A Sub-minute Curable Nanoadhesive with High Transparency, Strong Adhesion, and Excellent Flexibility

To achieve adhesion between two arbitrary substrates, a sub-minute curable dry nanoadhesive was devised in a one-step manner. The dry adhesive is composed of a copolymer film containing poly(glycidyl methacrylate) (pGMA) and poly(2-(dimethylamino)ethyl methacrylate) (pDMAEMA) segments, where the tertiary amine moiety in pDMAEMA acts as an initiator that triggers the ring-opening reaction of the epoxy ring in pGMA, leading to a self-cross-linking of the epoxide groups in pGMA. Optimization of curing condition resulted in dramatic enhancement of the adhesion strength to values exceeding 250 N/cm² of shear strength and 32.5 N/25 mm of peel strength. Also, strong bonds are observed in various types of substrate materials including glass, latex rubber, Si wafer, and many polymeric films to each other. Moreover, it maintained excellent adhesion against harsh mechanical, thermal, and chemical stresses. The copolymer-based nanoadhesive developed in this study will be highly advantageous for emerging flexible and foldable device applications.