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تسجيل مستخدم جديدFluctuations in Symmetric Diblock Copolymers: Testing A Recent Theory
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Composition fluctuations in disordered melts of symmetric diblock copolymers are studied by Monte Carlo simulation over a range of chain lengths and interaction strengths. Results are used to test three theories: (1) the random phase approximation (RPA), (2) the Fredrickson-Helfand (FH) theory, which was designed to describe large fluctuations near an order-disorder transition (ODT), and (3) a more recent renormalized one-loop (ROL) theory, which reduces to FH theory near the ODT, but which is found to be accurate over a much wider range of parameters.
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A renormalized one-loop theory (ROL) is used to calculate corrections to the random phase approximation (RPA) for the structure factor $Sc(q)$ in disordered diblock copolymer melts. Predictions are given for the peak intensity $S(q^{star})$, peak pos
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