Dissipative crystallization of aqueous solution of sodium polymethacrylate

Drying dissipative structures of aqueous solution of sodium polymethacrylate (NaPMA) were studied on a cover glass, a watch glass, and a glass dish. Any convectional and sedimentation patterns did not appear during the course of dryness. Several important findings on the drying patterns are reported. Firstly, spherulite and hedrite dissipative crystals were observed when the polymer solutions were dried. The crystalline structures changed from hedrites to spherulites as polymer concentration increased. Secondary, the coupled structures of the spherulites and the broad rings were observed for NaPMA at the outside edge of the broad ring. However, the coupled crystalline structures of the lamellaes from the broad ring and the spherulites, which were observed for poly(ethylene glycol) (Okubo et al. 2009), were not observed clearly for NaPMA system. Thirdly, size of the broad ring at the outside edge of the dried film increased sharply as polymer concentration increased.