Polyethylene glycol/polyurethane

Electrodeposition of glucose oxidase and bovine semm albumin on a platinum black electrode followed by glutaraldehyde cross-linking and covered with a polyethylene glycol-polyurethane outer membrane Blood glucose [38]... 

WAN 14] Wang Z., Yang Y., Burtovyy R. et al, UV-induced self-repairing polydimetltylsiloxane-polyurethane (PDMS-PUR) and polyethylene glycol-polyurethane (PEG-PUR) Cu-catalyzed networks . Journal of Materials ChemistryA, o. 2, no. 37, pp. 15527-15534,2014. 

Several polyethers are used as intermediates in the preparation of polyurethane foams whilst others such as polyethylene glycol are water soluble. 

The general molecular structure of polyether-based polyurethanes is illustrated in Fig. 25.3 a). Typical polyether sequences include polyethylene glycol and polypropylene glycol. The length of the polyether sequences between urethane links can vary from one or two ether groups up to several hundred. As the length of the polyether sequences between urethane links increases, the polymer exhibits more of the properties normally associated with polyethers. 

Polyurethanes (PU s). SL and 4,4 -diphenylmethane diisocyanate (MDI) were dissolved in tetrahydrofuran (THF), and the solution was stirred for 1 hr at 60°C. A THF solution of polyethylene glycol (PEG 400) and diethyl bis(2-hydroxyethyl)aminomethylphosphonate (polyol containing phosphorous) was added to the reaction mixture, and the reaction time was extended for 1 hr. In all reactions, the molar ratio of the total amount of isocyanate groups to the total amount of hydroxyl groups (NCO/OH) was maintained at 1.2. The lignin content in PU was 20 wt%. Each solution was drawn on a glass plate, and allowed to dry for 48 hr. The residual solvent in a sample was removed under vacuum and curing of each PU film was carried out at 120°C for 3 hr under a pressure of 50 kg/cm2. 

Elastomeric Polyurethanes from a Kraft Lignin—Polyethylene Glycol—Toluene Diisocyanate... 

Fleissman et al. (4) prepared glossy cosmetics consisting of silicone-containing polyurethanes by condensing bis-polyethylene glycol dimethicone-polypropy-lene glycol with isophorone diisocyanate. 

In our work, we calculate the equilibrium moisture from the dry and saturated mass of samples. The method was described by Thomson. We use more hydrophilic polyols, for example, hydrophiUc polyurethanes and polyethylene glycol homopolymers are used. More commonly, however, we will be using polyols from the Pluronic series of block copolymers discussed in Chapter 2. 

We have often mentioned polyethylene glycols (PEGs) related to their roles as building blocks for polyurethanes. These polymers are also well known for their protein compatibility. Adsorption was shown to be inversely related to the length of the PEG molecule. This work supported the work of Jeon discussed in Chapter 2. 

All but the polyurethane are characterized by methylene backbones with ligands that are sufficiently polar to make them water soluble. Thus, upon dissolution in water, the polarity of the water molecule associates with the polarity of the acrylic or acrylamide groups to form a shell. We discussed hydrophilic polyurethanes that are typically cross-linked and are not (but could be) considered effective thickeners. Nevertheless they too have hydration shells developed due to the influence of the polyethylene glycol backbone. The extent of that shell is determined by the hydro-philicity of the ligand the acrylic > acrylamide > alcohol > polyurethane. The volume... 

The main use of ethene oxide is as ethylene glycol, half of which is used in as anti-freeze and the other half is used in the production of polyesters. Other products are glycol ethers, polyurethanes and polyethylene glycols). We find these in many consumer products such as fibres, foils, bottles, solvents, plasticizers, adhesives, detergents, brake fluids, etc. 

Polyethylene glycol (PEG) and the very similar polyethylene oxide (PEO) are used as biocompatible coating agents and hydrogel forming materials, often as block or graft copolymers with other materials (Eig. IF). They are often bound to polyurethanes to form hydrophilic foams such as Biopol (Metabolix Inc.). 

The diisocyanates are used mainly in the manufacture of polyurethanes (PUR). These are produced by polyaddition of diisocyanates and dihydric alcohols, in particular the polyether alcohols (i.e., polyethylene glycols, polypropylene glycols, and the reaction products of propylene oxide with polyhydric alcohols). In addition, oligomeric esters from dicarboxylic acids and diols (polyester alcohols) are also used [91] ... 

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