Polyvinyl alcohol

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:-2.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 2,683 ml of distilled water, 1,114 ml of a 20% by weight HCl and 1,190 ml of a 19.7% by weight aqueous solution of a fully hydrolyzed polyvinyl alcohol, viscosity 3.68 mPas (DIN 53015; Höppler method; 4% by weight aqueous solution), were charged to a 6 liter glass reactor and cooled to −2° C. within a period of one hour, with stirring. A mixture made from 2.5 g of 3,3-diethoxypropyltriethoxysilane and 188 ml (151.6 g) of butyraldehyde, cooled in advance to −4° C., was then added over a period of 5 minutes, with an attendant rise in internal reactor temperature to −0.7° C. The mixture was then rapidly cooled again to −2° C. 3 minutes after addition of the mixture the reaction mixture, which had until then been clear, was observed to become cloudy, and the product precipitated as little as 5 minutes later. After 40 minutes reaction time at −2° C. the temperature was increased to 25° C. over a period of 3.5 hours, and this temperature was maintained for a further 2 hours. The product was then separated by suction filtration and washed with distilled water until the filtrate gave a neutral reaction. The moist product was dried to a solids content of at least 98%, initially at 22° C. and then at 35° C. in vacuo, yielding a modified polyvinyl butyral having 17.8% by weight of vinyl alcohol units, 1.5% by weight of vinyl acetate units, and 80.7% by weight of vinyl butyral units. The viscosity (DIN 53015; Höppler method; 10% by weight ethanolic solution) was 25.1 mPas. The Si content was determined to be 0.05% by weight. cooled in advance to −4° C. was then added over a period of 5 minutes, with an attendant rise in internal reactor temperature to −0.7° C The mixture was then rapidly cooled again to −2° C 3 minutes after addition of the mixture the reaction mixture, which the product precipitated as little as 5 minutes later After 40 minutes reaction time at −2° C. the temperature was increased to 25° C. over a period of 3.5 hours this temperature was maintained for a further 2 hours The product was then separated by suction filtration washed with distilled water until the filtrate gave a neutral reaction The moist product was dried to a solids content of at least 98%, initially at 22° C.

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To 50 ml. of a medium comprising Brewer modified throgylcollate broth (Baltimore Biological Laboratories), a stock culture of Clostridium perfringens ATCC 19574 is inoculated under anaerobic conditions. The medium is incubated under anaerobic conditions, at 37° C for a period of 96 hours and the resultant culture is employed to inoculate 1 liter of the same medium. At the time of inoculation, 2 gm. of 3α, 7α, 12α-trihydroxy-5β-cholanic acid dissolved in 15 ml. of ethenol and sterilized through a Seitz pad is added. The flask is incubated anaerobically for 72 hours and the broth is then filtered on a Buchner funnel with the aid of filter cel and the filtrate is then acidified to pH 1-2 with HCl, extracted 3 times with ether and the combined ether extracts washed with water, dried over sodium sulfate, and evaporated to dryness in vacuo. The residue is then crystalized from ethyl acetate-heptane to yield crude 3α, 7α,-dihydroxy-5β-cholanic acid. If further purification is required, the resultant product may be further treated in accordance with the procedures set forth in my copending application, Ser. No. 417,170, filed Nov. 19, 1973. is added The flask is incubated anaerobically for 72 hours the broth is then filtered on a Buchner funnel with the aid of filter cel extracted 3 times with ether the combined ether extracts washed with water dried over sodium sulfate evaporated to dryness in vacuo The residue is then crystalized from ethyl acetate-heptane

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Comparative experiments were carried out in which in place of N-octadecyl gluconamide, the suspension stabilizers Gohsenol KP 08, Armotan® MP (sorbitan monopalmitate), Armotan® ML (sorbitan monolaurate) Tween® 20 (polyoxyethylene (20) monolaurate) and Tween® 21 (polyoxyethylene (4) monolaurate) were used. Only the results obtained with Tween® 21 (polyoxyethylene (4) monolaurate) compared with those obtained with N-octadecyl gluconamide. When only Gohsenol KP 08 was used, the results obtained were distinctly poorer. In all other cases destabilization of the suspension was observed after 1 to 2 hours polymerization.

