Pyrolysis of phenolic resins. IV.

Abstract Thermoset resins were made from benzene, naphthalene, phenanthrene, anthracene, or pyrene by condensation with p ‐xylylene dichloride in presence of stannic chloride. The extent of reaction, consequently the crosslink density, was controlled by measurement of the HCl evolved. The absence of oxidation was confirmed by infrared spectroscopy. On pyrolysis at 500, 1000, and 1200°C. in vacuo (after Madorsky) it was found that the yield of char was directly related to the number fraction of carbon atoms in the aromatic nucleus used. Benzene was anomalous, and all resins gave lower char yields than standard phenol formaldehyde resins.