Hoechst Aktiengesellschaft

Walter Fester

Bernd Huber

Ernst-August Albers

Rolf Kleber

Kasimir Ruchlak

Erhard Leicht

Reinhart Mayer

Georg Michael Lorenz

Ulrich Schuster

Bernd Sassenrath

Dirk Theis

Gerhard Schmidt

Lieselotte Wappes

Ralph Sch Afer

The ski described is characterized by the use of a selected fiber reinforced material comprising a sheetlike textile material and a thermoset resin, the fiber content being 30-70% by weight and the fiber being not less than 30% by weight synthetic. This material is notable for high flexibility and high restoring forces and confers excellent properties on the ski, for example good vibration damping.

Ski containing sheetlike plates or tapes made of a fiber reinforced

There is described a tampon made of continuous filaments based on a man-made fiber tow with a water-holding capacity of at least 1000% by weight, the tampon consisting essentially of continuous filaments in a perpendicular arrangement relative to the longitudinal axis of the tampon with essentially only one free filament end at the surface per filament while the other free filament end is on the inside.

Tampon and manufacture thereof

Monofils and bristles which comprise at least 90% by weight of acrylonitrile units and have a linear density of more than 2.5 tex possess a relative solution viscosity of 1.7 to 6.0, a tear strength of at least 20 cN/tex and an initial modulus of more than 700 cN/tex. The manufacturing process is distinguished by a wet stretch of the spun filaments by at least 1:4, drying under tension and a subsequent hot stretch of at least 1:2, the overall stretch being at least 1:8, preferably 1:10 to 1:20. The monofils and bristles according to the invention are suitable in particular for producing filament-reinforced composite materials.

Monofils and bristles of homopolymers or copolymers of acrylonitrile,

The invention relates to filaments and fibers spun from at least 98% by weight of polyacrylonitrile and relative viscosities of between 2.5 and 6.0 which have tensile strengths of more than 50 cN/tex with an elongation at break of at most 15% and a shrinkage at the boil of less than 5% and to a process for their production which comprises at least 2 stretching stages with a minimum stretching ratio of 1:9 as well as a concluding setting stage in which the filaments are treated without shrinkage in dry heat at 170.degree. to 280.degree. C. Such filaments and fibers are distinguished by an increased resistance to swelling and hydrolysis and they are particularly suitable for reinforcing organic and inorganic materials.

Process for production of set polyacrylonitrile filaments and fibers

The invention relates to continuous processes for preparing dimethylformamide-insoluble acrylic filaments and fibers which incur a weight loss of at most 20, preferably 15% on being heated up to 400.degree. C., by spinning appropriate polymer solutions, treating the filament bundles obtained before the first drying or heating stage in a continuous manner with an aqueous solution containing copper(I) ions, thermally fixing the copper content, and heating the bundles to 200.degree. to 350.degree. C.

Processes for preparing thermostable fibers and filaments

The invention relates to a process for preparing wet- or dry-spun filaments and fibers of polymers which consist to more than 50% by weight of acrylonitrile units and which are continually treated with an aqueous solution containing copper(I) ions during the fiber production process but before a first heat treatment above 100.degree. C. and the copper content in the fibrous material is fixed by heating to above 60.degree. C., preferably to above 100.degree. C. The filaments and fibers thus obtained can be dyed with acid dyestuffs, have bactericidal properties, and can be subjected to accelerated pre-oxidation.

Process for preparing acrylic filaments and fibers

Set polyacrylonitrile filaments and fibers, and a process for their

The invention relates to flame-retarding filaments and fibers and a process for the manufacture thereof. The filament-forming substance is a mixture of from 20 to 70 weight % of an acrylonitrile copolymer A containing at least 80 weight % of acrylonitrile units and from 0.3 to 20 weight % of other units copolymerizable with acrylonitrile, and from 80 to 30 weight % of an acrylonitrile copolymer B containing from 50 to 75 weight % of acrylonitrile units, from 25 to 45 weight % of vinyl chloride and/or vinylidene chloride units and from 0 to 5 weight % of other units copolymerizable with acrylonitrile. The filaments and fibers have a boil-off shrinkage of at least 20% and a knot strength of at least 10 cN/tex and are obtained by spinning the turbid solutions of the copolymer mixture, which however do not separate into components, in an aprotic solvent, and drawing of the filaments in a moderate ratio.

Filaments and fibers of acrylonitrile copolymer mixtures

The invention provides a process for the manufacture of viscoses from hemicellulose-containing cellulose pulps without requiring dialysis equipment. By addition of substances having a cross-linking or blocking action on the active groups of hemicellulose to the pulp before or during steeping it is possible to reduce the use of NaOH and CS.sub.2 in the manufacture of viscoses. The viscoses so obtained are distinguished by good filterability and low content of compounds causing formation of H.sub.2 S in the spinning process.

Process for the manufacture of viscoses

The invention relates to modacryl filaments and fibers made from copolymers insoluble in acetone of acrylonitrile and from 20 to 45 weight % of vinylidene chloride, containing from 0 to 1.5 weight % of unsaturated organic sulfonic acids or the salts thereof, and from 0 to 10 weight % of further copolymerizable compounds, which copolymers have a K value according to Fikentscher of from about 60 to about 90, and a process for the manufacture thereof. These modacryl filaments and fibers are especially distinguished by their permanent brilliance and permanent transparence; these properties are maintained even on contact with water having a temperature above 80.degree. C.

Modacryl filaments and fibers and process for their manufacture

The present invention relates to a vessel and a process for polymerizing vinyl chloride in suspension. The vessel the inner surfaces of which consist of stainless steel or are plated with a noble metal comprises at least one cathode in contact with the reaction medium and insoluble therein and as anode the metallic inner surface of the vessel, the cathode and anode being connected over an external source of current. The polymerization is carried out with electrolytic generation of hydrogen and oxygen from the polymerization medium. The polymerization vessel and process according to the invention suppress completely or substantially the formation of wall deposits.

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Konigstein, Germany

Walter Fester