Polyethylene oxide surfaces

Lee JH, Lee HB, Andrade JD (1995) Blood compatibility of polyethylene oxide surfaces. Progr Polymer Sci 20 1043-1079... 

Unsworth, L.D., Sheardown, H., and Brash, J.L. 2005. Polyethylene oxide surfaces of variable chain density by chemisorption of PEO-thiol on gold Adsorption of proteins from plasma studied by radiolabelhng and immunoblotting. Biomaterials 26 5927-5933. 

Ebert M, Ward B, Anderson J, McVenes R, Stokes K. In vivo biostabUity of polyether polyurethanes with polyethylene oxide surface-modifying end groups resistance to biologic oxidation and stress cracking. J Biomed Mater Res A 2005 75(l) 175-84. 

Ward R, Anderson J, McVenes R, et al. (2007) In vivo biostability of polyether polyurethanes with fluoropolymer and polyethylene oxide surface modifying endgroups resistance to metal ion oxidation. J Biomed Mater Res 80 (1) 34 4. 

The qualitative thermodynamic explanation of the shielding effect produced by the bound neutral water-soluble polymers was summarized by Andrade et al. [2] who studied the interaction of blood with polyethylene oxide (PEO) attached to the surfaces of solids. According to their concept, one possible component of the passivity may be the low interfacial free energy (ysl) of water-soluble polymers and their gels. As estimated by Matsunaga and Ikada [3], it is 3.7 and 3.1 mJ/m2 for cellulose and polyvinylalcohol whereas 52.6 and 41.9 mJ/m2 for polyethylene and Nylon 11, respectively. Ikada et al. [4] also found that adsorption of serum albumin increases dramatically with the increase of interfacial free energy of the polymer contacting the protein solution. 

In the presence of polyethylene oxide MW 300,000 at a concentration of 0.025 g liter , variations in pH and ionic strength have no effect on elution volumes and a single calibration curve is obtained as shown in Figure 4 and Table II. This behavior presumably also results from modification of the glass surface by the polyethylene oxide surfactant, but in this case charge effects appear to be completely suppressed and the effective pore diameter and volume reduced. Such an interpretation is also in accord with the fact that the elution voliomes are lower with polyethylene oxide than with Tergitol, since Tergitol is a much smaller molecule than the polyethylene oxide. 

Nonvolatile compounds cannot be analysed unless pyrolysis or derivatisation converts them to a condition amenable to GC. Derivatisation GC (or LC) has been used for several components such as erucamide (imidi-sation for volatility), fatty amines (aromatic amidation for UV detectability), and polyethylene oxides (esterification for both volatility and detectability) [178]. The surface concentration of erucamide on extruded LLDPE films was determined quantitatively by surface washings with ether, followed by evaporation, dissolution... 

Fig. 8. Adsorption of BSA on surfaces coated with polyethylene oxide (PEO). Influence of the grafting density of PEO at the surface for different polymer chain lengths (---700,-------- 445, and------148 ethylene oxide monomers) on the...

Several experimental parameters have been used to describe the conformation of a polymer adsorbed at the solid-solution interface these include the thickness of the adsorbed layer (photon correlation spectroscopy(J ) (p.c.s.), small angle neutron scattering (2) (s.a.n.s.), ellipsometry (3) and force-distance measurements between adsorbed layers (A), and the surface bound fraction (e.s.r. (5), n.m.r. ( 6), calorimetry (7) and i.r. (8)). However, it is very difficult to describe the adsorbed layer with a single parameter and ideally the segment density profile of the adsorbed chain is required. Recently s.a.n.s. (9) has been used to obtain segment density profiles for polyethylene oxide (PEO) and partially hydrolysed polyvinyl alcohol adsorbed on polystyrene latex. For PEO, two types of system were examined one where the chains were terminally-anchored and the other where the polymer was physically adsorbed from solution. The profiles for these two... 

A new class of amphiphilic, surface-active graft copolymers, hydrophobically modified hydroxyethyl celluloses (HM-HEC s), are comprised of a cellulose backbone with short polyethylene oxide (PEO) and grafted alkyl side chains. They are excellent steric stabilizers of 0/W emulsions. 

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