Abstract: An improvement in the process of producing polyvinyl chloride by the suspension process in the presence of protective colloids by utilizing a protective colloid mixture of from 20% to 80% of the protective colloid mixture of a polyvinyl acetate having a hydrolysis degree of 40 to 55 mol % and the remainder of the protective colloid mixture of (1) a water-soluble polyvinyl alcohol having a hydrolysis degree of 70 to 90 mol %, or (2) an aminoethyl-hydroxypropyl cellulose having a molar substitution of from 0.05 to 1.5 mols of aminoethyl groups and 3 to 5 mols of hydroxypropyl groups, or (3) a vinyl acetate/vinyl pyrrolidone copolymer having a ratio of vinyl pyrrolidone to vinyl acetate in the copolymer of 50% to 70% by weight to 30% to 50% by weight and a K-value of 25 to 40. By the use of this protective colloid mixture, the polyvinyl chloride produced exhibits a large absorption of plasticizer and gives finished products having a low number of specks.

Abstract: A polymerization autoclave for the suspension polymerization of vinyl compounds in the aqueous phase having a volume of from 50 to 200 m.sup.3, an impeller agitator driven from below at the bottom of the autoclave and two cylindrical displacement bodies acting as flow interrupters, secured downwardly from the autoclave dome, where the autoclave has a height-to-diameter ratio of from 2.4 to 3 with a critically dimensioned agitator and critically dimensioned flow interrupter fittings. By the use of this invention in the case large-scale autoclaves, the heat of polymerization can be removed merely by wall-cooling. The autoclave according to the invention are very economical, as shown by, for example, a spatial capacity of 0.3 to 0.4 metric tons of polyvinyl chloride per m.sup.3 autoclave volume.

Abstract: A contact bridge arrangement useful particularly in electromagnetic switchgear has a set of fixed contacts and a contact bridge which can be brought into active connection therewith. The contact bridge is movably guided in a window of a contact bridge carrier being spring loaded in the direction of the fixed contacts by a spring which is braced on a support part which is carried, in the active position, on parts fixed to the housing and which is elevated by a stop in the window of the contact bridge carrier. The support part is inserted between a spring cup and the stop in the window of the contact bridge carrier from the outside of the contact bridge assembly in a direction transverse to the direction of the spring loading.

Abstract: In the process for steam-stripping residual monomer from an aqueous polymer dispersion comprising injecting steam into an aqueous polymer dispersion containing residual monomers and the customary amounts of emulsifiers and/or protective colloids, said dispersion having a solids content of from 15% to 55% by weight with simultaneous evacuation of the gas space above the dispersion whereby said gas space is maintained at a subatmospheric pressure and said residual monomers are volatilized, the improvement consisting of injecting a sufficient volume of steam into said aqueous polymer dispersion whereby from 5% to 50% by weight of the injected steam passes through said dispersion uncondensed, thereby substantially preventing formation of foam above said dispersion.

Abstract: A process for the manufacture of vinyl chloride copolymers soluble in lacquer solvents with a clear solution consisting of copolymerizing vinyl chloride and at least one other olefinically-unsaturated compound copolymerizable with vinyl chloride under suspension copolymerization conditions in an aqueous dispersion and in the presence of (a) a monomer-soluble polymerization catalyst, (b) a water-soluble salt of a maleic acid anhydride mixed polymerizate of maleic acid anhydride, an olefinically unsaturated ester or ether of at least 7 carbon atoms, and another vinyl monomer, (c) from 0.003% to 0.007% by weight of a polyvinyl alcohol having a low viscosity and a high saponification number and (d) from 0.03% to 0.05% by weight of sodium chloride, whereby a vinyl chloride copolymer is obtained having the majority of its particles of a size between 0.1 and 0.5 mm.

Abstract: An improved electromagnetic switching apparatus including a housing, a plurality of movable contact bridges mounted on a contact bridge carrier, first fixed contact elements which extend around one end of the contact bridges and are coupled to terminal elements for the first fixed contact elements, and electrically-separated second fixed contact elements disposed at the other end of the contact bridges on both sides thereof. The improvement of the invention comprises the provision of means for selectively electrically connecting the second fixed contact elements to a common terminal element.

Abstract: An electromagnetic switching apparatus including a housing, movable contact elements mounted on a plurality of contact bridges in the housing, electrically-connected fixed contact elements disposed on both sides of the contact bridges adapted for contact and electrical connection with the movable contacts and the contact bridges, and electrical insulation means for interrupting the electrical connection between the fixed contact elements and the contact bridges in two terminal positions of the contact bridge carrier. The improvement comprises at least one end of the contact bridges extending outwardly beyond the area of contact between the movable contacts and the fixed contacts. The electrical insulation means are movably supported in the switching apparatus housing so as to be operatively engageable in at least one position with the extended ends of the contact bridges for interrupting the electrical connection between at least one of the contact bridges and the fixed contact elements.

Abstract: An improvement in the suspension polymerization of a polymerizate containing at least 90% polyvinyl chloride by the steps of mixing monomers selected from the group consisting of vinyl chloride and mixtures of vinyl chloride with up to 10% of olefinically unsaturated compounds copolymerizable with vinyl chloride, with water in the presence of a polymerization catalyst and suspension stabilizers, heating said mixture under continuous agitation to polymerization temperatures and recovering said polymerizate. The improvement comprises utilizing a gas containing molecular oxygen as the sole catalyst or catalyst-forming substance. The so-prepared polymerizate forms sheets with a lower content of "fish eyes" and a greater heat stability.

