Methyl cellulose solution preparation

Instruction B. A solution of an ethylene-vinyl acetate copolymer is prepared in a stirrer autoclave in vinyl chloride (vinylidene chloride) while adding azodiisobutyronitrile dissolution takes place at 25° to 30°C. for four hours. A 1% methyl cellulose solution is introduced into the autoclave under pressure, the content is stirred vigorously (400 r.p.m.) at 25 °C. for two hours, and polymerization is effected by temperature increase at the same speed of agitation. After the polymerization is complete, the bead polymer is isolated, washed with large amounts of water, and dried in vacuo at 50°C. 

Proteins or antibodies (36 pg) were mixed with ampholine pH 3.5—9.5 (final concentration of 5%, Amersham Biosciences, distributed by GE Healthcare, Uppsala, Sweden), p7 markers (Bio-Rad, Hercules, CA), and hydroxypropyl methyl cellulose (final concentration of 0.2% HPMC, Sigma-Aldrich, St. Louis, MO). The final protein concentration was 0.3mg/mL. Figure 17 shows a schematic of the sample preparation. The mixture was mixed thoroughly and was introduced to the capillary (eCAP neutral-coated, 50 micron X 30 cm, Beckman, Fullerton, CA) by hydrodynamic injection. Injections were performed using 20 psi for 99 s. The solution was then separated under an electric field of 25 kV for 10 min. The focused protein was then pushed/pulled out of the capillary through a mobilization process using the cathodic mobilizer (Bio-Rad, Hercules, CA). 

Martin and Porter (19) described a partition chromatographic procedure and first demonstrated the presence of at least one minor active component in the crystalline enzyme preparation. King and Craig (20) found a solvent system permitting effective countercurrent distribution of ribonuclease, ethanol water ammonium sulfate in the ratios 25.9 -57.6 16.5. The principal component of the Kunitz preparation behaved as an almost ideal solute with a partition ratio of 0.8. Albertsson has provided a liquid polymer countercurrent system based on dextrari and methyl cellulose (21). 

Methylcellulose Methylated cellulose with a methoxy content of about 6-15% Solutions are stable at pH 2-12 but coagulate or precipitate in presence of SO% C02 or PO% Ophthalmic and burn preparations, nose drops and ointments... 

All esterification processes with acetic anhydride yield the fully esterified ester as the first soluble product. If the reaction medium is a solvent for the triester a solution is obtained, and if a reaction which retains the fiber structure is employed, samples taken at intervals are all insoluble in solvents until complete esterification is attained. The process in this way differs from nitration, in which soluble, partially esterified products are obtained by adjustment of the concentration of the nitration acids. In the etherification of cellulose, the ethers (e.g., methylated cellulose) prepared by partial substitution are also soluble products, exhibiting continuous, gradual changes in solubility characteristics with increasing substitution. 

In the present work, freeze-drying was used to prepare reticulated porous YSZ ceramics and the methyl cellulose (MC) solution was added in the aqueous ceramic slurry to modify the morphologies of pores. The influences of solid loading and MC concentration on microstmcture, porosity and bulk density were investigated. 

Solutions Preparation. An amine oxide-based cellulose solvent which was still liquid at room temperature was selected. As described earlier (9), it consisted in a mixture of 22 % N-Methyl morpholine N-oxide (HMNO), 65 % N-N-dimethyl ethanolcimine K-oxide (DMEAO) and 13 4 H O (W/W). 5 nqs of CB llulose to which were added 5 mgs of n-propyi gallate, a cellulose stabilizer (10) were dissolved in lOcc of cellulose solvent at 120 C with stirring. Dissolution took place in 15 minutes, following which the solutions were allowed to cool. They were then stored in a dessicator. 

We have previously reported studies on the distribution of substituents in partially etherified celluloses which were prepared from heterogeneous alkali cellulose and from homogeneous nonaqueous cellulose solutions (21). In the latter case, partially substituted cellulose ethers such as methyl- and carboxymethyl-celluloses were prepared from SO2-DEA-DMSO solutions of cellulose by additions of powdered NaOH as a base. 

Stationary phase In order to prepare chiral stationary phase, 10 g of -cyclodextrin (/3-CD) and 5 g of silica gel H were weighed and dried at 110 C in an oven under vacuum for 12 h. /3-CD was dissolved in approximately 120 ml of anhydrous dimethylformamide (DMF) with a small amount of sodium the mixture was stirred for 2-3 h at 90" C and filtered. Silica gel H and 2.5 g of KH-560 (3-glycidoxypropyltrimethoxysilane) were added to the filtrate and the mixture was stirred for 12-18 h at 90" C. The suspension was filtered and washed with DMF, toluene, methanol, water, again with methanol, and then dried in air. To 2 g of obtained /3-CD-bonded silica gel, 6 ml of 0.3% aqueous solution of carboxy-methyl cellulose (CMC) sodium were added, and the slurry obtained was spread as a layer 0.2-0.4 mm thickness on glass plates 2.5 x 7.5 cm in size. Plates were dried in air and activated before use in an oven at 80°C for 1 h. 

The low-substituted hydroxyethylcellulose which, like methyl- and ethylcellulose, is soluble in alkali, particularly when cooled, has much to recommend it from an industrial point of view. It can be formed by the action of only small quantities (0.25 to 0.5 moles) of ethylene oxide on alkali cellulose.47 The reaction product need not be isolated since there are no salts formed, but may be diluted with water or weak alkali to give a spinning solution. The product should therefore be quite cheap. Preparation and properties of hydroxyethylcellulose have been discussed by Schorger and Shoemaker.47... 

For the preparation of the triazine membranes, the entire solid support (cellulose or polypropylene membrane) was treated with a 5 m solution of the corresponding amine in l-methyl-2-pyrrolidinone (NMP) and a 1 m solution of cesium phenolate in dimethyl sulfoxide (2 p L of each at one spot) and subsequently heated in a domestic microwave oven for 3 min. After washing the support successively with... 

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