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HYDROXYETHYL COPOLYMER

The use of hydroxyethyl (also hydroxypropyl) methacrylate as a monomer permits the introduction of reactive hydroxyl groups into the copolymers. This offers the possibility for subsequent cross-linking with an HO-reactive difunctional agent (diisocyanate, diepoxide, or melamine-formaldehyde resin). Hydroxyl groups promote adhesion to polar substrates. [Pg.1013]

COLORANTSFORFOOD,DRUGS,COSPffiTICSANDPffiDICALDEVICES] (Void) Poly(hydroxyethyl methacrylate)-dye copolymers... [Pg.786]

The simplest monomer, ethylenesulfonic acid, is made by elimination from sodium hydroxyethyl sulfonate and polyphosphoric acid. Ethylenesulfonic acid is readily polymerized alone or can be incorporated as a copolymer using such monomers as acrylamide, aHyl acrylamide, sodium acrylate, acrylonitrile, methylacrylic acid, and vinyl acetate (222). Styrene and isobutene fail to copolymerize with ethylene sulfonic acid. [Pg.83]

Emulsion polymerizations of vinyl acetate in the presence of ethylene oxide- or propylene oxide-based surfactants and protective coUoids also are characterized by the formation of graft copolymers of vinyl acetate on these materials. This was also observed in mixed systems of hydroxyethyl cellulose and nonylphenol ethoxylates. The oxyethylene chain groups supply the specific site of transfer (111). The concentration of insoluble (grafted) polymer decreases with increase in surfactant ratio, and (max) is observed at an ethoxylation degree of 8 (112). [Pg.466]

In contrast to the situation with high sohds coatings, acryhc resins are, in general, more appropriate than polyesters for water-reducible baking coatings. Acryhc copolymers using acryhc acid (2-propenoic acid) [79-10-7], (see Acrylic acid and derivatives) and 2-hydroxyethyl methacrylate as... [Pg.338]

Poly(hydroxyethyl methacrylate)-dye copolymers —The color additives formed by reaction of one or more of the foUowiag reactive dyes with poly(hydroxyethyl methacrylate), so that the sulfate group (or groups) or chlorine substituent of the dye is replaced by an ether linkage to poly(hydroxyethyl methacrylate) (see Dyes, reactive). The dyes that may be used alone or ia combination are... [Pg.453]

Among the pairs of monomers used in synthesizing block copolymers by this method are MMA/AN, C2F4/ MMA, and HEMA/DMA (HEMA = hydroxyethyl methacrylate and DMA = decyl methacrylate). [Pg.254]

Dielectric relaxation measurements of polyethylene grafted with acrylic acid(AA), 2-hydroxyethyl methacrylate (HEMA) and their binary mixture were carried out in a trial to explore the molecular dynamics of the grafted samples [125]. Such measurements provide information about their molecular packing and interaction. It was possible to predict that the binary mixture used yields a random copolymer PE—g—P(AA/HEMA), which is greatly enriched with HEMA. This method of characterization is very interesting and is going to be developed in different polymer/monomer systems. [Pg.512]

Chemically attached copolymers of iV-vinylpyrrolidone (N-VP) and N-(2-hydroxyethyl)acrylamide (N-HEAA) steeply decrease the inherent glass adsorp-tivity which is observed for proteins in aqueous buffer solutions. Thus, it became possible to apply the prepared materials to the size exclusion chromatography of viruses and ribosomes. [Pg.154]

Indeed, the polymeric interface seems to be highly diffuse and hydrophilic because copolymers of N-vinylpyrrolidone and N- (2-hydroxyethyl) acrylamide are readily soluble in water [53]. Besides, aminopropyl-glass adsorbs the acryloyl chloride copolymer so that only 10% of its active functions become amidated. The rest is located on the loops and tails of the attached macromolecules [51]. Thus the steric repulsion of the bonded phase is a probable reason for the high inertness of the packing towards viruses. [Pg.154]

ABA type poly(hydroxyethyl methacrylate) (HEMA) and PDMS copolymers were synthesized by the coupling reactions of preformed a,co-isocyanate terminated PDMS oligomers and amine-terminated HEMA macromonomers312). Polymerization reactions were conducted in DMF solution at 0 °C. Products were purified by precipitation in diethyl ether to remove unreacted PDMS oligomers. After dissolving in DMF/toluene mixture, copolymers were reprecipitated in methanol/water mixture to remove unreacted HEMA oligomers. Microphase separated structures were observed under transmission electron microscope, using osmium tetroxide stained thin copolymer films. [Pg.45]

Implants in the rabbit corneas exhibited no observable inflammatory characteristics over a period of 6 weeks. Compared to other previously tested polymers, the inertness of these polyanhydrides rivals that of the biocompatible poly(hydroxyethyl methacrylate) and ethylene-vinyl acetate copolymer. Histological examination of the removed corneas also revealed the absence of inflammatory cells (21)... [Pg.66]

One-to-one random copolymers of acrylic acid with either hydroxyethyl acrylate (a hydrogel model) or methyl acrylate failed to protect insulin from release under gastric conditions (Figure 6). In the case of the hydrogel, the expected swelling due to exposure to water occurred, releasing insulin. The behavior of the ester copolymer led to the prediction that there should be no more than about four carbon atoms per carboxylic acid group in a repeat unit of the polymers. We have not been able to disprove this hypothesis thus far. [Pg.222]

