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Hydroxypropylation

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]

Limitations with the chiral selectivity of the native cyclodextrins fostered the development of various functionalized cyclodextrin-based chiral stationary phases, including acetylated (82,83), sulfated (84), 2-hydroxypropyl (85), 3,5-dimethylphenylcarbamoylated (86) and... [Pg.65]

The derivatives are hydroxyethyl and hydroxypropyl cellulose. AH four derivatives find numerous appHcations and there are other reactants that can be added to ceUulose, including the mixed addition of reactants lea ding to adducts of commercial significance. In the commercial production of mixed ethers there are economic factors to consider that include the efficiency of adduct additions (ca 40%), waste product disposal, and the method of product recovery and drying on a commercial scale. The products produced by equation 2 require heat and produce NaCl, a corrosive by-product, with each mole of adduct added. These products are produced by a paste process and require corrosion-resistant production units. The oxirane additions (eq. 3) are exothermic, and with the explosive nature of the oxiranes, require a dispersion diluent in their synthesis (see Cellulose ethers). [Pg.314]

Hydroxyethyi and 2-hydroxypropyl acrylates are prepared by the addition of ethylene oxide or propylene oxide to acryhc acid (104,105). [Pg.156]

Selected physical properties of various methacrylate esters, amides, and derivatives are given in Tables 1—4. Tables 3 and 4 describe more commercially available methacrylic acid derivatives. A2eotrope data for MMA are shown in Table 5 (8). The solubiUty of MMA in water at 25°C is 1.5%. Water solubiUty of longer alkyl methacrylates ranges from slight to insoluble. Some functionalized esters such as 2-dimethylaniinoethyl methacrylate are miscible and/or hydrolyze. The solubiUty of 2-hydroxypropyl methacrylate in water at 25°C is 13%. Vapor—Hquid equiUbrium (VLE) data have been pubHshed on methanol, methyl methacrylate, and methacrylic acid pairs (9), as have solubiUty data for this ternary system (10). VLE data are also available for methyl methacrylate, methacrylic acid, methyl a-hydroxyisobutyrate, methanol, and water, which are the critical components obtained in the commercially important acetone cyanohydrin route to methyl methacrylate (11). [Pg.242]

A ceUulose ether thickener such as hydroxypropyl methylceUulose can be added to thicken a methylene chloride remover. Removers that are acid or alkaline activated requite thickeners that wid not be hydroly2ed by the acid or the base. [Pg.551]

Guar gum is a nonionic, branched-chain polysaccharide, a galactomaiman that is usually hydroxypropylated for use in drilling (52). It produces viscous solutions in fresh or salt water at concentrations of ca 3—6 kg/m (1—2 lb /bbl). It is used in soHds-free and low soflds muds and degrades rapidly above 80°C, limiting its use to shallow wells. [Pg.179]

Under alkaline conditions, an amine addition reaction can occur. For example, in the reaction of C3H3CH2CH2NH2 and aEyl alcohol in the presence of sodium alcoholate at 108°C for 80 h, 43.4% A/-(3-hydroxypropyl)phenylethylamine is formed (12). [Pg.72]

A/-(2-hydroxypropyl)-dodecanamide [142-54-1] Ninol AD31 Stepan flakes... [Pg.185]

Ethoxylation and Propoxylation. Ethylene oxide [75-21-8] or propylene oxide [75-56-9] add readily to primary fatty amines to form bis(2-hydroxyethyl) or bis(2-hydroxypropyl) tertiary amines secondary amines also react with ethylene or propylene oxide to form 2-hydroxyalkyl tertiary amines (1,3,7,33—36). The initial addition is completed at approximately 170°C. Additional ethylene or propylene oxide can be added by using a basic catalyst, usually sodium or potassium hydroxide. [Pg.219]

The addition of a 3-hydroxypropyl group to the 7 -position of fortimicin A caused a significant reduction in antibacterial activity (237). [Pg.485]

Hydrogen Sulfide andMercaptans. Hydrogen sulfide and propylene oxide react to produce l-mercapto-2-propanol and bis(2-hydroxypropyl) sulfide (69,70). Reaction of the epoxide with mercaptans yields 1-aLkylthio- or l-arylthio-2-propanol when basic catalysis is used (71). Acid catalysts produce a mixture of primary and secondary hydroxy products, but ia low yield (72). Suitable catalysts iaclude sodium hydroxide, sodium salts of the mercaptan, tetraaLkylammonium hydroxide, acidic 2eohtes, and sodium salts of an alkoxylated alcohol or mercaptan (26,69,70,73,74). [Pg.135]

