTION: By long held tradition, many epoxy resin embedding media are catalyzed with 2,4,6-Tri(dimethylaminomethyl)phenol (DMP-30). Embedding media polymerized in this manner are widely-used and produce acceptable results, nevertheless they show high viscosity, a rapid loss in fluidity, and ultimately a shortened useful pot-life necessary for complete specimen infiltration. Perhaps using less viscous catalysts, such as Benzyldimethylamine (BDMA) or Dimethylaminoethanol (DMAE), would yield embedding media with lowered viscosity and prolonged fluidity, both very important characteristics that would ensure complete infiltration and strengthening of tissues subsequent to microtomy and ultrastructural study.MATERIALS & METHODS: The amine catalysts BDMA, DMAE, and DMP-30 were tested for Average Flow Time (AFT) and Volume Flow Rate (VFR) by recording the time necessary for 9 ml of each component to flow from a vertically oriented viscosimeter. Viscosity (cp), which is a relative measure of fluidity and a real correlate of AFT/VFR, then was calculated with the Hagen-Poiseville relation for laminar flow as applied to fluids. Embed 812 and LX112 media were prepared and catalyzed either with BDMA, DMAE, or DMP-30 and their AFT, VFR, and cp similarly determined @ 5, 30, and 60 minute intervals after initial mixing.