Novel Poly(butylene succinate)-Based Ionomers with Sulfonated Succinate Units: Synthesis, Morphology, and the Unique Nucleation Effect on Crystallization

Poly(butylene succinate) (PBS) and PBS-based ionomers (PBSi's) with 0.3 and 1.2 mol-% of sodium sulfonated succinate unit were synthesized. The existence of ionic aggregates in the ionomer matrices was indicated by melt viscosity and glass transition data. It seems that the ionic aggregates have two opposing roles in crystallization: one is the induction of nucleation and the other is the interference with lamellar growth. Because of these two contrary effects, the crystallization behavior of the ionomers exhibited measurably different cooling rate-dependencies than that of the parent PBS. The rate varied distinctly with ionic content.