Surface Interaction Parameter Measurement of Solvated Polymers via Model End-Tethered Chains

Abstract

We present a method for the direct measurement of the relative energy of interaction between a solvated polymer and a solid interface. By tethering linear chains covalently to the surface, we ensured the idealized and constant configuration of polymer molecules for measurement, modeling, and parameter estimation. For the case of amine-terminated polystyrene bound to a glycidoxypropyl silane film submerged in cyclohexane-d12, we estimated the χ parameter for the temperature range 10.7 °C to 52.0 °C, and found a downward sloping trend that crosses the χ = 0.5 threshold at 37 °C to 40 °C, in agreement with solution estimates for the same system. We simultaneously estimated the surface interaction parameter χs at each temperature, finding a decreasing affinity of the chains for the surface with increasing temperature, consistent with empirical observations. The theoretical model shows some limitations in a stronger solvent (toluene-d8) that prevent rigorous parameter estimation, but we demonstrate a qualitative change in χ and χs towards stronger solvency and weaker surface interaction with increasing temperature.

Approximate Corona Phase Hamiltonian for Individual Cylindrical Nanoparticle–Polymer Interactions

“…Monte Carlo simulations have been used to develop phase diagrams for homopolymer adsorption to spherical surfaces, where the extent of adsorption and the resulting configurations are governed by the spherical radius. Configurations on ellipsoidal and cylindrical surfaces have been predicted using worm-like chain models and coarse-grained bead-and-spring models , and through energetic scaling analysis, self-consistent field theory simulations, and experiments . Further, the conformational reconfiguration or desorption from these surfaces brought about by external chemical, electrical, or thermal stimuli is also important for understanding how particles interact for nanoparticle drug delivery, carbon nanotube–polymer composites, and organic solar cells .…”

Nanostructure Explains the Behavior of Slippery Covalently Attached Liquid Surfaces

“…From this NR signal, the surface‐normal density profile of the interface averaged over several cm 2 (Figure 4b) can be extracted through a model‐optimization process; here a previously documented freeform approach was used with no a priori assumptions regarding layer structure [19] . To interpret the derived profiles and extract information regarding $${\hat N_{\rm{n}} }$$ and PDI, numerical self‐consistent field theory (nSCFT) [30,31,32,33] was used. For a given molecular weight distribution, nSCFT produces a volume fraction profile, which can be directly compared to NR output.…”

“…Chemie field theory (nSCFT) [30,31,32,33] was used. For a given molecular weight distribution, nSCFT produces a volume fraction profile, which can be directly compared to NR output.…”

Nanostructure Explains the Behavior of Slippery Covalently Attached Liquid Surfaces

“…Chemie Forschungsartikel field theory (nSCFT) [30,31,32,33] was used. For a given molecular weight distribution, nSCFT produces a volume fraction profile, which can be directly compared to NR output.…”