Fluorocarbon Surfactant Polymers:  Effect of Perfluorocarbon Branch Density on Surface Active Properties

Abstract

We describe a series of fluorocarbon surfactant polymers designed for modifying fluorocarbon surfaces such as poly(tetrafluoroethylene). Novel fluorocarbon surfactant polymers poly(Nvinyldextranaldonamide-co-N-vinylperfluoroundecanamide), in which hydrophilic dextran oligosaccharides and hydrophobic perfluoroundecanoyl groups were incorporated sequentially onto a poly(vinylamine) backbone, were synthesized and characterized by FT-IR, NMR, and XPS spectroscopy. By adjusting the feed ratio of dextran to fluorocarbon branches, surfactant polymers with different hydrophilic/hydrophobic balances were prepared. The surface activity of the surfactants at the air/water interface was demonstrated by significant reductions in water surface tension. Surfactant adsorption and adhesion at the solid PTFE/aqueous interface were examined under well-defined dynamic flow conditions, using a rotating disk system. The surface activity at the air/water interface and adhesion stability on PTFE under an applied shear stress both increase with increasing density of fluorocarbon branches on the polymer backbone. The results show that stable surfactant adhesion on PTFE can be achieved by adjusting the hydrophilic dextran to hydrophobic fluorocarbon branch ratio.

Biomimetic Fluorocarbon Surfactant Polymers Reduce Platelet Adhesion on PTFE/ePTFE Surfaces

“…We examined the fluorocarbon surfactant polymer adhesion stability on PTFE using XPS under dynamic flow conditions in PBS in a previous report [28]. In this report, we further tested the surfactant polymer stability on PTFE under dynamic shear conditions with fluorescence microscopy.…”

“…The synthesis and characterization of fluorocarbon surfactant polymers were described in a previous report [28]. Briefly, the fluorocarbon surfactant polymers were synthesized by sequential attachment of dextran and perfluoroundecanoyl branches to the poly(vinyl amine) backbone.…”

“…Briefly, the fluorocarbon surfactant polymers were synthesized by sequential attachment of dextran and perfluoroundecanoyl branches to the poly(vinyl amine) backbone. The dextran percentage in the fluorocarbon surfactant polymers was kept constant at 22 mol%, whereas the percentage of fluorocarbon branches varied from 15 to 45 mol% [28]. The fluorocarbon surfactant polymers were designated as PVAm(Dex:FC11) 1:0.5, 1:1 or 1:2, according to the ratio of dextran to perfluoroundecanoyl side-chains in the polymer structure (Fig.…”

“…The disks were then subjected to PBS or whole blood in the rotating disk (RD) apparatus under dynamic shear and imaged again with the same objective and microscope setting to determine the post-exposure fluorescence intensity. The set up of the rotating disk system (RDS) was described previously [28, 30]. …”

“…However, the hydrocarbon surfactant polymers do not have strong affinity to the PTFE surface. To address this problem, surfactant polymers with fluorocarbon branches have been designed to increase the adhesion between surfactant polymer and PTFE [28]. The fluorocarbon surfactant polymers described here are based on poly(vinyl amine) with pendent hydrophilic dextran and hydrophobic perfluoroundecanoyl branches (Fig.…”