Advances in Phenolic Resin as a Curing Agent for Epoxy Resin, Part II

─The Diversity Coming into View Through Phenolic Substances in CAS Registry─

Abstract

Following to a previous work, this article takes up several types of phenolic resins which include renewable resources-based type, and functionalized types having heat resistance and low dielectric contant. There are three typical renewable resources actually used as raw material for phenolic resin; one is terpene, another is CNSL (cashew nut shell liquid), and the other is lignin. Phenolic resin, as a curing agent of epoxy resin, has been constantly improved to be imparted with the functions which reflect the technological trends of the time. At the present, better dielectric properties are most needed in the electric and electronic fields. Taking an example of the property improvement, introduction of active ester group to phenolic resin is found to provide superior dielectric properties after curing with epoxy resin. The CAS registration number and the chemical structure of each phenolic resin and its derivatives, are summarized in tabular form similar to the previous review article.