BIPHY  >> Vol. 4 No. 2 (May 2016)

    具有环形拓扑结构聚合物刷的分子动力学研究
    Molecular Dynamics Study of Polymer Brushes with Ring Topology

  • 全文下载: PDF(2552KB) HTML   XML   PP.27-37   DOI: 10.12677/BIPHY.2016.42002  
  • 下载量: 957  浏览量: 3,166   国家自然科学基金支持

作者:  

万吴兵,吴晨旭:厦门大学软物质与生物仿生研究院,福建 厦门;厦门能源材料化学协同创新中心,福建 厦门;
Holger Merlitz:厦门大学软物质与生物仿生研究院,福建 厦门

关键词:
标度行为拓扑结构等温压缩Scaling Behavior Topological Structure Isothermal Compression

摘要:

运用分子动力学模拟,研究了不同拓扑结构的环形聚合物刷的静态结构,并对聚合物刷进行了等温压缩模拟。发现不同拓扑结构的聚合链的回转半径与链长的标度行为在不同方向的分量是不同的。对于回转半径z分量与链长的关系,不同拓扑结构的环形聚合物的标度值ν有些差别,但区分度不是特别的大。然而,对于回转半径的横向分量,不同拓扑结构的聚合链,所获得的标度值有明显的不同,而且随着拓扑限制变量的增大,所获得的标度值越来越小。聚合物刷的等温压缩模拟结果表明,聚合物刷在无外界压力或是在较小的压力压缩情况下,单体密度分布轮廓曲线是抛物线状,但随着压力的增大,单体密度分布是阶梯状。而且在压力很大的情况下,聚合物刷的拓扑效应会消失。

Static properties of polymer brushes with different topological ring structures are studied by using molecular dynamics simulation, and a compression of the brushes in isothermal process is carried out. It is found that the scaling behaviors between the radius of gyration and the chain length are very different in different directions. The scaling behavior between the gyration radii in the z-direction and the chain length shows little difference for different topological structures. While the transverse components reveal a quite different result. Furthermore, as the topological constraint becomes stronger, one obtains smaller scaling exponent. From the simulation of iso-thermal compression of the brush, we find that the profile of the monomer density is a step function rather than a parabolic one without compression. With force increasing, the topological effect will disappear in the brush system.

文章引用:
万吴兵, HolgerMerlitz, 吴晨旭. 具有环形拓扑结构聚合物刷的分子动力学研究[J]. 生物物理学, 2016, 4(2): 27-37. http://dx.doi.org/10.12677/BIPHY.2016.42002

