Lateral Ordering during SelfOrganization of Statistical Multiblock Copolymers 1
Arkadiy D. Litmanovich, Vladislav V. Kudryavtsev · 2011
The selforganization of statistical multiblock an d Bernoulli AB copolymers is studied. The initial ensemble is generated via the polymeranalogous reaction A →B that proceeds with the accelerating effect of neighboring B units. In a twodimensional model, th e reaction is performed in a rectangle composed of stretched chains. Then, the rectangle is closed into a cylinder, so that ring chains are located on its side sur� face. The selforganization of the ensemble is simulated via the successive rotation of each upper ring over the lower ring until arrangement with the maximum (in modulus) energy of attraction between chains is attained. Selforganization by energy is accompanied by latera l ordering: the sizes of clusters—accumulations of the onetype units—and mean heights HA (HB) of stems—columns consisting of A or B units perpendicular to chains—increase. The ratio between the values of HA, as well as HB, for ordered and initial ensembles is inde� pendent of the average composition of the system and as a rule increases as the length of blocks increases and the length of chains decreases. Features of generation of the ensemble of short chains and their ordering are revealed. It is shown that, during ordering of multiblock copolymers, the probabilistic properties (the sto� chastic behavior) of the ensemble are disturbed. The selforganization of statistical multiblock copolymers in a threedimensional model is investigated via rotation of rings in the torus of the rectangular crosssection. The effects of various factors on selforganization by energy and local ordering in 2D and 3D models are sim� ilar; however, the efficiency of ordering in the threedimensional system is always lower because, in this case, arrangements with the maximum energy of attraction simultaneously to two neighboring chains, rather than to one, are implemented for the majority of chains.