Related Experiment Video
Updated: Sep 21, 2025

Controlling the Size, Shape and Stability of Supramolecular Polymers in Water
Published on: August 2, 2012
Inside the Ionic Aggregates Constrained by Covalently Attached Polymer Chain Segments: Order or Disorder?
Zixin Yu1, Jie Wang1, Zhen Hu1
1Hubei Provincial Key Laboratory of Green Materials for Light Industry, Collaborative Innovation Center of Green Light-weight Materials and Processing, and School of Materials and Chemical Engineering, Hubei University of Technology, Wuhan, Hubei 430068, China.
Abstract:
When a small-molecule ionic crystal is group-substituted with polymer chain-segments to form an ionomer, do its constrained ionic aggregates maintain ordered internal structures? This work presents, for a Na-salt sulfonated-polystyrene ionomer, reconciled TEM electron-diffraction schlieren textures and WAXS Bragg-type reflections from the ionic-aggregate nanodomains, which solidly prove the aggregates' internal (mono)crystalline order. The observed DSC endotherm of the ionomer, identified by WAXS as an order-disorder transition interior to its aggregates, gradually becomes enhanced over a 3-month, room-temperature physical aging process, indicating that the aggregates' ordering is a slow relaxation process in which the degree of order increases with time. This work corroborates an uncommon form of order, i.e., polymer-bound small-molecule ionic (quasi)crystal, which is supplementary to the order phenomena in small molecules, polymers, and liquid crystals.
Related Concept Videos
Ionic Crystal Structures
Most monatomic ions behave as charged spheres, and their attraction for ions of opposite charge is the same in every direction. Consequently, stable structures for ionic compounds result (1) when ions of one charge are surrounded by as many ions as possible of the opposite...
Polymer Classification: Crystallinity
Crystalline domains are the regions where polymer chains are aligned in an orderly manner and held together in proximity by intermolecular forces. For example, chains in the crystalline domains of polyethylene and nylon are bound together by van der Waals...
Intrinsically Disordered Proteins
Ionic Bonding and Electron Transfer
Anionic Chain-Growth Polymerization: Mechanism
Cationic Chain-Growth Polymerization: Mechanism

