摘要:
Antifoams and/or deaerators based on oil-in-water dispersions, whose oil phase contains at least one compound from the group consisting of the alcohols of at least 12 carbon atoms, alkoxylated fatty alcohols, mono-, di- and triglycerides of fatty acids, fatty acid esters of carboxylic acids of at least 12 carbon atoms and monohydric to tetrahydric alcohols of 1 to 24 carbon atoms, hydrocarbons having a boiling point above 200° C., fatty acids of 12 to 26 carbon atoms, 3-thiaalkan-1-ols, 3-thiaoxoalkan-1-ols, 3-thiadioxoalkanols and esters of thiaalkane compounds in combination with (i) at least one polyglyceryl ester which is obtainable by at least 20% esterification of polyglycerol with a carboxylic acid of 12 to 36 carbon atoms and (ii) at least one bisamide of ethylenediamine and carboxylic acids of 10 to 36 carbon atoms and whose aqueous phase contains at least one stabilizer, water and, if required, a thickener, for aqueous media which tend to form foam, are used for foam control of aqueous media which tend to form foam, in particular for foam control in pulp cooking, pulp washing, the beating of paper stock, papermaking and the dispersing of pigments for papermaking.
摘要:
The present invention relates to novel oil-in-water dispersions which comprise a) at least one water-insoluble oxygen-containing organic substance which is solid at room temperature and b) at least one amide compound of the formula I, in which the variables R, R1, R2, A, B, X and Z have the meanings given in the description and the claims, and to the use thereof as antifoams and/or deaerators in aqueous systems which have a tendency toward foam formation.
摘要:
A defoaming agent and/or deaerator for aqueous foamable media based on oil-in-water dispersions. The oil phase contains at least one compound from fatty alcohols, fatty acid monoglycerides, diglycerides, and triglycerides, fatty acid ester of fatty acids and monovalent to trivalent alcohols, 3-thiaalkane-1-ole, 3-thiaoxide alkane-1-ole, 3-thiadioxide-alkane-ole, and thiaalkane esters in combination with (i) at least one polyglycerine that is obtained by esterification of at least 20 percent of polyglycerine with 12 to 36 C carboxylic acid, and (ii) at least one bisamide consisting of ethylene diamine and 10 to 36 C atom carboxylic acids, while the aqueous phase thereof contains at least one stabilizer, water, and an optional thickener, for aqueous media that tend to foam. Also disclosed are methods of controlling foam by adding the dispersions to a process, particularly during cellulose boiling, cellulose washing, grinding of paper pulp, paper production, and dispersion of pigments used for paper production.
摘要:
Emulsifier-free antifoams are obtainable by mixing a) from 80 to 99% by weight of at least one finely divided, virtually water-insoluble, inert solid with b) from 1 to 20% by weight of at least one hydrophobic, organic compound which has an antifoam action and is solid at room temperature in the absence of a solvent in a shear gradient such that the particle size of the compounds (b) which have an antifoam action is reduced to a mean particle size of from 0.5 to 15 μm, emulsifier-free oil-in-water dispersions of mixtures of (a) and (b) are prepared by mixing the component (a) in an amount of from 80 to 99% by weight with the compounds of component (b) in an amount of from 1 to 20% by weight in the absence of emulsifiers in an extruder or kneader in a manner such that the mean particle size of the component (b) in the mixture is brought to 0.5 to 15 μm, at up to 100° C., and emulsifying the mixture in water, and the oil-in-water dispersions thus obtainable are used as antifoams and/or deaerators for aqueous, disperse or nondisperse liquids, in particular as antifoams and/or deaerators in the paper industry, in the food industry and in wastewater treatment plants.
摘要:
Aqueous dispersions of reactive sizes comprise cationic polymers comprising vinylamine units as a protective colloid, the protective colloid comprising less than 0.0001% by weight, based on the protective colloid, of diketenes.
摘要:
Aqueous dispersions of reactive sizes comprise cationic polymers comprising vinylamine units as a protective colloid, the protective colloid comprising less than 0.0001% by weight, based on the protective colloid, of diketenes.
摘要:
The invention relates to a process for producing polyester polyols with secondary hydroxyl end groups, including the step of the reaction of a polyester including carboxyl end groups with an epoxide of the general formula (1): wherein R1 stands for an alkyl residue or an aryl residue and the reaction is carried out in the presence of a catalyst that includes at least one nitrogen atom per molecule. The process is distinguished in that the polyester including carboxyl end groups exhibits an acid value from ≧25 mg KOH/g to ≦400 mg KOH/g and a hydroxyl value from ≦5 mg KOH/g and in that the polyester including carboxyl end groups is produced by ≧1.03 mol to ≦1.90 mol carboxyl groups or carboxyl-group equivalents of an acid component being employed per mol hydroxyl groups of an alcohol. The polyester polyols obtained, including secondary hydroxyl end groups, can be used for the purpose of producing polyurethane polymers.
摘要:
The invention concerns a process for the preparation of a hardening accelerator composition by reaction of a water-soluble calcium compound with a water-soluble silicate compound and by reaction of a calcium compound with a silicon dioxide containing component under alkaline conditions, in both cases the reaction being carried out in the presence of a polycondensate containing at least one structural unit consisting of an aromatic or heteroaromatic moiety bearing a polyether side chain and at least one structural unit consisting of an aromatic or heteroaromatic moiety bearing at least one phosphoric acid ester group and/or its salt. The invention concerns a composition of calcium silicate hydrate and the polycondensate, its use as hardening accelerator and for the reduction of the permeability of hardened compositions.
摘要:
The invention relates to a process for the preparation of polyether polyols with equivalent molecular weights of from 8,000 to 20,000 g/mol from one or more H-functional starter compounds and one or more alkylene oxides in the presence of a double metal cyanide catalyst, characterized in that the alkylene oxides are metered into the reactor in the course of from 15 to 23 h.
摘要:
The present invention relates to is coupling process for the preparation of polyether polyols starting from highly functional starter compounds that are solid or highly viscous under reaction conditions and monofunctional starter compounds that are liquid under reaction conditions with Zerewitinoff-active hydrogen atoms.