In industrial production of acid-modified starches, a 40% slurry of normal com starch or waxy maize starch is acidified with hydrochloric or sulfuric acid at 25—55°C. Reaction time is controlled by measuring loss of viscosity and may vary from 6 to 24 hs. For product reproducibiUty, it is necessary to strictly control the type of starch, its concentration, the type of acid and its concentration, the temperature, and time of reaction. Viscosity is plotted versus time, and when the desired amount of thinning is attained the mixture is neutralized with soda ash or dilute sodium hydroxide. The acid-modified starch is then filtered and dried. If the starch is washed with a nonaqueous solvent (89), gelling time is reduced, but such drying is seldom used. Acid treatment may be used in conjunction with preparation of starch ethers (90), cationic starches, or cross-linked starches. Acid treatment of 34 different rice starches has been reported (91), as well as acidic hydrolysis of wheat and com starches followed by hydroxypropylation for the purpose of preparing thin-hoiling and nongelling adhesives (92). [Pg.344]

L-pyrenyldiazomethane to form stable, highly fluorescent L-pyrenyhnethyl monoesters (87). These esters have been analy2ed in human blood by ce combined with lif detection. To mimini e solute adsorption to the capillary wall, they were coated with polyacrjiamide, and hydroxypropyl methylceUulose and dimethylfoTTnamide were used as buffer additives to achieve reflable separations. Separation was performed in tris-citrate buffer, pH 6.4, under reversed polarity conditions. The assay was linear for semm MMA concentrations in the range of 0.1—200 p.mol/L. [Pg.247]

Cationic poly(vinyl alcohol) has been prepared by the reaction of A/-(3-chloro-2-hydroxypropyl)-Ai,Ai,A/-trimethylammonium chloride, PVA, and sodium hydroxide (143). Reactions between alkyUdene epoxide and PVA in particulate, free-flowing form in an alkaline environment have been reported (144). [Pg.481]

Etherification. Carbohydrates are involved in ether formation, both intramoleculady and intermoleculady (1,13). The cycHc ether, 1,4-sorbitan, an 1,4-anhydroalditol, has already been mentioned. 3,6-Anhydro-a-D-galactopyranosyl units are principal monomer units of the carrageenans. Methyl, ethyl, carboxymethyl, hydroxyethyl, and hydroxypropyl ethers of cellulose (qv) are all commercial materials. The principal starch ethers are the hydroxyethyl and hydroxypropylethers (see Cellulose ethers Starch). [Pg.481]

MethylceUulose is made by reaction of alkaU ceUulose with methyl chloride until the DS reaches 1.1—2.2. HydroxypropyhnethylceUulose [9004-65-3], the most common of this family of products, is made by using propylene oxide in addition to methyl chloride in the reaction MS values of the hydroxypropyl group in commercial products are 0.02—0.3. Use of 1,2-butylene oxide in the alkylation reaction mixture gives hydroxybutyhnethylceUulose [9041-56-9, 37228-15-2] (MS 0.04—0.11). HydroxyethyhnethylceUulose [903242-2] is made with ethylene oxide in the reaction mixture. [Pg.489]

The abihty to moisturize the stratum corneum has also been claimed for the presence of certain hydrophilic polymers, for example, guar hydroxypropyl trimonium chloride [65497-29-2] on the skin. By far the most popular way to moisturize skin is with humectants, some of which are Hsted in Table 12. It is claimed that humectants attract water from the environment and thereby provide moisture to the skin. [Pg.296]


See other pages where Hydroxypropylation is mentioned: [Pg.465]    [Pg.112]    [Pg.200]    [Pg.322]    [Pg.457]    [Pg.501]    [Pg.501]    [Pg.501]    [Pg.501]    [Pg.501]    [Pg.501]    [Pg.501]    [Pg.501]    [Pg.501]    [Pg.501]    [Pg.901]    [Pg.976]    [Pg.1025]    [Pg.65]    [Pg.430]    [Pg.435]    [Pg.243]    [Pg.243]    [Pg.245]    [Pg.263]    [Pg.181]    [Pg.376]    [Pg.346]    [Pg.444]    [Pg.485]    [Pg.488]    [Pg.272]    [Pg.73]   
See also in sourсe #XX -- [ Pg.457 , Pg.560 , Pg.631 , Pg.736 , Pg.748 , Pg.759 ]

See also in sourсe #XX -- [ Pg.226 ]

See also in sourсe #XX -- [ Pg.226 ]

See also in sourсe #XX -- [ Pg.402 ]




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1-Allyloxy-2-hydroxypropyl sulfonic acid

