The behavior analysis of the mixture of two oppositely charged polyelectrolytes with the help of a macroscopic mechanical system

To realize the idea of imitation modelling proposed by us recently, a mechanical system consisting of identical quantity of two types springs (20 ones of each type) having different elasticities and equilibrium lengths, was fabricated. To mimic a polymer network, all springs should be connected in such a manner that a quadrangular lattice will formed, in doing so each node of this lattice should contain two springs of each type. As a result of such restriction, the springs of one type form chains at any allowable spring distribution, and these chains can be considered as "polymer macromolecules". Each random system configuration generated by computer, was assembled inside of metallic frame and photographed with further analysis with the help of the computer program including pattern recognition, image analysis. As a result, the system parameters (energy and order parameter) were calculated and collected for 256 generated configurations, differed by system orientational ordering when more springs of the one type are orientated along one direction (for example, along x-axis), whereas the orientation along other direction (along y-axis) is preferable for the other type springs. The statistical analysis of obtained data allows one to derive the dependence of the system energy vs. spatial distribution of the system springs (more exactly, their orientational ordering). Using the obtained dependence, the statistical weight of each system state characterized by energy and orientation ordering, can be calculated (more exactly, the state portion corresponding to a narrow range of the above system parameters). Thereafter the system entropy as well as the free energy can be introduced, and the minimum of last corresponds to the system equilibrium state. The above examining allows one to verify experimentally the outcomes of theoretical model analyzing the self-ordering in a 2D two-component system modelling the behavior of a mixture of two oppositely charged polyelectrolytes.