AbstractFor many years, benzoyl peroxide has been used as an initiator for polymerization of methylmethacrylate. In 1983, di(4-tert-butylcyclohexyl) peroxydicarbonate, trade-named Perkadox 16, was introduced in the literature as an alternative to benzoyl peroxide.When Perkadox 16 was incorporated into the protocols in our respective laboratories, we found that it had some unique advantages over benzoyl peroxide, including reduced preparation time and reproducible polymerization. However, during the course of the last 4 years, we have begun to experience some problems. This paper presents some of the problems that have been associated with Perkadox 16 in 2 different laboratories and how each laboratory has worked out a system to avoid them. (The J Histotechnol17:343, 1994)