Investigation of Molecular Weight Dependency of Hansen Solubility Parameters for Poly(methyl methacrylate) Using Inverse Gas Chromatography

The Hansen solubility parameters (HSP), of substances, are crucial for evaluating the affinity between materials. Generally, the experimental determination of HSP is achieved using the Hansen solubility sphere method. However, this approach raises several questions relating to the experimental conditions used. In this study, we use inverse gas chromatography to determine the HSP of poly(methyl methacrylate) (PMMA). We measured the HSP for five different molecular weights of PMMA (in the range 3190–1,155,000) to establish the molecular weight dependency in polymers. The results indicated that in the molecular weight range 3190–9500, δ_d increased with increasing molecular weight, δ_p decreased, and δ_h showed no significant change. However, in the molecular weight range 9500–1,155,000, no significant changes were observed for any of the parameters. It can therefore be concluded that for PMMA with a molecular weight of at least 9500, the molecular weight dependency of the HSP is almost negligible.