Abstract: A thermoreactive recording material contains a dyestuff precursor and an acid-modified polymer of acrylonitrile or methacrylonitrile and a 4-hydroxybenzoic acid ester as acceptor.

Abstract: Triazolopyrimidines of the formula I ##STR1## in which R.sup.1 denotes CN, alkylsulphonyl, arylsulphonyl or arylR.sup.2 denotes H, alkyl or alkythio,R.sup.3 denotes alkyl, aralkyl, substituted aralkyl, alkenyl or alkynyl,R.sup.4 denotes alkyl, aralkyl or aryl, andR.sup.5 denotes alkyl, aralkyl or aryl, orR.sup.4 and R.sup.5, together with the carbon atom, denote a carbocyclic 5-, 6- or 7-membered ring which may be substituted or bridged,in which R.sup.4 cannot be methyl or aryl when R.sup.1 represents CN, R.sup.2 represents H, R.sup.3 represents methyl and R.sup.5 represents methyl or aryl, and in which alkyl preferably has 1-9 C atoms and aryl preferably has 6-12 C atoms, and also a process for their preparation, and their use as initiators.

Abstract: Silica-containing acrylic and modacrylic fibres are obtained without spinning defects in that an aqueous silica sol is reacted with a silane and with a polar organic solvent, the sequence in which the two agents are added being optional, the water is distilled off in a vacuum at a temperature of at most 60.degree. C., the thread-forming polymer is then added in a quantity which is sufficient to form a spinnable solution and the solution is spun.

Abstract: Silica-containing acrylic and modacrylic fibres are obtained without spinning defects in that an aqueous silica sol is reacted with a silane and with a polar organic solvent, the sequence in which the two agents are added being optional, the water is distilled off in a vacuum at a temperature of at most 60.degree. C., the thread-forming polymer is then added in a quantity which is sufficient to form a spinnable solution and the solution is spun.

Abstract: Sulphonic acid-and sulphonate group-containing acrylonitrile polymers are advantageously obtained by precipitation copolymerization in aliphatic hydrocarbons using ethylenically unsaturated sulphonic esters free from carboxylic acid and carboxylic acid ester groups as comonomers and saponifying the sulphonic acid ester groups of the copolymer before, during or after shaping.

Abstract: Polymers obtained by radical polymerization and containing(A) from 0.1 to 80 mole percent of polymerized units corresponding to the following formula ##STR1## in which R.sub.1 represents hydrogen or methyl,R.sub.2 represents alkyl, particularly primary or secondary alkyl containing from 1 to 4 carbon atoms, andR.sub.3 represents hydrogen or alkyl, particularly primary or secondary alkyl containing from 1 to 4 carbon atoms, and in which the sulphonic acid group may be present in the form of a salt, and(B) from 20 to 99.9 mole percent of polymerized units of one or more ethylenically unsaturated monomers, are particularly suitable for the production of filaments, fibres and films having a high absorption capacity for basic dyes.

Abstract: The title compounds are obtained by reacting compounds corresponding to the following formula:R.sub.1 --CH.dbd.CH--CO.sub.2 R.sub.2wherein R.sub.1 represents hydrogen or a methyl group and R.sub.2 represents a primary or secondary C.sub.1 to C.sub.4 alkyl group, with from 0.6 to 1.6 mol. equivalents of SO.sub.3 and, optionally, with from 0.1 to 10 mol. equivalents of an alkylating agent at temperatures in the range from -10.degree. to +25.degree. C., subsequently heating the resulting reaction mixture for 0.5 to 6 hours to 70.degree.-200.degree. C. and then working it up by distillation.

Abstract: It is possible to remove quantities of heat from exothermically running polymerization reactions of vinyl monomers in heterogeneous phase, in a sophisticated manner by adding liquids to the reaction medium for the removal of heat and to regulate the reaction temperature, which liquids do not dissolve the polymer under the reaction conditions and the boiling temperatures of which are lower than or are identical to the technically predetermined reaction temperatures under the polymerization conditions which are applied, and the heat which is released in the reaction system is removed by evaporating these liquids.

