Beardsley T M, Matsen M W
Department of Chemical Engineering, Department of Physics & Astronomy, and Waterloo Institute for Nanotechnology, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada.
J Chem Phys. 2021 Mar 28;154(12):124902. doi: 10.1063/5.0046167.
The order-disorder transition (ODT) of diblock copolymer melts is evaluated for an invariant polymerization index of N¯=10, using field-theoretic simulations (FTS) supplemented by a partial saddle-point approximation for incompressibility. For computational efficiency, the FTS are performed using the discrete Gaussian-chain model, and results are then mapped onto the continuous model using a linear approximation for the Flory-Huggins χ parameter. Particular attention is paid to the complex phase window. Results are found to be consistent with the well-established understanding that the gyroid phase extends down to the ODT. Furthermore, our simulations are the first to predict that the Fddd phase survives fluctuation effects, consistent with experiments.
对于聚合指数N¯ = 10的不变值，使用场论模拟（FTS）并辅以不可压缩性的部分鞍点近似，来评估双嵌段共聚物熔体的有序-无序转变（ODT）。为了提高计算效率，使用离散高斯链模型进行FTS，然后使用Flory-Huggins χ参数的线性近似将结果映射到连续模型上。特别关注复杂相窗口。结果与已确立的认识一致，即螺旋状相一直延伸到ODT。此外，我们的模拟首次预测Fddd相在涨落效应下仍然存在，这与实验结果相符。
