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Acetic acid Hydroxypropyl cellulose

The GBR resin works well for nonionic and certain ionic polymers such as various native and derivatized starches, including sodium carboxymethylcel-lulose, methylcellulose, dextrans, carrageenans, hydroxypropyl methylcellu-lose, cellulose sulfate, and pullulans. GBR columns can be used in virtually any solvent or mixture of solvents from hexane to 1 M NaOH as long as they are miscible. Using sulfonated PDVB gels, mixtures of methanol and 0.1 M Na acetate will run many polar ionic-type polymers such as poly-2-acrylamido-2-methyl-l-propanesulfonic acid, polystyrene sulfonic acids, and poly aniline/ polystyrene sulfonic acid. Sulfonated columns can also be used with water glacial acetic acid mixtures, typically 90/10 (v/v). Polyacrylic acids run well on sulfonated gels in 0.2 M NaAc, pH 7.75. [Pg.400]

Cellulose based mesophases have displayed a somewhat steeper inverse dependence of pitch to concentration than that reported by Toriumi (29). A value of x = 3 has been reported for hydroxypropyl cellulose in water (31), for acetoxypropyl cellulose in acetone (32) and for hydroxypropyl cellulose in acetic acid and in methanol (28). Our data for cellulose in NH3/NH4SCN show a reasonably straight line when p l/3 was plotted vs. cellulose concentration (Figure 11), which is in accord with earlier reports (28,29,31,32). [Pg.170]

Threshold volume fractions observed for cellulose acetate (CA and CTA), ethyl cellulose (EC) and hydroxypropyl cellulose (HPC), each in various solvents, are presented in Table 3. The results depend to some extent on the solventThe data included are not exhaustive. Other cellulose esters exhibit mesomorphic behavior Chanzy et al. observed mesomorphic behavior in solutions of cellulose itself when dissolved in N-methylmorpholine N-oxide containing water at concentrations of cellulose in the range 20-55 % w/v, depending on the temperature, the water content of the solvent and the degree of polymerization of the cellulose. Solutions of cellulose in mixtures of trifluoroacetic acid with 1,2-dichloroethane or with chloroform are hkewise lyotropic at concentrations of 20% (w/v) and above according to Patel and Gilbert... [Pg.20]

Poly(methyl acrylate-co-methyl methacrylate-co-methacrylic acid) 7 3 1 Poly(methacrylic acid-co-methyl methacrylate) 1 2 Hydroxypropyl cellulose Ethyl cellulose Cellulose acetate butyrate Cellulose acetate phthalate Poly(ethylene oxide)... [Pg.219]

Ingredients Calcium Carbonate, Microcrystalline Cellulose, Magnesium Oxide, Ferrous Fumarate, Ascorbic Acid, Maltodextrin, Gelatin, dl-Alpha-Tocopheryl Acetate, Dicalcium Phosphate Less than 2% of Beta-Carotene, Biotin, Cholecalciferol, Croscarmellose Sodium, Cupric Oxide, Cyanocobalamin, D-Calcium Pantothenate, FD C Red 40 Dye, FD C Red 40 Lake, FD C Yellow 6 Lake, Folic Acid, Hydroxypropyl Methylcellulose, Niacinamide, Polyethylene Glycol, Polysorbate 80, Potassium Iodide, Pyridoxine Flydrochloride, Riboflavin, Silicon Dioxide, Soybean Oil, Starch, Stearic Acid, Thiamine Mononitrate, Titanium Dioxide (color), Vitamin A Acetate, Zinc Oxide... [Pg.144]

Many cellulose derivatives form lyotropic liquid crystals in suitable solvents and several thermotropic cellulose derivatives have been reported (1-3) Cellulosic liquid crystalline systems reported prior to early 1982 have been tabulated (1). Since then, some new substituted cellulosic derivatives which form thermotropic cholesteric phases have been prepared (4), and much effort has been devoted to investigating the previously-reported systems. Anisotropic solutions of cellulose acetate and triacetate in tri-fluoroacetic acid have attracted the attention of several groups. Chiroptical properties (5,6), refractive index (7), phase boundaries (8), nuclear magnetic resonance spectra (9,10) and differential scanning calorimetry (11,12) have been reported for this system. However, trifluoroacetic acid causes degradation of cellulosic polymers this calls into question some of the physical measurements on these mesophases, because time is required for the mesophase solutions to achieve their equilibrium order. Mixtures of trifluoroacetic acid with chlorinated solvents have been employed to minimize this problem (13), and anisotropic solutions of cellulose acetate and triacetate in other solvents have been examined (14,15). The mesophase formed by (hydroxypropyl)cellulose (HPC) in water (16) is stable and easy to handle, and has thus attracted further attention (10,11,17-19), as has the thermotropic mesophase of HPC (20). Detailed studies of mesophase formation and chain rigidity for HPC in dimethyl acetamide (21) and for the benzoic acid ester of HPC in acetone and benzene (22) have been published. Anisotropic solutions of methylol cellulose in dimethyl sulfoxide (23) and of cellulose in dimethyl acetamide/ LiCl (24) were reported. Cellulose tricarbanilate in methyl ethyl ketone forms a liquid crystalline solution (25) with optical properties which are quite distinct from those of previously reported cholesteric cellulosic mesophases (26). [Pg.370]

