Polymer-mediated interactions and their effect on the coagulation–fragmentation of nano-colloids: a self-consistent field theory approach

Abstract

This feature paper reviews our recent efforts to theoretically model the effect of polymer mediated interactions on the coagulation-fragmentation of nano-colloids in different settings encountered in practical systems. The polymer-mediated interactions among nanoparticles play a key role in many biological and technological processes such as red blood cell aggregation, protein crystallization, self-healing of polymer composites, filler reinforcement of rubbers used in tire technology, etc. By developing and making use of the novel potential theory, we investigate several important cases of these interactions acting between nanoparticles in diverse nano-polymer composites. As a demonstration of its practical applicability, we use the developed theory to investigate the effect of polymer mediated interactions on the coagulation-fragmentation of fillers and their kinetic stability in the presence of non-adsorbing and adsorbing polymers. In particular, we use our findings to develop a pragmatic way of evaluating the kinetic stability of nano-filler agglomerates critical for understanding the filler reinforcement of rubbers. Finally, we perform thorough comparison of the present theoretical findings with the available experimental data and simulations.

Conductivity of diblock copolymer system filled with conducting nano‐particles: Effect of copolymer morphology

“…where δ(r) is the Dirac delta function, r is the distance to the filler center, and γ A,B is the adhesion energy per unit area, termed adhesion in what follows. Note that γ A,B can be measured 21,42 for a variety of polymer-filler pairs, which gives added practical convenience to the surface potential defined by Equation ( 4). It is reasonable to assume that the considered weak adsorption interactions do not significantly change the structure of the incompressible DBC in the vicinity of fillers, which significantly simplifies further derivation of W. Substituting Δw = w A À w B deduced from Equation (4) into the expression in the r.h.s.…”

Effect of the Interplay between Polymer–Filler and Filler–Filler Interactions on the Conductivity of a Filled Diblock Copolymer System

“…The coefficient ( ) of the delta function is the adhesion energy per unit area of copolymer block A ( B ) at the filler surface. is experimentally known [ 29 , 30 ] for most of the practically important polymer–filler pairs. Typically, is of the order of 10–50 mJ/m 2 .…”

Spinodal Decomposition of Filled Polymer Blends: The Role of the Osmotic Effect of Fillers

“…This feature makes it possible, in particular, to adequately describe the effect of fillers on the LCST behavior of blends that is often observed in experiments [ 3 , 4 , 6 , 7 , 8 , 9 , 33 , 34 ]. The mentioned rigorous description of the thermodynamic effects caused by the presence of fillers relies on the consistent calculation of the excess thermodynamic functions [ 35 , 36 ]. This calculation makes it possible, in particular, to consistently calculate the main, osmotic contribution to the effect of fillers on the stability of polymer blends that was omitted in the previous work.…”