Macroscopic Self-Assembly and Self-Healing Through Molecular Recognition

Cyclodextrins (CDs) were found to form inclusion complexes with some polymers with high selectivity by complexing with polymer side-chains. CD polymers formed complexes with guest polymers to give hydrogels which show self-healing properties that can be controlled by external stimuli, such as light and redox reactions. Host gels containing CD were found to adhere guest gels. Those host-guest gel assembly is selective and can be controlled by light, solvents, redox reactions, temperature, and pH. Mixtures of host polymers and guest polymers show sol-gel transition by light and redox reactions. Mixtures containing partially chemically cross-linking parts show expansion and contraction by some external stimuli. This system can be applied to develop artificial muscle and shape-memory systems.