Stereochemical Structure-Controlled Crystallization and Physical Property in Stereoisomeric Polymers

Stereoisomerism of polymers, arising from differences in spatial arrangement of bonded atoms (constitution), profoundly affects the crystallization, condensed matter structure, macroscopic property, and function of resulting materials. A comprehensive understanding of how stereoisomerism governs the crystallization and physical properties of polymers is essential for advancing the material design and tailoring the material properties for a specific application. In this Perspective, we mainly focus on the crystallization and physical performances of stereoisomeric polymers with the tactic, geometric (cis/trans) and chiral isomerization. We first summarize the crystallization behavior and physical property of stereoisomeric polymers with varying tacticities, with particular emphasis on the crystallizable atactic isomers and the cocrystallizable polymer blends of different tactic isomers. Then, we move our focus onto the geometry-isomeric (cis or trans) polymers and reveal how the geometric isomerization and cis/trans isomer ratios modulate their crystallization and physical property. In addition, the optical purity-dependent crystallization and physical property as well as the stereocomplex (SC) crystallization of chiral polymer isomers are discussed. We also highlight the emerging chiral polymer materials, such as self-reinforced networks and hierarchical assemblies, that exploit SC crystallization to achieve markedly improved properties. Finally, we outline future opportunities and research directions in this field.