Abstract: This invention relates to a process for the graft polymerization of (A) from 95 to 40 parts, by weight, of at least one ethylenically unsaturated monomer in the presence of (B) from 5 to 60 parts, by weight, of a partially or completely cross-linked rubber, in which the one or more than one monomer (A) and rubber (B) in the form of a latex or of a dispersion in an organic solvent are polymerized in an aliphatic hydrocarbon as reaction medium at from 30.degree. to 100.degree. C., using a radical forming initiator, and the graft polymerization product obtained as a sedimenting suspension of particles having an average diameter of from 5 to 1,000 .mu.m is isolated.

Abstract: Acrylonitrile polymers and copolymers with good affinity for basic dyes without sulfonic acid groups containing comonomers are obtained by polymerizing at a temperature of from 0.degree. to 60.degree. C. in an aliphatic hydrocarbon having a boiling point of from -10.degree. to 80.degree. C. or in a mixture of aliphatic hydrocarbons having boiling points in the range from -10.degree. to 80.degree. C. using an initiator system comprising from 0.1 to 8.0 mole percent of sulfur dioxide, from 0.1 to 2.0 mole percent of a hydroperoxide which is soluble in the reaction medium and from 0.01 to 1.0 mole percent of an acid which is soluble in the reaction system in that polymerization is carried out continuously and in that an average residence time of from 10 minutes to 2 hours is maintained.

Abstract: The invention relates to a homopolymer or copolymer of acrylonitrile which comprises from 0 to 30% by weight, incorporated by polymerization, of comonomer units which are free from ionic groups, said polymers having a K-value of from 50 to 100, a dye absorption capacity for cationic dyes of at least 0.5% by weight, a conductivity, measured in dimethylformamide solution, of at least 10.mu. Siemens, and from 0.2 to 1.5% by weight of sulphur fixed to said polymer as well as to a process for the production thereof.

Abstract: The invention relates to a process for the production of polyacrylonitrile or acrylonitrile copolymers, the polymerization being carried out at a temperature of from -40.degree. to +60.degree. C. optionally under pressure in an aliphatic chlorofluorine or fluorine substituted hydrocarbon containing up to 8 carbon atoms and having a boiling point of from -60.degree. to +50.degree. C. or in mixtures thereof having boiling ranges of from -60.degree. to +50.degree. C. and using a starter system comprising a hydroperoxide sulphur dioxide and an acid. The system may also contain aliphatic hydrocarbons in such quantities that a non-inflammable mixture is formed.

Abstract: A thermoplastic moulding composition with improved flow properties being workable without difficulty by extrusion, injection moulding or blow moulding and resulting in colorless, transparent products with a smooth, glossy surface, comprising a mixture of(A)90 to 99.9% by weight of a polymer with a K-value of from 50 to 80, as measured at a temperature of 25.degree. C. in dimethyl formamide on a 0.5% by weight solution, which contains at least 50% by weight of acrylonitrile or methacrylonitrile or a mixture thereof in polymerized or grafted form, and(B)0.1 to 10% by weight of a statistical copolymer of copolymerized units of65 to 85% by weight of at least one acrylic acid alkyl ester with 1 to 8 carbon atoms in the alcohol component, and15 to 35% by weight of styrene,The copolymer B having an intrinsic viscosity [.eta.] of from 2.9 to 13.0 dl/g, as measured at 25.degree. C. in tetrahydrofuran.

Abstract: Acrylonitrile/vinyl acetate/styrene copolymers containing a high proportion of acrylonitrile (50-80% by weight) which undergo no discoloration and result in highly transparent products when thermoplastically processed are produced by continuous emulsion copolymerization the monomers in a tube reactor in which comparatively little back mixing occurs (plug flow = laminar flow = non-stationary state).

Abstract: The invention relates to wet-spun modacrylic filaments with improved coloristic properties based on a polymer mixture, which comprises at least one acrylonitrilevinyl chloride copolymer and a chlorine-containing copolymer containing sulphonic acid ester groups or sulphuric acid ester groups.

Abstract: The invention relates to dry-spun modacrylic filaments with improved coloristic properties based on a polymer mixture, which comprises at least one acrylonitrile-vinyl chloride copolymer and a chlorine-containing copolymer containing sulphonic acid ester groups or sulphuric acid ester groups.

Abstract: Vacuole-free films, filaments and fibers consisting of a polymer mixture which comprises a copolymer of acrylonitrile and a polymer which is obtained by a polymer-analogue reaction of a polyacrylic acid ester with dimethylamine, said polymer containing from 40-99 mol % of N,N-dimethyl acrylamide units.