Non-conventional Phenolic Resins — An Overview on Recent Advances

Abstract

Phenolic resins even now are useful in view of their several salient features and the unlimited commercial potentiality. Innovative research for overcoming the inherent shortcoming of these systems with regard to processability, brittleness,

oxidative resistance etc. has gained momentum. The introduction of addition-cure phenolics answers partly to these problems. The paper consolidate the very recent developments in the field of non-conventional phenolics. The strategies

adopted for structural modifications through introduction of thermally stable addition curable groups such as, Phenyl maleimide, phenyl maleimide-allylphenol, propargyl ether, acetylene and phenyl ethynyl are described briefly. When the structural modification alone does not answer to the problem, strategy of reactive and non-reactive blending and control of the cure and morphology of the network prove effective. The cure behaviour and properties of the cured matrices are reviewed. Reference is made also to the synthesis and adhesive evaluation of selected modified phenolic resins and their blends. Some of these resins show good prospects for application in aerospace structural and thermo-structural applications, and as high performance structural adhesives with definite advantages.