The structure of epoxy resins using NMR and GPC techniques



A series of epoxy resins based on the diglycidyl ethers of bisphenol A have been characterized by nuclear magnetic resonance and gel permeation chromatography. The ratio of molecular volume of a lightly branched molecule to that of a linear molecule of the same weight was found to vary as the square root of the ratio of the average maximal dimensions of the chain. At high degrees of chain branching, the ratio of the latter was to the power of three halves.