The effects of solvents on the chemical decomposition of foamed phenol resin in high-temperature conditions

In this study, thermosetting resin such as foamed phenol resin (FPR) powder was solubilized and decomposed into their monomeric and oligomeric compounds in high temperature fluids. Solvents play important roles as stable physical medium at high temperature and reactive chemical reagents to accelerate decomposition reaction of the thermosetting resin. The decomposition of FPR into their monomers occurred by cleaving methylene bond of the resin selectively via the ionic reaction. The effects of solvent which has a hydroxyl group and methylene carbon atoms (high affinity with FPR) on the solubilization of FPR were confirmed by the reaction in high-temperature m-cresol and straight-chain alcohols. More than 90 % of FPR was solubilized in the reaction in m-cresol and 1-heptanol at 350 °C for 2 h suggesting the presence of the solubilization route other than methylene chain scission.