Abstract: The invention relates to an electric surface heater, or heating mat, based on an electrically conductive polymer foil or a conductive polymer foam that only heats locally where persons, animals or objects are positioned on the mat. Energy can thereby be saved in comparison with a full-area heater. Ideally, this local heat generation functions without any external electronic control or regulation.

Abstract: New thieno[3,4-b]pyrazine copolymers are prepared by reacting 5,7-functionalized thieno[3,4-b]pyrazines with substituted aromatics in the presence of solvents, bases and polymerization catalysts, the copolymers thus prepared being employed preferably in the production of photovoltaic cells.

Abstract: The invention relates to a flat heater, which is used for applications in the range of heating voltages of up to 1000 V, produces attainable powers of up to 2 kW/m2 and is characterized by the fact that the electrical resistance required for the heating is formed by an electrically conductive cellulose nonwoven. Metallic contacts which are incorporated ensure the connection of the conductive cellulose nonwoven to a voltage source. Polymer films applied on both sides provide mechanical and electrical protection and prevent the ingress of moisture into the cellulose nonwoven.

Abstract: A method and a device for the continuous, single-step production of a homogenous solution of cellulose in hydrous aminoxides on the basis of cellulose and aqueous aminooxides, preferably N-methylmorpholino-N-oxide (NMMO), at temperatures in the range of from 50 to 130° C. under a vacuum and water evaporation. The cellulose and the NMMO are dosed separately to the device, mixed while sheared, the water is evaporated until the mixture is dissolved, the solution is homogenized and directly fed to the consumer via screw conveyors, pumps and filters.

Abstract: Process for producing regular porous pearl cellulose with a particle size in the range from 2 to 1,000 &mgr;m, comprising the steps: a) a cellulose having a degree of polymerisation in the range from 150 to 2,000 is dissolved in a solvent to form a solution of 0.5 to 25% by mass, b) the cellulose solution is finely divided and dispersed in a dispersant which is immiscible with said solution and has a viscosity in the range from 10 to 80,000 mPa·s, c) the dispersed solution particles are solidified to regular pearl particles by precipitating with a liquid precipitating agent miscible with the solvent (1) after cooling the dispersion to below the melting temperature of the cellulose solution and separating the frozen particles of the cellulose solution from the dispersant or (2) directly in the dispersion, and d) the pearl particles are separated from the liquid mixture of solvent, precipitating agent and possibly dispersant.

Abstract: A process for manufacturing molded articles of cellulose, such as fibers films, which includes (a) providing an aqueous solution comprising cellulose in a tertiary amine N-oxide, (b) extruding jets of the aqueous solution through an extrusion die into a non-precipitating medium for cellulose, the extrusion die having nozzle passages the length L of which is in the range from 200 to 800 .mu.m and the capillary section of which has a length l in the range from 50 to 240 .mu.m and a ratio l/d of length l to its diameter d in the range from 0.5 to 2.0, the molecules of cellulose in the jets of solution being pre-orientated by the extrusion die through a shear force gradient in the nozzle passages, (c) additionally orientating the cellulose molecules by stretching the extruded jets of solution in said non-precipitating medium with a spinning stretch ratio V of linear velocity of the precipitated molded article to the linear velocity of the solution leaving the die in the range 0.