Designing High-Mechanical-Property Organic Polymeric Crystals: Insights from Stress Dispersion and Energy Dissipation Strategies

Despite recent significant advancements in the applications of organic polymeric crystals (OPCs), a comprehensive understanding of the design principles for high-mechanical-property crystals remains somewhat elusive. Here, we investigate the mechanical properties of OPCs from the perspectives of stress dispersion and energy dissipation by examining crystals of a macrocycle and three analogous polymers with different solvent fillings, utilizing a novel research platform constructed via dative B-N bonds. Through a thorough mechanical study and investigation into the molecular mechanisms of these model topologies, it was demonstrated that structural expansion and solvent filling are effective pathways for enhancing the mechanical performance of the OPCs by employing stress dispersion and energy dissipation strategies. Overall, our research showcases precise control over the molecular topology of the OPC materials and elucidates specific pathways for stress dispersion and energy dissipation in modulating their mechanical performance, offering a broader design perspective for efficiently enhancing the mechanical properties of other crystalline polymers, such as metal-organic frameworks (MOFs) and covalent organic frameworks (COFs).