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Plasticization of random styrene-(JV-alkyl-4-vinylpyridinium iodide) ionomers was carried out using one of the following methods: quatemization of the vinylpyridine groups with n-iodoalkanes, alkylation of the styrene with 1-decene, or external plasticization with diethylbenzene. The materials thus prepared were analyzed using dynamic mechanical and small-angle X-ray scattering techniques. It was shown that plasticization of the styrene matrix induced clustering in these materials, while the ionomers in which the vinylpyridine groups were plasticized retained the characteristics of one-phase materials. The amount of material incorporated into the clusters was seen to vary depending on the mobility of the plasticizer, thus the fraction of clustered material in the externally plasticized ionomers was significantly greater than in the internally plasticized materials.

The glass transition temperatures (Tg) and dynamic mechanical properties of random copolymers of styrene‐4‐vinylpyridine quaternized with iodoalkanes are presented for vinylpyridine contents up to ten percent and pendant alkyl chains up to ten carbons in length. Two linear relationships, between ion content and glass transition temperature and between pendant alkyl chain length and the Tg, are observed. An equation is presented that can be used to predict the Tg for such copolymers based on their ion contents and alkyl chain lengths.

Organic salts are known to affect the contact charge developed between two polymers. When ionomers are present, the charge often increases monotonically with the salt concentration and the charge has been ascribed to the transfer of ions. A model is presented which relates the charge with salt concentration in the polymer blend. In this model, only dissociated ions but not ion pair ions are proposed to transfer. The model incorporates ion pair dissociation (K1) and ion pair aggregation (K) and shows that when ion pair aggregation is minimal, the concentration of dissociated ions scales near linearly with the square root of the concentration of salt in the blend. The linear relationship between the charge and [salt]1/2 is demonstrated. It is further shown that the equilibrated charge which is established is limited by the concentration of dissociated ions on the surface of the polymer and not by the surface provided by the second material.