Abstract: A method of reducing the electrostatic charge aquired by a plastic composition by incorporating therein an antistatically effective amount of a mixed oxide of phosphorus and one or more metals selected from the group consisting of silicon, aluminum, titanium and iron, said mixed oxide having been prepared by flame hydrolysis; as well as the plastic composition containing said mixed oxide.

Abstract: An adhesion assistant or binder composition for bonding polyolefin surfaces with metal surfaces comprising an aqueous dispersion of an ethylene/vinyl acetate copolymer from 0.5 to 5 parts by weight based on 100 parts of the copolymer of a cross-linking peroxide compound and from 1 to 10 parts by weight based on 100 parts of the copolymer of a low-molecular-weight 1,2-polybutadiene; as well as a process for producing composite bodies by heat and pressure utilizing the above adhesion assistant between polyolefin surfaces and metal surfaces.

Abstract: In the housing of an electromagnetic switching apparatus including a magnet coil and switching and non-switching magnet parts disposed within the housing, and at least one damping compression spring for biasing the non-switching magnet part in one direction in the housing, the spring having a plurality of turns of the same diameter and one end turn having a diameter greater than that of the plurality of turns for securing the spring in the housing, the improvement comprising hook-shaped projection members disposed within the housing about the periphery of the compression spring. The projection members are spaced apart from each other along a diameter of the spring by a distance which is greater than the diameter of the plurality of turns thereof but less than the diameter of the end turn. The plurality of turns of the spring are axially movable between the projection members while the end turn of the spring is engaged by the members.

Abstract: A readily dryable adhesive binder for particulated rubber and/or plastics compositions comprising from 1% to 10% by weight of a water-solubleformaldehyde polycondensation resin, from 0.5% to 5% by weight of formaldehyde or a compound liberating formaldehyde, and from 85% to 98.5% by weight of a film-forming plastics dispersion; as well as a composition forming a resilient covering comprising from 40% to 75% by weight of particulated rubber and/or plastics and from 25% to 60% by weight of the above adhesive binder.

Abstract: An electrical equipment apparatus which includes an equipment housing and at least one slidable mounting member for fastening the equipment to a support rail. The member is guided by guide keys provided in the equipment housing and includes a compression spring disposed in a longitudinal recess thereof which engages the member at one end and the equipment housing at the other. Barb-like, resilient stop members are formed on the mounting member and extend transversely with respect to the direction of movement thereof, and are received by recesses in the equipment housing for limiting the movement of the mounting member and equipment with respect to the housing.

Abstract: A process for the production of polyvinyl chloride graft copolymers from ethylene/vinyl acetate copolymers and vinyl chloride by graft polymerization in the aqueous phase consisting essentially of adding a water-soluble, free-radical-forming polymerization catalyst to an aqueous dispersion of an ethylene/vinyl acetate copolymer optionally containing additional emulsifiers and/or dispersion stabilizers, heating said dispersion to the polymerization temperature, adding vinyl chloride gas above said agitated heated dispersion at such rate that the pressure is below the saturation pressure of vinyl chloride at the polymerization temperature, and recovering said polyvinyl chloride grafted copolymer.

Abstract: An impact resistant thermoplastic molding composition comprisingA. 80% to 98% by weight of polyvinyl chloride,B. 2% to 20% by weight of a modifying resin for improving the impact strength, characterized by an additional content of,C. 2% to 30% by weight, based on PVC, of a coated calcium carbonate, the surface of which has been treated with stearic acid and which has a particle size of 0.04 to 0.1 .mu..The composition is useful for preparing shaped articles, such as hollow articles.

Abstract: Impact-resistant molding compositions consisting essentially ofA. from 20% to 80% by weight of polyvinyl chloride having a K-value of from 55 to 70,B. from 19.5% to 75% by weight of a vinyl chloride grafted copolymer of ethylene and vinyl acetate, said copolymer having from 30% to 55% by weight of vinyl acetate monomer units and a Mooney viscosity of from 20 to 50, said vinyl chloride grafted copolymer having from 5% to 15% by weight of said copolymer and a K-value of from 55 to 70, andC. from 0.5% to 5% by weight of an ethylene/vinyl acetate copolymer having from 60% to 70% by weight of vinyl acetate monomer units.

Abstract: An apparatus for the production of extruded profiles of foamed thermoplasts consisting of an extruder having an extrusion screw or helix and a form-giving extruder head having a flow channel there-through, at least part of the length of said flow channel being divided by separating walls having a thickness of 0.2 to 3 mm arranged in the axial direction into individual channels of such a length and cross-section area whereby each individual channel has a nozzle coefficient k of from 0.1 to 2mm.sup.3, characterized in that thorn-like pins are inserted into some of the individual channels; as well as the process of extrusion.

Abstract: Vinyl chloride terpolymers soluble in aromatic compounds with a K-value of from 25 to 38, measured in cyclohexanone consisting of an emulsion polymerized monomer mixture of from65% to 80% by weight of vinyl chloride,15% to 27% by weight of a diester of maleic acid and/or fumaric acid with multiple-branched alkanols having 9 to 15 carbon atoms, and3% to 15% by weight of a monoester of maleic acid and/or fumaric acid with multiple-branched alkanols having 9 to 15 carbon atoms;As well as the process of their preparation by pre-emulsification of the mono and di esters in the aqueous phase with an anionic emulsifier prior to polymerization with vinyl chloride.