Embedding Media for 1-2 Micron Sectioning. 3. Hydroxyethyl Methacrylate-Benzoyl Peroxide Activated with Pyridine

Abstract

A hydroxyethyl methacrylate (HEMA) monomer medium containing 2-butoxyethanol as the plasticizer requites only one stock solution consisting of: 50 ml of 94 or 96% HEMA containing 200 ppm inhibitor (Rohm and Haas, Philadelphia) is mixed with 12 ml 2-butoxyethanol; 0.25 gm benzoyl peroxide is added and permitted to dissolve at 20-25 C. This mixture is activated by the addition of 0.8-1.0 ml of pyridine. Polymerization of the activated mixture is initated in 15-20 hr at 25 C and in 2-4 hr at 50 C; polymerization of the mixture is complete in 2-3 days and 3-6 hr, respectively. The activated monomer mixture is stable at temperatures below 18 C; hence infiltration of tissues may be extended to 7-10 days by keeping the mixture at 0 to -40 C.