ИСТИНА

We study conformational properties of a single multi-block copolymer chain consisting of flexible (F) and semi-flexible (S) blocks with equal composition of F- and S-units and with different affinity to a solvent. We perform Monte Carlo (MC) simulations based on the Stochastic Approximation algorithm [1, 2] which is one of the most recent realizations of flat-histogram-type MC algorithms [3]. SAMC algorithm is based on the idea of equally frequent sampling of all energy states of the system and accumulating the density of states function. We use the two- dimensional density of states function, which depends on the energy of intramolecular stiffness and on the energy of non-valence interactions. We present data on different non-trivial globular morphologies, including several structures with high orientational ordering of bonds, which we have obtained in our model for different values of the chain length, the block length and the stiffness parameter. Preliminary diagrams of states in variables temperature vs. stiffness parameter are also presented for different values of the block length. We compare our results with those obtained previously for a single SF-copolymer chain in a non-selective solvent [4, 5] and discuss the observed differences. We acknowledge the financial support from RFBR (grant 13-03-91334-NNIO-a) and DFG (project PA 473/10-1). We thank Moscow State University Supercomputer Center for providing the computational resources. References: [1] F. Liang, J. Stat. Phys. 2006, 122, 511. [2] F. Liang, C. Liu, R. J. Carroll, J. Amer. Stat. Ass. 2007, 102, 305. [3] W. Janke, W. Paul, Soft Matter, 2016, 12, 642. [4] S.V. Zablotskiy, J.A. Martemyanova, V.A. Ivanov, W. Paul, J. Chem. Phys., 2016, 144, 244903. [5] S.V. Zablotskiy, J.A. Martemyanova, V.A. Ivanov, W. Paul, Polym. Sci. Ser. A, 2016, 58, 899.