Glagolev Mikhail K, Vasilevskaya Valentina V, Khokhlov Alexei R
A. N. Nesmeyanov Institute of Organoelement Compounds of Russian Academy of Sciences, Vavilova St. 28, 119991 Moscow, Russia.
J Chem Phys. 2016 Jul 28;145(4):044904. doi: 10.1063/1.4959861.
Impact of mixture composition on self-organization in concentrated solutions of stiff helical and flexible macromolecules was studied by means of molecular dynamics simulation. The macromolecules were composed of identical amphiphilic monomer units but a fraction f of macromolecules had stiff helical backbones and the remaining chains were flexible. In poor solvents the compacted flexible macromolecules coexist with bundles or filament clusters from few intertwined stiff helical macromolecules. The increase of relative content f of helical macromolecules leads to increase of the length of helical clusters, to alignment of clusters with each other, and then to liquid-crystalline-like ordering along a single direction. The formation of filament clusters causes segregation of helical and flexible macromolecules and the alignment of the filaments induces effective liquid-like ordering of flexible macromolecules. A visual analysis and calculation of order parameter relaying the anisotropy of diffraction allow concluding that transition from disordered to liquid-crystalline state proceeds sharply at relatively low content of stiff components.
通过分子动力学模拟研究了混合物组成对刚性螺旋和柔性大分子浓溶液中自组装的影响。大分子由相同的两亲单体单元组成，但一部分（f）大分子具有刚性螺旋主链，其余链是柔性的。在不良溶剂中，压实的柔性大分子与少数相互缠绕的刚性螺旋大分子形成的束或细丝簇共存。螺旋大分子相对含量f的增加导致螺旋簇长度增加，簇彼此排列，然后沿单一方向形成类似液晶的有序排列。细丝簇的形成导致螺旋和柔性大分子的分离，细丝的排列诱导柔性大分子形成有效的类似液体的有序排列。通过可视化分析和计算反映衍射各向异性的序参量，可以得出结论：在刚性组分含量相对较低时，从无序态到液晶态的转变会急剧发生。
