Production of Phenolic Foams Based on Phenol-Formaldehyde Oligomers of Reduced Toxicity and Material Consumption

Abstract

This article presents the results of studies considering the possibility of obtaining products based on phenol-formaldehyde oligomers of reduced toxicity, material consumption and corrosive activity. This is achieved by removing free phenol and formaldehyde monomers from the foaming composition and by more complete implementation of hydrodynamic processes during foaming of the composition. The article includes the results of studies on finding the ratio of the initial components and its effect on the corrosive activity of finished products. It is also considered the determination of the dependences of the toxicity and material consumption of phenolic foams on the pressure gradient of the foaming composition and the environment. For the research, the FRV-1A resole prepolymer and the VAG-3 foaming-hardening agent were used as raw materials. The content of phenol and formaldehyde monomers was determined by gas chromatography. In this work, the diagram of installation is developed and presented. It consists of a high-pressure machine, a mold, a vacuum pump, a vacuum gauge, air supply and air removal pipes. The results indicate that ensuring the formation of a cellular structure of phenolic foam in the low-pressure zone makes it possible to obtain heat-insulating products based on phenol-formaldehyde oligomers of reduced toxicity, material consumption and corrosive activity.