Process for producing modified phenolic resin

Abstract

A process for producing a modified phenolic resin, comprising heating a heavy oil or pitch of given average molecular weight and, per mol, calculated from the average molecular weight, of the heavy oil or pitch; 0.3 to 25 mol, in terms of formaldehyde, a formaldehyde compound and 0.5 to 50 mol of a phenol of the formula (I) (wherein R1 represents a linear or branched unsaturated hydrocarbon group having 1 to 2 unsaturated bonds and having 2 to 10 carbon atoms, p is 1 or 2, X represents an alkyl group having 1 to 5 carbon atoms, and q is 0 or 1) under stirring in the presence of an acid catalyst to thereby effect a polycondensation. The modified phenolic resin obtained by this process, as compared with the conventional modified phenolic resin produced from a heavy oil or pitch as a feedstock, has an extremely low softening point so as to be flowable at about room temperature and has also a low melt viscosity, thereby ensuring very excellent moldability. Further, in combination with an epoxy resin, the modified phenolic resin can be formed into a molded article which is excellent in not only heat resistance, moisture resistance, corrosion resistance and adhesive force but also mechanical properties such as dimensional stability and strength.

Dependencies are inferred from the claim text.