Dynamic mechanical properties of polystyrene‐co‐styrenesulfonic acid copolymers neutralized with aliphatic diamines

Abstract

In this article, we reported the effects of the addition of various aliphatic diamines (ADAs) on the dynamic mechanical properties of poly(styrene-co-styrenesulfonic acid) copolymers. It was found that the ionic modulus decreased with increasing chain length of ADAs but increased for the ADA12-containing ionomers. Upon the neutralization of the copolymers with ADAs, a minor change in the size and position of the matrix loss tangent peak was observed. However, the position of the cluster loss tangent peaks shifted to lower temperatures, and the shift rate depended on the chain length of ADAs. Thus, it was suggested that the ADAs acted mainly as preferential plasticizer for the cluster regions. In addition, the effect of the amount of ADA on the difference between the matrix and cluster temperatures of the ionomers was strongest than that of the type of ADA or ion content. The X-ray peak of ADA12 suggested that the ADA12 acted both as plasticizer and as filler.

Effects of Styrene Ionomers on the Dispersion of Asphaltenes in Crude Heavy Oil

“…Alkali metal hydroxides are usually used as neutralizing agents to neutralize the acid groups of copolymers to make ionomers, but sometimes, alkyl amines (R–NH 2 ) are also used to neutralize sulfonic acid groups of SSA copolymers. − In this case, the proton (H + ) of the sulfonic acid is transferred to the amine (R–NH 2 ) to form an ammonium-sulfonate (R–NH 3 + – O 3 S−) ion pair, the interaction of which is much weaker than the interaction between alkali metal-sulfonate (M + – O 3 S−) ion pairs. , This is due to the difference in the size of the cations. That is, the larger the cation (R–NH 3 + > M + ), the weaker the strength of the ionic interaction.…”