NOVOLAC RESIN AND METHOD FOR MANUFACTURING THE SAME

摘要

PURPOSE: A novolac resin is provided to improve flame retardancy by introducing a biphenyl structure, and to be used for manufacturing an epoxy resin with excellent flame retardancy. CONSTITUTION: A novolac resin comprises a weight average molecular weight of 500-4,000. In chemical formula 1, n is a positive integer, R1 is a single bond or at least one or more aromatic cyclic groups. Hydrogen in the aromatic cyclic group can be substituted by hydroxy, a C1-4 alkyl or C1-4 alkoxy, R2 is hydrogen, hydroxy, or a C1-10 alkyl group. The novolac resin has a number average molecular weight of 400-1,800 and a softening point of 90-160°C and a hydroxy equivalent of 190-260 g/eq.