Figure 6. Release of insulin under gastric conditions from crosslinked 1/1 random acrylic acid copolymers with either hydroxyethyl acrylate or methyl acrylate. Figure 6. Release of insulin under gastric conditions from crosslinked 1/1 random acrylic acid copolymers with either hydroxyethyl acrylate or methyl acrylate.
Fluid loss additives such as solid particles and water-thickening polymers may be added to the drilling mud to reduce fluid loss from the well bore to the formation. Insoluble and partially soluble fluid loss additives include bentonite and other clays, starch from various sources, crushed walnut hulls, lignite treated with caustic or amines, resins of various types, gilsonite, benzoic acid flakes, and carefully sized particles of calcium borate, sodium borate, and mica. Soluble fluid loss additives include carboxymethyl cellulose (CMC), low molecular weight hydroxyethyl cellulose (HEC), carboxy-methYlhydroxyethyl cellulose (CMHEC), and sodium acrylate. A large number of water-soluble vinyl copolymers and terpolymers have been described as fluid loss additives for drilling and completion fluids in the patent literature. However, relatively few appear to be used in field operations. [Pg.10]

Controlling fluid loss loss is particularly important in the case of the expensive high density brine completion fluids. While copolymers and terpolymers of vinyl monomers such as sodium poly(2-acrylamido-2-methylpropanesulfonate-co-N,N-dimethylacrylamide-coacrylic acid) has been used (H)), hydroxyethyl cellulose is the most commonly used fluid loss additive (11). It is difficult to get most polymers to hydrate in these brines (which may contain less than 50% wt. water). The treatment of HEC particle surfaces with aldehydes such as glyoxal can delay hydration until the HEC particles are well dispersed (12). Slurries in low viscosity oils (13) and alcohols have been used to disperse HEC particles prior to their addition to high density brines. This and the use of hot brines has been found to aid HEC dissolution. Wetting agents such as sulfosuccinate diesters have been found to result in increased permeability in cores invaded by high density brines (14). [Pg.11]

High fluid injection rates are often required. For this reason, friction reducers are often used in acid fracturing. These include polyacrylamide and acrylamide copolymers, guar gum, hydroxyethyl cellulose, and karaya gum (108)... [Pg.21]

The enzymatic polymerization of lactones could be initiated at the hydroxy group of the polymer, which expanded to enzymatic synthesis of graft copolymers. The polymerization of c-CL using thermophilic lipase as catalyst in the presence of hydroxyethyl cellulose (HEC) film produced HEC-gra/f-poly( -CL) with degree of substitution from 0.10 to 0.32 [102]. [Pg.253]

A combination of ATRP and ROP was employed for the synthesis of PLLA-fr-PS block copolymers and PLLA-fr-PS-fo-PMMA triblock terpoly-mers [120]. Styrene was initially polymerized using the functional initiator /3-hydroxyethyl a-bromobutyrate, HEBB, and the catalytic system CuBr/bpy. [Pg.63]

Thiol end-functionalized poly(2-hydroxyethyl methacrylate-g-ethylene glycol) graft copolymers were synthesized by ATRP copolymerization of... [Pg.117]

Polymeric particles can be constructed from a number of different monomers or copolymer combinations. Some of the more common ones include polystyrene (traditional latex particles), poly(styrene/divinylbenzene) copolymers, poly(styrene/acrylate) copolymers, polymethylmethacrylate (PMMA), poly(hydroxyethyl methacrylate) (pHEMA), poly(vinyltoluene), poly(styrene/butadiene) copolymers, and poly(styrene/vinyltoluene) copolymers. In addition, by mixing into the polymerization reaction combinations of functional monomers, one can create reactive or functional groups on the particle surface for subsequent coupling to affinity ligands. One example of this is a poly(styrene/acrylate) copolymer particle, which creates carboxylate groups within the polymer structure, the number of which is dependent on the ratio of monomers used in the polymerization process. [Pg.583]

Chang, M., Colvin, M., and Rembaum, A. (1986) Acrolein and 2-hydroxyethyl methacrylate copolymer microspheres. /. Polym. Sci. Part C Polym. Lett. 24, 603-606. [Pg.1053]

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. [Pg.185]


See other pages where HYDROXYETHYL COPOLYMER is mentioned: [Pg.421]    [Pg.58]    [Pg.196]    [Pg.42]    [Pg.164]    [Pg.440]    [Pg.489]    [Pg.490]    [Pg.198]    [Pg.647]    [Pg.170]    [Pg.539]    [Pg.586]    [Pg.29]    [Pg.174]    [Pg.294]    [Pg.477]    [Pg.491]    [Pg.21]    [Pg.34]    [Pg.82]    [Pg.130]    [Pg.195]    [Pg.264]    [Pg.96]    [Pg.105]   
See also in sourсe #XX -- [ Pg.10 , Pg.43 , Pg.51 , Pg.91 ]

See also in sourсe #XX -- [ Pg.46 ]




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Hydroxyethylation

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