| 摘要 |
<p>A process for producing a modified phenolic resin which comprises heating and stirring a heavy oil or pitch together with a formaldehyde compound and a phenol represented by the formula (I) (wherein R1 is a C¿2-10?, linear or branched, unsaturated hydrocarbon group having one or two unsaturated bonds; p is 1 or 2; X is C1-5 alkyl; and q is 0 or 1) in the presence of an acid catalyst to conduct polycondensation, the amounts of the formaldehyde compound and the phenol being 0.3 to 25 mol in terms of formaldehyde amount and 0.5 to 50 mol, respectively, per mol of the heavy oil or pitch. The modified phenol obtained by the process has flowability around room temperature because it has a far lower melting point than conventional modified phenolic resins obtained from a heavy oil or pitch. It further has a low melt viscosity and hence excellent moldability. When used in combination with an epoxy resin, the modified phenol can give a molded article excellent not only in heat resistance, moisture resistance, corrosion resistance, adhesion, etc. but also in dimensional stability and mechanical properties including strength.</p> |
