Entropically driven segregation in blends of branched and linear polymers

Walton, D. G.; Mayes, Anne M.

doi:10.1103/physreve.54.2811

Cited by 67 publications

(95 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The predictions are consistent with self-consistent field theory (SCFT) simulations and neutron reflectivity (NR) results by Mayes and coworkers [14,36] and Foster and coworkers [15,17] for branched chains of varying architecture. However, this simple approach is unable to capture behaviors that can be observed in blends containing cyclic chains, which lack ends and branch points.…”

supporting

confidence: 74%

Evidence and Limits of Universal Topological Surface Segregation of Cyclic Polymers

Wang

et al. 2017

Phys. Rev. Lett.

View full text Add to dashboard Cite

supporting

confidence: 74%

Evidence and Limits of Universal Topological Surface Segregation of Cyclic Polymers

Wang

et al. 2017

Phys. Rev. Lett.

View full text Add to dashboard Cite

“…This has a wide range of implications in regards to surface tension [15,16], wall slip [17,18], the glass transition of thin films [19,20], and the effective force between polymer surfaces [21], to name a few. The phenomenon also has similar implications for mixtures of chemically identical molecules of different architecture [22][23][24][25][26].…”

Section: Introductionmentioning

confidence: 74%

Entropic segregation of short polymers to the surface of a polydisperse melt

Mahmoudi

Matsen

2017

Eur. Phys. J. E

View full text Add to dashboard Cite

Abstract.Chain ends are known to have an entropic preference for the surface of a polymer melt, which in turn is expected to cause the short chains of a polydisperse melt to segregate to the surface. Here, we examine this entropic segregation for a bidisperse melt of short and long polymers, using self-consistent field theory (SCFT). The individual polymers are modeled by discrete monomers connected by freely-jointed bonds of statistical length a, and the field is adjusted so as to produce a specified surface profile of width ξ. Semi-analytical expressions for the excess concentration of short polymers, δφ s(z), the integrated excess, θ s, and the entropic effect on the surface tension, γen, are derived and tested against the numerical SCFT. The expressions exhibit universal dependences on the molecular-weight distribution with model-dependent coefficients. In general, the coefficients have to be evaluated numerically, but they can be approximated analytically once ξ a. We illustrate how this can be used to derive a simple expression for the interfacial tension between immiscible A-and B-type polydisperse homopolymers.

show abstract

“…The restriction of configurations available to linear chains is considered to play a decisive role when the components have different lengths 12,17,18 or surface interactions. 19 Longbranched chain additives are expected 16,17,20 and observed 17,21 to segregate preferentially at surfaces of linear polymer matrix because they act 20 as a collection of unconnected short linear chains. Short-branched polymers represented by random olefinic copolymers E 1Ϫx EE x are modeled 13b, 15,22 as effective linear chains with tuned bond flexibility, or chain stiffness.…”

Section: Introductionmentioning

confidence: 97%