Macromolecules with amphiphilic monomer units at interface of two immiscible liquids

AA Glagoleva and VV Vasilevskaya, JOURNAL OF CHEMICAL PHYSICS, 147, 184902 (2017).

DOI: 10.1063/1.5001880

The adsorption of macromolecules with amphiphilic monomer units at the liquid-liquid interface was studied. The amphiphilic structure of monomer units with groups selectively interacting with alpha and beta liquids was described by the A-graft-B dumbbell model. The calculations were performed for the symmetrical interaction of A and B groups with liquids, different selectivity parameters xi and degree of polymerization N. The simulations indicate a three-step adsorption scenario, including non-adsorbed, weak and strong localization states. It was shown that the adsorption of (A-graft-B)(N) macromolecules obeys scaling laws developed to describe the adsorption of the alternating (AB)(N) copolymer at the liquid-liquid interface with critical selectivity parameter xi(c) of transition into the weak localization state depending on the degree of polymerization as N-1/5; critical selectivity parameter xi(infinity) of transition to the strong localization regime non-depending on the degree of polymerization; and relative change of perpendicular R-z radius of gyration varying as a power function of xi N-1/5: R-z(xi)/R-z(0) similar to (xi N-1/5)(rho) and rho = -2 nu/(1 - v). Meanwhile, (A-graft-B)(N) macromolecules have much lower xi(c) and xi(infinity) values and thus are more prospective for practical applications. Published by AIP Publishing.

Return to Publications page