Small-Angle X-ray Scattering Analysis on the Estimation of Interaction Parameter of Poly(n-butyl acrylate)-b-poly(methyl methacrylate)

The temperature dependence of the Flory-Huggins interaction parameter chi for poly(n-butyl acrylate)-b-poly(methyl methacrylate) (PBA-b-PMMA) was quantified from small-angle X-ray scattering (SAXS) analysis using random phase approximation (RPA) theory. It was found from the chi estimation (chi=0.0103+14.76/T) that the enthalpic contribution, chi H, a measure for temperature susceptibility of chi, is 1.7-4.5 folds smaller for PBA-b-PMMA than for the conventional styrene-diene-based block copolymers, which have been widely used for thermoplastic elastomers. This finding suggests that these fully acrylic components can be a desirable chemical pair for constituting terpolymers applied for thermally stable and mechanically resilient elastomers.

Automated summary

The temperature dependence of the Flory-Huggins interaction parameter chi for PBA-b-PMMA was quantified using SAXS analysis and RPA theory. The enthalpic contribution of chi was found to be 1.7-4.5 times smaller for PBA-b-PMMA compared to styrene-diene-based block copolymers. This suggests that these fully acrylic components are desirable for constituting terpolymers used in thermally stable and mechanically resilient elastomers.