Plastic phenolic foam prodn. - with simultaneous polycondensation, foaming and hardening, using specific phenol(s)

摘要

A plastic phenolic foam is prepd. by polycondensing phenol and formaldehyde with simultaneous foaming and hardening in presence of a foaming agent and an acid or alkaline catalyst. The phenol used is specifically pyrocatechol, hydroquinone, resorcinol, 5-methyl-resorcinol, alkyl resorcinol derived from bituminous shale, phenols derived from bituminous shale and various association of those phenols. The prod. is used for thermal insulation of buildings, naval structures, in the mechanical and chemical industries and refrigeration engineering. The process is industrially feasible and avoids the need for prepg. an intermediate prod. such as a resol type PF resin. It can be achieved in a wide temp. range (10-90 degrees C) within a much shorter time than previously (5-90 secs). Hardening occurs both with acid and alkaline catalysts, these catalyst also serving as polycondensation catalysts.