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Comparative experiments were carried out in which in place of N-octadecyl gluconamide, the suspension stabilizers Gohsenol KP 08, Armotan® MP (sorbitan monopalmitate), Armotan® ML (sorbitan monolaurate) Tween® 20 (polyoxyethylene (20) monolaurate) and Tween® 21 (polyoxyethylene (4) monolaurate) were used. Only the results obtained with Tween® 21 (polyoxyethylene (4) monolaurate) compared with those obtained with N-octadecyl gluconamide. When only Gohsenol KP 08 was used, the results obtained were distinctly poorer. In all other cases destabilization of the suspension was observed after 1 to 2 hours polymerization.

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To 100 g of the same copolymer was added 1500 ml of ethyl acetate, 40 ml of concentrated ammonium hydroxide and 40 ml of water. After two days with stirring, the polymer dissolved to give a gel. During the next three weeks at room temperature, a progressive decrease in viscosity of the solution was noted. At this time the solution was heated to remove ammonia, giving a partially saponified polymer of composition 32.4 wt % vinyl acetate, 16.4 wt % vinyl alcohol, 38 wt % TFE, and 13.2 wt % HFP in a 27.4 wt % solids solution in ethyl acetate. the polymer dissolved to give a gel During the next three weeks at room temperature At this time the solution was heated to remove ammonia

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To 100 g of a copolymer made by the process of the present invention and having the composition 55.8 wt % vinyl acetate, 32.8 wt % TFE and 11.4 wt % HFP, was added 500 ml of methanol and 40 ml of concentrated ammonium hydroxide to form a copolymer suspension in the methanol. After three days at room temperature with occasional shaking, the resulting solution was heated to remove the reaction by-products to give a 25.1 wt % solution of polymer of composition 2.7 wt % vinyl acetate, 37.4 wt % vinyl alcohol, 44.5 wt % TFE, and 15.4 wt % HFP. the resulting solution was heated to remove the reaction by-products

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: This Example shows the preparation of high TFE content copolymer. The conditions of Example III were repeated except that a total of 470 mg of APS was added, the TFE addition rate was 0.01 lb/rain (4.5 g/min), the vinyl acetate addition rate was 2 ml/min., and the final agitation rate was 80 rpm. 2580 g of a 25.0 wt % solids colloidal dispersion was obtained. To 100 g of the isolated, dried polymer was added 500 ml of methanol and 40 ml of concentrated ammonium hydroxide. After several weeks at room temperature with occasional shaking, the resulting solution was heated to remove the reaction by-products and there was obtained a hazy, viscous solution of 19 wt % solids of approximate composition 82 wt % TFE, 16 wt % vinyl alcohol, and 2 wt % vinyl acetate. Upon evaporation of the solvent at 50° C. in a vacuum oven for one day, a clear, somewhat rubbery melt fabricable polymer was obtained. the preparation of high TFE content copolymer was added the TFE addition rate 2580 g of a 25.0 wt % solids colloidal dispersion was obtained After several weeks at room temperature with occasional shaking the resulting solution was heated to remove the reaction by-products

Conditions: temp:90.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 1000 parts by weight of a 10% by weight solution of polyvinyl alcohol having a degree of polymerization Pn of about 1300 and a vinyl acetate unit content of 1.8% by weight are heated to 90° C. and, after the addition of 9.3 parts by weight of 10% by weight sodium hydroxide solution, stirred for 30 minutes at 90° C. The solution is then cooled to 16° C., the cooling time between 40° C. and 16° C. being 20 minutes, and treated with 65 parts by weight of concentrated hydrochloric acid. 57.6 parts by weight of n-butyraldehyde are added continuously to this mixture in the course of 20 minutes, with stirring. One hour after completion of the aldehyde addition, the batch is heated with stirring to 50° C. within one hour and kept for three hours at this temperature. After working up as described in Example 1, a pulverulent polyvinylbutyral containing 21.6% by weight of vinyl alcohol units and 0.1% by weight of vinyl acetate units is obtained. The polymer is mixed with 29% by weight of triethylene glycol bis-heptanoate as the plasticizer and 0.015% by weight of potassium formate (10% by weight in water), relative to the mixture, and extruded to give a 0.76 mm thick film. Laminated glass is produced from the film, as described in Example 1. The solution is then cooled to 16° C. the cooling time between 40° C. and 16° C. being 20 minutes with stirring the batch is heated with stirring to 50° C. within one hour kept for three hours at this temperature