使用 390-LC 多检测器套件 (MDS) 通过 GPC 黏度检测分析环氧树脂

Epoxy resins are complex materials manufactured by the reaction of a ‘resin’ with a ‘hardener’. This produces a cross-linked polymer that is extremely strong, tough and may be used to bond materials together. The resin component of the mixture is an epoxide pre-polymer, typically produced by the reaction of an epoxide with bisphenol-A. The resulting short-chain material contains pendant –OH and epoxide functionalities and is polar in nature. The molecular weight of the epoxide chains in the resin is important as this influences the curing rate of the final epoxy resin formulation when mixed with the hardener, however, accurate molecular weights are difficult to obtain due to the complex, inhomogeneous nature of the epoxide polymer chains. Gel permeation chromatography (GPC) is a well-known technique for assessing the molecular weight distribution of polymers, a property that influences many physical characteristics such as the curing time of epoxy resins. GPC viscometry employing a viscometer in combination with a differential refractive index detector has the advantage of allowing the determination of accurate molecular weights for structurally complex polymers and co-polymers via the Universal Calibration approach. Using this methodology, the same molecular weights are determined for samples regardless of the standards used to create the calibration. This application note describes the analysis of two samples of epoxide pre-polymers by GPC viscometry