AbstractNew resins have been synthesized from o‐hydroxyacetophenone by reaction with substituted aromatic compounds and formaldehyde in the presence of various acids and bases as catalyst following two different techniques. The polymer samples are characterized by IR spectra. The solution, thermal, and chemical properties of the resins are investigated. The solubility parameters of the resins calculated according to the investigations of Small agree well with the experimental values. The resins are found to be fairly thermostable and the energy of activation is evaluated from TG curve by applying (i) Freeman‐Anderson method and (ii) Broido method.