2- hydroxypropyl phosphate

2-Hydroxypropyl methacrylate

2-Hydroxypropyl p-nitrophenyl

2-Hydroxypropyl p-nitrophenyl phosphate

2-hydroxypropyl 4-nitrophenyl phosphate

2-hydroxypropyl 4-nitrophenyl phosphate HPNP) transesterification

2-hydroxypropyl methacrylate, chemical

2-hydroxypropyl phosphates, hydrolysis

3- Hydroxypropyl ethers

3- chloro-2-hydroxypropyl

3- hydroxypropyl methyl

3-Amino-2-hydroxypropyl-substituted

4-hydroxypropyl

Acetic acid Hydroxypropyl cellulose

Acetyl/hydroxypropyl groups

Acetylene, 7-hydroxypropyl

Acetylene, diphenyl 7-hydroxypropyl

Aqueous hydroxypropyl cellulose

Aqueous hydroxypropyl cellulose solutions

Carboxymethyl-hydroxypropyl guar

Carboxymethyl-hydroxypropyl guar CMHPG)

Cellulose 2-hydroxypropyl methyl ether, acetate

Cellulose Hydroxypropyl methylcellulose

Cellulose hydroxypropyl ether

Cellulose hydroxypropyl methyl ether

Cellulose phthalate hydroxypropyl methyl

Cellulose phthalate hydroxypropyl methyl ether

Cellulose-based polymers hydroxypropyl methylcellulose

Coating agents hydroxypropyl cellulose

Cyclohexa-1,3-diene5-carboxylate 3-hydroxypropyl-2-ethyl

Disintegrants, hydroxypropyl starch

Epichlorohydrin, crosslinked with hydroxypropyl)starch

Ethoxycarbonyl-4-(3-hydroxypropyl)-1-methylpyrrole

Excipient hydroxypropyl methylcellulose

HPMC hydroxypropyl methylcellulose

HYDROXYPROPYL COPOLYMER

HYDROXYPROPYL METHACRYLAMIDE

Hydroxypropyl 2-ethylcyclohexa-1,3-diene-5-carboxylate

Hydroxypropyl Alginate

Hydroxypropyl Distarch Phosphate

Hydroxypropyl Starch

Hydroxypropyl acetate succinate

Hydroxypropyl acrylate

Hydroxypropyl beta-cyclodextrin

Hydroxypropyl cellulose

Hydroxypropyl cellulose (HPC

Hydroxypropyl cellulose drug release

Hydroxypropyl cellulose films

Hydroxypropyl cellulose films, extruded

Hydroxypropyl cellulose gelling agents

Hydroxypropyl cellulose low-substituted

Hydroxypropyl cellulose macromolecules

Hydroxypropyl cellulose solubility

Hydroxypropyl cellulose stability

Hydroxypropyl ether of cellulose

Hydroxypropyl guar

Hydroxypropyl lignin

Hydroxypropyl methacrylate HPMA)

Hydroxypropyl methacrylate polymer

Hydroxypropyl methyl cellulose

Hydroxypropyl methyl cellulose HPMC)

Hydroxypropyl methylcellulose

Hydroxypropyl methylcellulose -based

Hydroxypropyl methylcellulose applications

Hydroxypropyl methylcellulose drug release

Hydroxypropyl methylcellulose film system

Hydroxypropyl methylcellulose mixture

Hydroxypropyl methylcellulose phthalate

Hydroxypropyl methylcellulose phthalate HPMCP)

Hydroxypropyl methylcellulose processability

Hydroxypropyl methylcellulose properties

Hydroxypropyl radicals, reaction

Hydroxypropyl substituent

Hydroxypropyl- -cyclodextrins

Hydroxypropyl-/3-cyclodextrin

Hydroxypropyl-CDs

Hydroxypropyl-P-CD

Hydroxypropyl-P-cyclodextrin

Hydroxypropyl-f!-cyclodextrin

Hydroxypropyl-jS-cyclodextrin

Hydroxypropyl-side-chains

Hydroxypropyl/i-cyclodextrin

Hydroxypropylated lignins

Hydroxypropylated starch

Hydroxypropylated starch cross-linked

Hydroxypropylated starch retrogradation

Hydroxypropylation, guar polymer

Methyl hydroxypropyl cellulose MHPC)

Oxidized Hydroxypropyl Starch

P-Hydroxypropyl acrylate

P-Hydroxypropyl benzoate

Poly[ -block- (2-hydroxypropyl

Polymers hydroxypropyl cellulose

Polymers hydroxypropyl methylcellulose

Potato starch hydroxypropylation

Propylene oxide Hydroxypropyl cellulose

Stabilizing agents hydroxypropyl cellulose

Starch hydroxypropyl ethers

Suspending agents hydroxypropyl cellulose

Water-soluble hydroxypropyl

Water-soluble polymer hydroxypropyl methylcellulose

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