Comparison of clustering in various acrylate ionomers

The clustering behavior of three well clustered acrylate ionomers, i.e. poly(ethyl acrylate -co-Na acrylate) (PEA), poly(styrene-co-Na acrylate) (PS), and poly(vinylcyclohexane-co-Na acrylate) (PVCH) ionomers, was compared. It was found that the cluster phase became dominant at ca. 5 mol% for the PEA and PS ionomers but at 9 mol% for the PVCH ionomer. In addition, the temperature differences between the matrix and cluster Tgs were 54, 55 and 49°C for the PEA, PS, and PVCH ionomers, respectively. The very similar values for the PEA and PS ionomers, in spite of their difference in matrix Tgs themselves, led to a postulation that the PEA ionomers have bigger multiplets and longer persistence length than the PS ionomers.