Equilibrium morphologies and force extension behavior for polymers with hydrophobic patches : role of quenched disorder.

Equilibrium morphologies and mechanical properties of copolymers with hydrophobic segments are explored using Langevin dynamics simulations. The interplay between different length scales, namely, persistence length ℓp, and disorder correlation length p, in addition to the fraction of hydrophobic patches f, determines the equilibrium morphology and in turn their mechanical response. Globular and coil phases for flexible chains and core-shell and looped morphologies for semi-flexible ones are reported. Consequently, a force induced globule-coil transition for flexible chains is observed for all disorder realizations, with p dictating the force vs. extension curves. Semi-flexible chains with same ℓp and f but different p, show different sequences of force-induced conformational transitions on account of their differing equilibrium conformations