Poly hydroxyethyl membrane

Inoue et al.1115,1161 synthesized polyvinyl/polypeptide graft copolymers by attaching branches of p-phenylazobenzyl/P-benzyl-L-aspartate (X) to poly(hydroxyethyl methacrylate) and poly(butyl methacrylate), and then prepared the corresponding membranes by casting dichloroethane solutions of the polymers. The membranes were stable in trimethylphosphate. 

Berg veld P and Reinhoudt D N 1990 Modification of ISFETs by covalent anchoring of poly(hydroxyethyl) methacrylate hydrogel. Introduction of a thermodynamically defined semiconductor-sensing membrane interface Anal. Chim. Acta 230 59-65... 

Arica M Y, Baran T, Denizli A (1999), P-Galactosidase immobilization into poly(hydroxyethyl methacrylate) membrane and performance in a continuous system ,/.4/ / /. Polym. 5 ct.,72(10), 1367-1373. 

In coated-wire electrodes (CWE) the membrane is placed directly on the electrode. The electrode can be a wire of noble metal, graphite wire, silver paste or Ag/AgCl electrode, which is the most popular solution. The role of the inner solution of ISE-s can be played in CWE-s by poli(hydroxyethyl methacrylate), polyvinyl alcohol or a hydrogel saturated with NaCl solution, placed between the electrode and the membrane. The membrane stability can be improved through addition of silver complexes to the membrane. The advantage of CWE-s over ISE-s is the possibility of cheap, mass production. The disadvantage of CWE-s is that the membrane can easily unstick from the electrode. Moreover, due to the high contact surface between the membrane and the solution, the membrane contents, i.e., the plasticizer and the ionophore, can be easily washed out into the membrane, which deteriorates the characteristics of the sensor in time. 

Arica MY, Denizli A, Salich B et al. Catalase adsorption onto Cibacron Blue F3GA and Fe(III)-derivatized poly(hydroxyethyl methacrylate) membranes and application to a continuous system. J Membr Sci 1997 129 65-76. 

BD Ratner, IF Miller. Transport through crosslinked poly(2-hydroxyethyl methacrylate) hydrogel membranes. J Biomed Mater Res 7 353-367, 1973. 

Figure 14 The reversibilities of insulin permeation through polymer membranes in a two-compartment diffusion cell AH20 ( ), AS 15 (A), AS20 ( ), H ( ). Numbers indicate the content of styrene or HEMA in feed compositions in moles. H represents a cross-linked poly(2-hydroxyethyl methacrylate) (HEMA). (From Ref. 34.)... 

S Wisniewski, SW Kim. Permeation of water-soluble solutes through poly(2-hydroxyethyl methacrylate) and poly(2-hydroxyethyl methacrylate) crosslinked with ethylene glycol dimethacrylate. J Membrane Sci 6 299-308, 1980. 

Anderson, J. M., Komis, T., Nelson, T., Horst, M., and Love, D. S., The Slow Release of Hydrocortisone Sodium Succinate from Poly(2-Hydroxyethyl Methacrylate) Membranes, in Hydrogels for Medical and Related Applications (J. D. Andrade, Ed.), American Chemical Society Washington, pp. 167-178. 1976. 

As a result, zones A, B, and C have comparatively a basic, neutral, and acidic character, respectively. Increasing the DC electric current leads to the overall acidification of the gel sample (see Fig. 6, curve 4) due to the easy ionization of the acidic groups. Consequently, this narrows the zones B and C and expands zone A. Polybetaine hydrogel membranes of isopropyl-2-[2 -(trimethylammonium)ethyl phosphoryl] ethyl fumaramate and 2-hydroxyethyl methacrylate effectively enhance the water content in comparison with poly(2-hydroxyethyl methacrylate) [224]. The content of water in hydrogel membranes increases, but the amount of adsorbed BSA decreases with the increase of the betaine content in the feed. The values of the tensile strength and tensile elongation of the hydrogel reach 68.4 g mm and 239%, respectively. 

It is on the basis of Lovrien s ideas concerning the photoregulation of polymer conformation in solution by means of photochromic species that Van der Veen Prins reported a first photomechanochemical model transducer, consisting of water-swollen membranes of poly(2-hydroxyethyl methacrylate) cross-linked with ethylene glycol dimethacrylate (1.1 wt-%) in the presence of a sulfonated bis-azostilbene dye (chry-sophenine G), the ratio chrysophenine/2-hydroxyethyl methacrylate being 1/400. 

The membranes of the thermosensitive controlled-release microcapsules were constructed by a random mixing Aquacoat (Table 1) with the latex particles having poly(EA/MMA/2-hydroxyethyl methacrylate) core and poly(A-isopropylacrylamide (NIPAAm)) shell. This is an example where the membrane has the random two-phase structure as shown in Fig. 5. The microcapsules exhibited a thermosensitive release of water-soluble drug. The mechanism is explained in Fig. 6. When the temperature was changed in a stepwise manner between 30 and 50°C, the microcapsules showed an on-off pulsatile release. This on-off response was reversible. 

Phosphite-functionalized polymers were prepared by llthlatlon of brominated poly(styrene-DVB) membranes or beads followed by hydroxyethylation with ethylene oxide and phosphitation with chlorodlalkylphosphlte and a base dlmethylanillne was found to be most suitable (22). Dlmethylanillne hydrochloride, which is formed in the reaction, is highly soluble in chloroform and thus can be conveniently removed without the need for a more polar solvent which may cause solvolysis of the attached... 

Cylindrical structures of finite thickness were consistent with the small angle light scattering (SALS) data obtained on hydrated poly(2-hydroxyethyl methacrylate), a polymer similar to those used for reverse osmosis membranes ( ). 

Many approaches have been developed for the production of ionic liquid-polymer composite membranes. For example, Doyle et al. [165] prepared RTILs/PFSA composite membranes by swelling the Nafion with ionic liquids. When 1-butyl, 3-methyl imidazolium trifluoromethane sulfonate was used as the ionic liquid, the ionic conductivity ofthe composite membrane exceeded 0.1 S cm at 180 °C. A comparison between the ionic liquid-swollen membrane and the liquid itself indicated substantial proton mobility in these composites. Fuller et al. [166] prepared ionic liquid-polymer gel electrolytes by blending hydrophilic RTILs into a poly(vinylidene fiuoridej-hexafluoropropylene copolymer [PVdF(HFP)] matrix. The gel electrolytes prepared with an ionic liquid PVdF(HFP) mass ratio of 2 1 exhibited ionic conductivities >10 Scm at room temperature, and >10 Scm at 100 °C. When Noda and Watanabe [167] investigated the in situ polymerization of vinyl monomers in the RTILs, they produced suitable vinyl monomers that provided transparent, mechanically strong and highly conductive polymer electrolyte films. As an example, a 2-hydroxyethyl methacrylate network polymer in which BPBF4 was dissolved exhibited an ionic conductivity of 10 S cm at 30 °C. 

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