摘要:
Graft polymers are obtainable by free radical polymerization of(A) monomers or monomer mixtures of(a) from 10 to 100% by weight of open-chain N-vinylcarboxamides(b) from 0 to 90% by weight of other, carboxyl-free monoethylenically unsaturated monomers which are copolymerizable with the monomers (a) and(c) from 0 to 5% by weight of monomers containing two or more ethylenically unsaturated, non-conjugated double bonds in the molecule,in the presence of(B) natural substances containing saccharide structures, such as mono-, oligo- and polysaccharides,in a weight ratio (A):(B) of from 95:5 to 20:80 and, if required, subsequent hydrolysis of the amido groups of the polymerized monomers (a) of the graft polymer with formation of amino groups, and said polymers are used as dry and wet strength agents for paper, board and cardboard.
摘要:
Graft polymers are obtainable by free radical polymerization of(A) monomers or monomer mixtures of(a) from 10 to 100% by weight of open-chain N-vinylcarboxamides(b) from 0 to 90% by weight of other, carboxyl-free moneothylenically unsaturated monomers which are copolymerizable with the monomers (a) and(c) from 0 to 5% by weight of monomers containing two or more ethylenically unsaturated, non-conjugated double bonds in the molecule, in the presence of(B) natural substances containing saccharide structures, such as mono-, oligo- and polysaccharides,in a weight ratio (A):(B) of from 95:5 to 20:80 and, if required, subsequent hydrolysis of the amido groups of the polymerized monomers (a) of the graft polymer with formation of amino groups, and said polymers are used as dry and wet strength agents for paper, board and cardboard.
摘要:
Nitrile impurities are eliminated from polymers which contain acyclic N-vinyl-carboxamide and/or vinylamine units by treating the polymers with at least one oxidizing agent a) with exposure to light and/or b) in the presence of heavy metal ions.
摘要:
Graft polymers are obtainable by free radical polymerization of(A) monomers or monomer mixtures of(a) from 10 to 100% by weight of open-chain N-vinylcarboxamides(b) from 0 to 90% by weight of other, carboxyl-free monoethylenically unsaturated monomers which are copolymerizable with the monomers (a) and(c) from 0 to 5% by weight of monomers containing two or more ethylenically unsaturated, non-conjugated double bonds in the molecule, in the presence of(B) natural substances containing saccharide structures, such as mono-, oligo- and polysaccharides,in a weight ratio (A):(B) of from 95:5 to 20:80 and, if required, subsequent hydrolysis of the amido groups of the polymerized monomers (a) of the graft polymer with formation of amino groups, and said polymers are used as dry and wet strength agents for paper, board and cardboard.
摘要:
Copolymers which are obtained by copolymerization ofa) from 5 to 99 mol % of N-vinylcarboxamides,b) from 95 to 1 mol % of monoethylenically unsaturated carboxylic acids and/or the alkali metal, alkaline earth metal, ammonium or amine salts thereof, and if required,c) up to 30 mol % of other monoethylenically unsaturated compounds, and if required,d) up to 2 mol % of crosslinking agents,and subsequent partial or complete elimination of the acyl groups from the N-vinylcarboxamides polymerized in the copolymer, with formation of amino or ammonium groups, are used as additives to paper stock for increasing the drainage rate and the retention in papermaking, and the dry and wet strength of the paper.
摘要:
Abstract of the Disclosure: Insoluble, only slightly swellable polymers containing amino groups, which can be obtained from popcorn polymers containing units of the structure ##STR1## where R and R.sup.1 are H or C.sub.1 -C.sub.4 -alkyl, by eliminating the group R--CO-- from at least 2% of the incorporated units of the structure I, with the formation of units of the structure II ##STR2## a process for the preparation of the amino-containing popcorn polymers by polymerizing N-vinylcarboxamides and, if desired, other monoethylenically unsaturated monomers copolymerizable therewith with from 0.1 to 10% by weight, based on the monomers used in the polymerization, of a compound containing at least two ethylenically unsaturated non-conjugated double bonds as crosslinking agent, with exclusion of oxygen and polymerization initiators, to form popcorn polymers, and elimination of formyl groups from at least 2% of the copolymerized N-vinylcarboxamides, and the use of the resulting insoluble, only slightly swellable polymers containing amino groups as ion exchangers or adsorber resins for metal ions are described.
