Effect of ionic aggregation on ionomer chain dimensions. 1. Telechelic polystyrenes

peer reviewedCarboxy-telechelic polystyrenes with degrees of polymerization of ca. 70 were examined by small-angle neutron scattering in the Na+ ionomer and methyl ester forms to ascertain the effect of ionic aggregation on the chain dimensions. The ionomers contain ionic aggregates, as demonstrated by smallangle X-ray scattering. The chain dimensions were found to be identical for the ionomer and ester, in agreement with the predictions of Squires et al. but in disagreement with the theories of Forsman and Dreyfus. Detailed analysis of the data showed that the contacts between the two isotopic types were random, as intended. The data were satisfactorily described by a polydisperse assembly of wormlike chains, with a Kuhn statistical length comparable to that for homopolystyrene