Creation of Stable Poly(ethylene oxide) Surfaces on Poly(methyl methacrylate) Using Blends of Branched and Linear Polymers

Abstract

Thin film miscible blends of poly(methyl methacrylate) (PMMA) and a branched random copolymer of methyl methacrylate and methoxy poly(ethylene glycol) monomethacrylate, P(MMA-r-MnG), were investigated by neutron reflectivity. The branched copolymer, which has a higher surface tension than PMMA, was nevertheless found to segregate to and completely cover both the surface and silicon substrate following annealing in 2000 Å thick films with ≥2 wt % P(MMA-r-MnG). This is in contrast to linear polyethylene oxide, which was depleted at both film interfaces when blended with PMMA and annealed. The reflectivity results were confirmed by contact angle studies, which indicate that the surfaces of P(MMA-r-MnG)/PMMA blends behave like that of pure P(MMA-r-MnG), resulting in a hydrophilic surface that is stable against dissolution in water-based environments. The branched hydrophilic additive is further shown to render PMMA resistant to protein adsorption and cell adhesion.

Effect of deuterium substitution on the surface interactions in binary polymer mixtures

“…The effect of entropy on surface segregation observed here for short-branched polymers is comparable to the enthalpic contributions. It does not dominate over the enthalpic effects, as was observed recently for long-branched chain additives in the linear polymer matrix, 17,21 or for the mixtures of linear polymers with chain-length disparity. 12 Useful discussions with Drs.…”

“…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.…”

Evidence and Limits of Universal Topological Surface Segregation of Cyclic Polymers

“…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.…”

“…Both blends containing branched chains [14][15][16][17] and blends containing cyclic polymers [18] are of practical interest and the behaviors of these two sorts of topological blends are expected to be quite different. Advances in synthetic methods [35] provide means for engineering the degree to which these topological effects are important by varying not only the molecular architecture, but also the molecular weight, M.…”

Amphiphilic block copolymer/poly(dimethylsiloxane) (PDMS) blends and nanocomposites for improved fouling-release

“…In the last few years, a widely researched strategy to improve the FR properties of polymers consists of combining hydrophobic, low surface energy fluorinated moieties with hydrophilic poly(ethylene glycol) (PEG) segments in the same coating (Gudipati et al 2005;Krishnan et al 2008;Martinelli et al 2008;Grozea and Walker 2009;Park et al 2010). PEG is well known for its resistance to protein adsorption and cell adhesion (Mrksich and Whitesides 1997;Walton et al 1997;Li et al 2005).…”