Rapid self-healing capability as a metric for flexible spacing coating toward macroscopic supramolecular assembly of rigid building blocks

Macroscopic supramolecular assembly (MSA) refers to rapid molecular recognition between macroscopic components (>10 μm). Normally, MSA of rigid materials relies on a so-called “flexible spacing coating” beneath surface groups to provide high molecular mobility to realize multivalent binding. However, design principle of such coatings remains elusive. Here, we report an intuitive metric based on self-healing phenomena to judge whether a film can be a “flexible spacing coating” and apply this metric to extend film systems for MSA of rigid materials. The correlation between MSA and self-healing based on poly(ethylenimine)/poly(acrylic acid) films is revealed by similar dependence of assembly ratios and healing performance on film rigidity. Films capable of self-healing within 30 s can be used as flexible spacing coating for MSA. This metric is applied to three different film systems and proven effective to design coatings for MSA of rigid materials, which is applied in advanced manufacture of heterogeneous structure.