摘要:
Graft polymers which contain N-vinyl units and in which the grafting base is a polymer which contains in each case at least 5% by weight of units of the formulae ##STR1## where R.sup.1 and R.sup.2 are each H or C.sub.1 -C.sub.6 -alkyl, monoethylenically unsaturated monomers are grafted onto the grafting base in a weight ratio of from 100:1 to 1:100, and which have K values of at least 7 (determined according to H. Fikentscher in 5% strength by weight aqueous solution at 25.degree. C. and pH 7), are prepared by polymerization of monoethylenically unsaturated monomers in the presence of polymers which in each case contain at least 5% by weight of units of the formulae I and/or II as the grafting base in a weight ratio of from 100:1 to 1:100, and are used as dispersants for pigments, as additives for detergents and cleaning agents, and strength agents for paper and as soil stabilizers and for fertilizer compaction.
摘要:
A process for the preparation of a stable water-in-oil emulsion of a hydrolyzed polymer of an N-vinyl amide of the formula ##STR1## in which R and R.sup.1 denote H or C.sub.1 -C.sub.6 alkyl, by the polymerization of a compound of the formula I alone or in admixture with another ethylenically unsaturated monomer in the presence of a polymerization initiator and emulsifier in the form of a water-in-oil emulsion, to form a water-in-oil polymeric emulsion, followed by hydrolysis of the polymer in the form of the water-in-oil polymeric emulsion in the presence of an acid or base and from 1 to 30 wt %, based on the polymer, of an emulsifier, the emulsifier used being a mixture of (a) from 5 to 95 wt % of a block or graft copolymer of the structure (A-B)m, (A)-B or (B)-A, in which in each case (a) from 5 to 95 wt % of a block or graft copolymer of the structure (A-B).sub.m, (A).sub.n B or (B).sub.n A, in which in each case A is a hydrophobic homopolymer or copolymer having a degree of polymerization of at least 3, B is a hydrophilic homopolymer or copolymer having a degree of polymerization of at least 3, m is equal to or greater than 1, and n is equal to or greater than 2, and (b) from 5 to 95 wt % of another water-in-oil emulsifier having a molar mass below 1000 g/mol.
摘要:
In a cationic modification process for starch, starch is reacted with polymers that contain amino and/or ammonium groups in an aqueous medium at temperatures from 115.degree. C. to 180.degree. C. under an increased pressure and in the absence of oxidizers, polymerization initiators and alkali. The reaction is conducted so that maximum 10% by weight starch has its molar weight reduced. Also disclosed is the use of the thus obtained reaction products as dry strength agents for paper.
摘要:
Graft polymers are obtainable by free radical polymerization of(A) monomers or monomer mixtures comprising(a) from 1 to 100% by weight of N-vinylcarboxamides of the formula ##STR1## where R.sup.1 and R.sup.2 are each H or C.sub.1 -C.sub.6 -alkyl, (b) from 0 to 99% by weight of other monoethylenically unsaturated monomers copolymerizable with the monomers (a) and(c) from 0 to 5% by weight of monomers having at least two ethylenically unsaturated, nonconjugated double bonds in the molecule,in the presence of(B) polymers which contain units of vinyl esters of saturated C.sub.1 -C.sub.4 -carboxylic acids and/or vinyl alcohol units, or of mixtures which contain these polymers and polymers having at least 3 alkylene oxide units or polytetrahydrofuran,in a weight ratio (A):(B) of from 95:5 to 10:90 and, if required, subsequent elimination of the group ##STR2## from the polymerized monomers (I) of the graft polymer with formation of units of the formula ##STR3## and the graft polymers described above are used in the production of paper, board and cardboard as dry and wet strength agents, as retention and drainage aids and as promoters in diketene sizing and as starch cationization agents, as dispersants for pigments and as creping assistants in the production of tissue papers.