摘要:
The present invention relates to a process for preparing polyoxyalkylene glycol of high purity and having a low color number from the corresponding alkylene glycol and a starter in the presence of a basic catalyst, wherein a reducing agent is present in the polymerization.
摘要:
A process is described for purifying polyalkylene glycols obtained by adding alkylene oxide to alkylene glycol, in which, after addition is complete, the resultant polyalkylene glycol is treated at a pH of >7 with a bleaching agent selected from the group consisting of peroxides, peracids, percarbonates, perborates, peroxodisulfates or oxygen, in each case with or without addition of a bleaching activator. The process is suitable in particular for preparing polyethylene glycol having molar weights from 196 to 203 g/mol which meets requirements of pharmacopeias.
摘要:
Low viscosity mixtures of(I) from 40 to 97.5% by weight of amphiphilic nonionic graft copolymers comprising, in copolymerized form,(a) at least 20% by weight of polyalkylene oxide units or polyvinylpyrrolidone units as hydrophilic part of the molecule and(b) at least 40% by weight of vinyl ester and/or (meth)acrylic ester units as hydrophobic part of the molecule, and(II) from 2.5 to 60% by weight of at least one viscosity-reducing additive selected from the group consisting of polyalkylene glycols, alkoxylated alcohols, alkoxylated alkylphenols, alkoxylated amines and hydroxy compounds having from 1 to 4 OH groups and from 2 to 10 carbon atoms, the molecular mass M.sub.N of the polymers in each case being not more than 2500, and(III) from 0 to 40% by weight of homogenizing or phase-stabilizing additives, for example water, monobasic and dibasic carboxylic acids having from 8 to 25 carbon atoms, fatty alcohol sulfates and fatty alcohol sulfonates or mixtures thereof,are useful as detergent and cleaner additives.
摘要:
Polyacetals useful as detergent additives contain units of the formula ##STR1## where R is hydrogen, C.sub.1 -C.sub.4 -alkyl or COOM,M is C.sub.1 -C.sub.4 -alkyl or an alkali metal, ammonium or alkanolamine group, andm is from 0 to 9,have K values (determined by the method of H. Fikentscher on the sodium salt in 1% strength by weight aqueous solution at 25.degree. C. and pH 7) of at least 8.5, and are prepared by polymerizing compounds of the formula ##STR2## where R is hydrogen, C.sub.1 -C.sub.4 -alkyl or COOM,M is C.sub.1 -C.sub.4 -alkyl or an alkali metal, ammonium or alkanolamine group,R.sup.2 is C.sub.1 -C.sub.4 -alkyl, andm is from 0 to 9,in the presence of initiators and optionally comonomers with or without hydrolysis of the ester groups.
摘要:
Pulverulent and liquid detergents contain (1) one or more anionic surfactants, one or more nonionic surfactants or mixtures thereof and (2) copolymers in amounts of from 0.1 to 15% by weight preparable by copolymerization of(a) from 10 to 55 mol % of a 1,2-di-C.sub.1 -C.sub.4 -alkoxyethylene,(b) from 10 to 60 mol % of a monoethylenically unsaturated dicarboxylic anhydride of from 4 to 8 carbon atoms,(c) from 0 to 60 mol % of a monoethylenically unsaturated C.sub.3 -C.sub.8 -monocarboxylic acid and(d) from 0 to 20 mol % of another monoethylenically unsaturated monomerand subsequent hydrolysis of the anhydride groups of the copolymerized monomer (b) or reaction of these groups with an alcohol or an amine.Preferred copolymers contain 1,2 dimethoxyethylene as the (a) monomer, maleic acid as the (b) monomer, and acrylic acid as the (c) monomer.
摘要:
A composition for cyanide leaching which comprises at least one nonionic surfactant and a process for extracting metals using the abovementioned composition are described.
摘要:
An aqueous sulfuric acid-containing composition which comprises at least one surfactant, and a process for extricating metal from metal-containing materials with the aid of this aqueous sulfuric acid-containing composition are described.
摘要:
A process is described for purifying polyalkylene glycols obtained by adding alkylene oxide to alkylene glycol, in which, after addition is complete, the resultant polyalkylene glycol is treated at a pH of >7 with a bleaching agent selected from the group consisting of peroxides, peracids, percarbonates, perborates, peroxodisulfates or oxygen, in each case with or without addition of a bleaching activator.The process is suitable in particular for preparing polyethylene glycol having molar weights from 196 to 203 g/mol which meets requirements of pharmacopeias.
摘要:
The invention relates to alkylglycol alkoxylates and alkyldiglycol alkoxylates that are obtainable by alkoxylating C4-8 alkylglycols or diglycols with C2-5 alkoxides up to an average alkoxylation degree of 1 to 8, based on the C4-8alkylglycols or diglycols. The invention further relates to mixtures from C2-5 alkoxylates of C4-8 alkylgycols or -diglycols that have an average alkoxylation degree of 1 to 8 and tensides that have an interfacial tension of less than 45 mN/m at 20° C. when dissolved in an amount of 5 g/l of water, and/or to diyhdroxyalkins or derivatives thereof.