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    METHOD FOR COLD-MILLING CELLULOSE DERIVATIVES
    11.
    发明专利
    METHOD FOR COLD-MILLING CELLULOSE DERIVATIVES 未知

    公开(公告)号：CA1067055A

    公开(公告)日：1979-11-27

    申请号：CA221298

    申请日：1975-03-05

    Applicant: HOECHST AG

    Inventor： KOSTRZEWA MICHAEL ,  HOLST ARNO ,  BUCHBERGER GERHARD

    IPC: B02C19/18 ,  B29B13/10 ,  C08J3/12 ,  C08B11/20

    Abstract: This invention relates to an improvement in the method for the cold-milling of a cellulose derivative, in which the cellulose derivative is cooled by means of liquid nitrogen until it becomes brittle and the thus cooled cellulose derivative is milled in a mill, the improvement comprising cold-milling a cellulose derivative which is soluble or swellable in water and has a water content of between 40 and 150 per cent by weight, based on its dry weight, and which is, at 20.degree.C, able to absorb, during swelling, more than 150 per cent by weight of water, based on its dry weight.

    PROCESS FOR THE PRODUCTION OF WATER-ADSORBING BUT WATER-INSOLUBLE CELLULOSE ETHERS
    13.
    发明专利
    PROCESS FOR THE PRODUCTION OF WATER-ADSORBING BUT WATER-INSOLUBLE CELLULOSE ETHERS 未知

    公开(公告)号：CA1029371A

    公开(公告)日：1978-04-11

    申请号：CA214250

    申请日：1974-11-20

    Applicant: HOECHST AG

    Inventor： HOLST ARNO ,  LASK HELMUT

    IPC: C08B11/187 ,  A61L15/28 ,  C08B11/14 ,  C08B11/193 ,  C08B15/10

    Abstract: This invention relates to an improvement in the process for the production of water-adsorbing, but largely water-insoluble, cellulose ethers, in which cellulose is alkalized in the presence of alkali and isopropanol as a reaction medium and is so reacted with an etherification agent that by etherification only a water-soluble cellulose ether is produced, and in which process a modification agent which is able to react with the still free hydroxyl groups of the cellulose anhydro glucose groups in an alkaline reaction medium is reacted before, during, or after the etherification, the improvement comprising effecting the etherification of cellulose to carboxymethyl cellulose, carboxymethyl hydroxyethyl cellulose, hydroxyethyl cellulose, or methylhydroxyethyl cellulose, reacting with the modification agent in the presence of 0.8 to 7.5 parts by weight of isopropanol, based upon the cellulose weight, and employing a modification agent being one of the formulae HOHH H ¦ PARALLEL ¦¦ ¦ (I) H2C=C-C-N-C-R1 and (II) H2C=C-SO2-NH2, ¦ R2 R1 in formula I being hydroxyl, or an acylamino or etherified carbamino group, and R2 in formula I being hydrogen or a carboxyl group.

    14.
    发明专利
    未知

    公开(公告)号：FI761259A

    公开(公告)日：1976-11-08

    申请号：FI761259

    申请日：1976-05-05

    Applicant: HOECHST AG

    Inventor： HOLST ARNO ,  LASK HELMUT ,  KOSTRZEWA MICHAEL

    IPC: A61F13/472 ,  A61F13/15 ,  A61F13/53 ,  A61L15/28 ,  A61L15/60 ,  B01J20/24 ,  B01J20/281 ,  C08B11/187 ,  C08B11/193 ,  C08B15/00 ,  C08B15/10 ,  G01N30/88 ,  C08B

    Abstract: This invention relates to an improvement in the process for the production of water-adsorbing, but at least partially water-insoluble cellulose ethers in which cellulose is alkalized in a liquid reaction medium and etherified in a manner such that by etherification only an at least largely water-soluble carboxymethyl cellulose, carboxymethyl hydroxyethyl cellulose, hydroxyethyl cellulose or methyl hydroxyethyl cellulose is produced, and in which the cellulose is reacted in an alkaline reaction medium before, during, or after the etherification with a modification agent reactive with the still free hydroxyl groups of the cellulose anhydro glucose groups, said modification agent having one of the formulae I II in which R1 is hydroxyl, an acylamino or esterified carbamino group, and R2 is hydrogen or a carboxyl group, THE IMPROVEMENT COMPRISING EFFECTING ALKALIZATION, ETHERIFICATION, AND MODIFICATION IN A LIQUID REACTION MEDIUM OTHER THAN ISOPROPYL ALCOHOL.

    17.
    发明专利
    未知

    公开(公告)号：NO891015L

    公开(公告)日：1989-09-11

    申请号：NO891015

    申请日：1989-03-09

    Applicant: HOECHST AG

    Inventor： MILLER DENNIS ,  SCHMIDT MANFRED ,  HOLST ARNO ,  HALASZ SIGMAR-PETER VON

    IPC: C09K8/584 ,  C09K23/02 ,  C09K23/42 ,  E21B43/22 ,  B01F17/12 ,  B01F17/42

    Abstract: Surfactant mixtures made from 5 to 80% by weight of an ether sulfonate, 5 to 80% by weight of an alkyl or alkylphenol polyglycol ether and 10 to 80% by weight of an alkanesulfonate, petroleumsulfonate or alkylbenzenesulfonate. This combination of surfactants produces stable, aqueous solutions or dispersions which are highly suitable for surfactant flooding in tertiary oil recovery since these aqueous surfactant solutions or dispersions form microemulsions with the oil even at high salinities.

    PROCESS FOR REDUCING THE VISCOSITY OF CELLULOSE ETHERS BY MEANS OF OZONE AND APPLICATION THEREOF
    20.
    发明专利
    PROCESS FOR REDUCING THE VISCOSITY OF CELLULOSE ETHERS BY MEANS OF OZONE AND APPLICATION THEREOF 未知

    公开(公告)号：CA1127635A

    公开(公告)日：1982-07-13

    申请号：CA349807

    申请日：1980-04-14

    Applicant: HOECHST AG

    Inventor： HOLST ARNO ,  PERPLIES EBERHARD

    IPC: C08B11/02 ,  C08B11/20

    Abstract: Hoe 79/K 015 PROCESS FOR REDUCING THE VISCOSITY OF CELLULOSE ETHERS BY MEANS OF OZONE AND APPLICATION THEREOF This invention relates to a process for reducing the viscosity of cellulose ethers by reacting a water-soluble cellulose ether with ozone in the presence of water, wherein said cellulose ether which is moist with water and has a dry content of from 20 to 95% by weight is reacted with an ozone/oxygen mixture or with an ozone/air mixture at a temperature of about 0 to 60.degree. C.

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