参考文献

[1] Edgecombe, B.D., Stein, J.A., Fréchet, J.M., Xu, Z. and Kramer, E.J. (1998) The Role of Polymer Architecture in Strengthening Polymer-Polymer Interfaces: A Comparison of Graft, Block, and Random Copolymers Containing Hydro-gen-Bonding Moieties. Macromolecules, 31, 1292-1304.
http://dx.doi.org/10.1021/ma970832q
[2] Hawker, C.J. and Frechet, J.M. (1996) Comparison of Linear, Hyperbranched, and Dendritic Macromolecules. Step- Growth Polymers for High-Performance Materials, 624, 132-144.
http://dx.doi.org/10.1021/bk-1996-0624.ch007
[3] Guan, Z. (2002) Control of Polymer Topology by Chain—Walking Catalysts. Chemistry—A European Journal, 8, 3086-3092.
http://dx.doi.org/10.1002/1521-3765(20020715)8:14<3086::AID-CHEM3086>3.0.CO;2-L
[4] Hawker, C.J. (1999) Dendritic and Hyperbranched Macromolecules—Precisely Controlled Macromolecular Architectures. Advances in Polymer Science, 147, 113-160.
http://dx.doi.org/10.1007/3-540-49196-1_3
[5] Hudson, S., et al. (1997) Direct Visualization of Individual Cylindrical and Spherical Supramolecular Dendrimers. Science, 278, 449-452.
http://dx.doi.org/10.1126/science.278.5337.449
[6] Hill, D.J., Mio, M.J., Prince, R.B., Hughes, T.S. and Moore, J.S. (2001) A Field Guide to Foldamers. Chemical Reviews, 101, 3893-4012.
http://dx.doi.org/10.1021/cr990120t
[7] Kim, Y.H. (1998) Hyperbranched Polymers 10 Years after. Journal of Polymer Science Part A: Polymer Chemistry, 36, 1685-1698.
http://dx.doi.org/10.1002/(SICI)1099-0518(199808)36:11<1685::AID-POLA1>3.0.CO;2-R
[8] Tubiana, L., Orlandini, E. and Micheletti, C. (2011) Multiscale Entanglement in Ring Polymers under Spherical Confinement. Physical Review Letters, 107, Article ID: 188302.
http://dx.doi.org/10.1103/PhysRevLett.107.188302
[9] Borovik, A.S., Grosberg, A.Y. and Frank-Kamenetskii, M.D. (1994) Fractality of DNA Texts. Journal of Biomolecular Structure and Dynamics, 12, 655-669.
http://dx.doi.org/10.1080/07391102.1994.10508765
[10] Lieberman-Aiden, E., et al. (2009) Comprehensive Mapping of Long-Range Interactions Reveals Folding Principles of the Human Genome. Science, 326, 289-293.
http://dx.doi.org/10.1126/science.1181369
[11] Rosa, A. and Everaers, R. (2008) Structure and Dynamics of Interphase Chromosomes. PLOS Computational Biology, 4, e1000153.
http://dx.doi.org/10.1371/journal.pcbi.1000153
[12] Arsuaga, J., Vazquez, M., McGuirk, P., Trigueros, S. and Roca, J. (2005) DNA Knots Reveal a Chiral Organization of DNA in Phage Capsids. Proceedings of the National Academy of Sciences of the United States of America, 102, 9165- 9169.
http://dx.doi.org/10.1073/pnas.0409323102
[13] Marenduzzo, D., Orlandini, E., Stasiak, A., Tubiana, L. and Micheletti, C. (2009) DNA-DNA Interactions in Bacteriophage Capsids Are Responsible for the Observed DNA Knotting. Proceedings of the National Academy of Sciences, 106, 22269-22274.
http://dx.doi.org/10.1073/pnas.0907524106
[14] Zhulina, E. and Vilgis, T.A. (1995) Scaling Theory of Planar Brushes Formed by Branched Polymers. Macromolecules, 28, 1008-1015.
http://dx.doi.org/10.1021/ma00108a031
[15] Merlitz, H., Wu, C.-X. and Sommer, J.-U. (2011) Starlike Polymer Brushes. Macromolecules, 44, 7043-7049.
http://dx.doi.org/10.1021/ma201363u
[16] Polotsky, A.A., et al. (2010) Dendritic versus Linear Polymer Brushes: Self-Consistent Field Modeling, Scaling Theory, and Experiments. Macromolecules, 43, 9555-9566.
http://dx.doi.org/10.1021/ma101897x
[17] Cui, W., Su, C.-F., Wu, C.-X., Merlitz, H. and Sommer, J.-U. (2013) Numerical Evidences for a Free Energy Barrier in Starlike Polymer Brushes. The Journal of Chemical Physics, 139, Article ID: 134910.
http://dx.doi.org/10.1063/1.4823766
[18] Flikkema, E. and ten Brinke, G. (2000) Osmotic Pressure of Ring Polymer Solutions: A Monte Carlo Study. The Journal of Chemical Physics, 113, 11393-11395.
http://dx.doi.org/10.1063/1.1326908
[19] Suzuki, J., Takano, A. and Matsushita, Y. (2013) Topological Constraint in Ring Polymers under Theta Conditions Studied by Monte Carlo Simulation. The Journal of Chemical Physics, 138, Article ID: 024902.
http://dx.doi.org/10.1063/1.4773822
[20] Trefz, B. and Virnau, P. (2015) Scaling Behavior of Topologically Con-strained Polymer Rings in a Melt. Journal of Physics: Condensed Matter, 27, Article ID: 354110.
http://dx.doi.org/10.1088/0953-8984/27/35/354110
[21] He, S.-Z., Merlitz, H., Su, C.-F. and Wu, C.-X. (2013) Static and Dynamic Properties of Grafted Ring Polymer: Molecular Dynamics Simulation. Chinese Physics B, 22, Article ID: 016101.
[22] Li, B., Sun, Z.-Y. and An, L.-J. (2015) Effects of Topology on the Adsorption of Singly Tethered Ring Polymers to Attractive Surfaces. The Journal of Chemical Physics, 143, Article ID: 024908.
http://dx.doi.org/10.1063/1.4926775
[23] Halperin, A., Tirrell, M. and Lodge, T. (1992) Tethered Chains in Polymer Microstructures. Advances in Polymer Science, 100/1, 31-71.
http://dx.doi.org/10.1007/bfb0051635
[24] Binder, K., Kreer, T. and Milchev, A. (2011) Polymer Brushes under Flow and in Other Out-Of-Equilibrium Conditions. Soft Matter, 7, 7159-7172.
http://dx.doi.org/10.1039/c1sm05212h
[25] Alexander, S. (1977) Adsorption of Chain Molecules with a Polar Head a Scaling Description. Journal De Physique, 38, 983-987.
http://dx.doi.org/10.1051/jphys:01977003808098300
[26] Milner, S., Witten, T. and Cates, M. (1988) Theory of the Grafted Polymer Brush. Macromolecules, 21, 2610-2619.
http://dx.doi.org/10.1021/ma00186a051