Fig. 1. Polygonal field texture of a cholesteric solution of hydroxypropyl cellulose (HPC) in acetic acid. Fig. 1. Polygonal field texture of a cholesteric solution of hydroxypropyl cellulose (HPC) in acetic acid.
API active pharmaceutical ingredient, EVA ethyl vinyl acetate, HPMC hydroxypropyl methylceUulose, HPMCAS hydroxypropylmethylceUulose acetate succinate, PLGA poly(lactic-co-glycolic acid), PVP-VA polyvinyl pyrroUdone-co-vinyl acetate, PEG polyethylene glycol, PVP polyvinyl pyrrolidone, EC ethyl cellulose, ERS Eudragit RS, UD under development, M marketed product, W withdrawn from the market Loxley 2010 DiNunzio 2011... [Pg.198]

Hydroxypropyl cellulose / right water, methanol, ethanol, dichloroacetic acid, acetic acid, dimethylacetamide, pyridine, 2-methoxyethanol, 1,4-dioxane, m-cresol... [Pg.366]

As previously discussed, food effects are an important parameter for enteric-coated systems, especially for drugs, that are sensitive to food. Pancreatic enzyme-containing products fail when they come in contact too early with lipids, proteins, and carbohydrates present in food. The clinical efficacy of pancreatic enzymes formulated as enteric-coated tablets was investigated in man and dog [44], The enteric materials examined were hydroxypropyl methylcellulose phthal-ate (HPMCP), cellulose acetate phthalate (CAP), and the methacrylic acid copolymer USP/NF Type C. In vivo behavior monitored by x-ray scintigraphy showed clear differences between the three coating formulations. HPMCP-coated products adhered to the gastric mucosa, whereas CAP and methacrylate copolymer... [Pg.29]

The enteric materials examined were hydroxypropyl methylcellulose phthal-ate (HPMCP), cellulose acetate phthalate (CAP), and the methacrylic acid copolymer USP/NF Type C. In vivo behavior monitored by x-ray scintigraphy showed clear differences between the three coating formulations. HPMCP-coated products adhered to the gastric mucosa, whereas CAP and methacrylate copolymer... [Pg.19]

TRIS(2-HYDROXYPROPYL) AMINE (122-20-3) Combustible solid (flash point 320°F/160°C oc). An organic base. Violent reaction with strong oxidizers, strong acids. Incompatible with organic anhydrides, acrylates, alcohols, aldehydes, alkylene oxides, substituted allyls, cellulose nitrate, cresols, caprolactam solution, epichlorohydrin, ethylene dichloride, isocyanates, ketones, glycols, nitrates, phenols, vinyl acetate. Exothermic decomposition with maleic anhydride. Increases the explosive sensitivity of nitromethane. [Pg.1209]

Cellulose acetate phthalate film-former, enteric pharmaceuticals Hydroxypropyl methylcellulose phthalate film-former, explosives Dibutyl phthalate film-former, fixing lotions PVP/VA/vinyl propionate copolymer VA/crotonates/vinyl propionate copolymer film-former, flexible hoses Ethylene/methyl acrylate copolymer film-former, floor finishes Ethylene/acrylic acid/vinyl acetate copolymer film-former, flooring compounds Acrylamides copolymer film-former, food... [Pg.5251]

Butanediol t-Butyl methacrylate Cellulose acetate propionate Chromic acid Cocamine Copper nitrate (ic) Cl 1-15 pareth-7 Cl 1-15 pareth-9 Cl 1-15 pareth-12 Cyclodextrin 3-Cyclodextrin 1,3-Dichloro-2-propanol Dicocamine Diethylene glycol dimethyl ether DImethylaminopropylmethacrylamide Dimethyl terephthalate ElemI gum Feldspar Furfuryl alcohol Gilsonite Glycerin Hexamethylenediamine Hydroxymethyl dioxoazabicyclooctane N-(2-Hydroxypropyl) benzenesulfonamide Hydroxypropyl-a-cyclodextrin Hydroxypropyi-P-cyclodextrin Hydroxypropyl-y-cyclodextrin Hydroxystearic acid Isobornyl methacrylate Lead... [Pg.5502]

Cltroflex citric acid esters provide a wide range of benefits when used as plasticizers with aqueous- and solvent-based polymers, including acrylic, methacrylic, ethyl cellulose, hydroxypropyl methyl cellulose, nitrocellulose, vinyl acetate, vinyl chloride, vinyl pyrrolidone, vinylidene chloride, axiA urethane polymer systems. [Pg.159]


See other pages where Acetic acid Hydroxypropyl cellulose is mentioned: [Pg.298]    [Pg.105]    [Pg.43]    [Pg.1868]    [Pg.99]    [Pg.1651]    [Pg.1732]    [Pg.337]    [Pg.34]    [Pg.105]    [Pg.298]    [Pg.60]    [Pg.503]    [Pg.263]    [Pg.355]    [Pg.199]    [Pg.215]    [Pg.1085]    [Pg.403]    [Pg.2161]    [Pg.424]    [Pg.333]    [Pg.5230]    [Pg.5251]    [Pg.197]    [Pg.708]    [Pg.637]    [Pg.118]   


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Acetic acid cellulose acetate

Cellulose acetate

Cellulose-acetic acid

Cellulosics cellulose acetate

Hydroxypropylation

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