Use of inverse gas chromatography to quantify interactions in anhydride cured epoxy resins

Previous work has shown that the inverse gas chromatography (IGC) method combined with Flory–Huggins and solubility parameter theories could be used to quantify interactions in an amine cured epoxy resin matrix. In the present communication the same procedures have been adopted for an anhydride cured epoxy resin matrix. The solubility parameter at 298 K thereby obtained for the cured resin was 20–6 (MPa)1/2, which lies between the corresponding values of 18.8(MPa)1/2 and 22.5 (MPa)1/2 for the precursors, viz. Epikote 828 (an epoxide resin) and phthalic anhydride, respectively. It was noted that great care must be exercised regarding choice of solvent used for deposition of phthalic anhydride on a glass bead support because of reaction to phthaclic acid. Similar consderations apply to the choice of probes used.