Postpolymerization of gamma-irradiated formaldehyde at 20 to 150$sup 0$K

A calorimetric method suitable for use at liquid helium temperatures was used for low-temperature studies of post-irradiation polymerization of formaldehyde. Chain polymerization of formaldehyde was demonstrated at 15-20 deg K. The rate of heat release increased with tcmperature, then decreased, again increased to the melting point of formaldehyde, and then dropped to zero. The temperatures of the first rise and fall depended on the radiation dose. The effect of optical bleaching differed in the two fields, polymerization being more effectively depressed in the first field. The course of postpolymerization at low temperatures (20-7O deg K) apparently is governed by the presence of stabillzed ions. At higher temperatures, the process is governed by radical formation. (TTT)