Gel Formation in Reversibly Cross-Linking Polymers

By means of Langevin dynamics simulations, we investigate the gel formation randomly functionalized polymers in solution, with ability to form both intra- and intermolecular reversible bonds. Under highly dilute conditions, these soft nano-objects (so-called single-chain nanoparticles, SCNPs), resulting from purely intramolecular cross-linking reactive functional groups. Here show that competition between bonds at finite concentration is governed by a delicate balance various entropic contributions leads density dependent effective valence. System-spanning networks are formed relatively low monomer densities their stability mediated just small number connections per chain. The furthermore can induce non-monotonic dependence polymer size on for long bond lifetimes. Concomitantly, percolating cluster adopt an structure characteristic self-avoiding chains, which constitutes strong contrast fractal globular behavior irreversible SCNPs crowded solutions topological interactions (no bonds). Finally, study system, displays signatures expected gel-forming systems. An interesting emerges reorganization cluster. relaxation mostly diffusion over distances, through breaking bonds, chains do not leave Regarding few transiently free, time they spend until reattach solely strength.