Free-energy Barrier to Melting of Single-chain Polymer Crystallite
نویسندگان
چکیده
We report Monte Carlo simulations of the melting of a singlepolymer crystallite. We find that, unlike most atomic and molecular crystals, such crystallites can be heated appreciably above their melting temperature before they transform to the disordered ”coil” state. The surface of the superheated crystallite is found to be disordered. The thickness of the disordered layer increases with superheating. However, the order-disorder transition is not gradual but sudden. Free-energy calculations reveal the presence of a large freeenergy barrier to melting. PACS: 64.70.Dv, 36.20.-r, 65.40.-b, 82.37.-j
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