Figure 8.

Formation of bridges at low concentration of open stickers $c_{\mathit{open}}<c_{\mathit{open}}^{\ast }\approx 1/R_0^3$. (a) Direct bonding of two open stickers (red circles) across the interface. (b) An open sticker (depicted by a red circle) hops across the interface (from black to blue chain) by partner exchange, converting a loop into a bridge, while keeping the number of open stickers unchanged.