Abstract: The disclosure of this application is directed to a composition, devoid of added mineral filler, comprising an ethylene polymer and an organo titanium chelate as a water treeing inhibitor. The compositions can be extruded about electrical conductors providing insulation thereon which is resistant to deterioration in the presence of moisture and/or an electrical field.

Abstract: A heat distortion-resistant thermoplastic semi-conductive composition which includes ethylene-vinyl acetate and/or an ethylene acrylate ester copolymer, and an admixture of high density polyethylene and linear low density polyethylene in addition to the electrically conductive component and other additives normally forming part of such compositions.

Abstract: A mixture of substances is fed to an extruder and, after being homogenized and liquefied, is extruded on an electric conductor or as a pipe. To meet electric cable specifications, the insulating material used is a polyolefin, such as polyethylene, cross-linking of which is brought about by the addition of a silane, a free-radical generator, and a silanol condensation catalyst. After extrusion, cross-linking takes place in the presence of moisture. To facilitate penetration of the moisture and accelerate cross-linking, an agent capable of reducing the rate of crystallization of the polymer, such as vinyl acetate, is used as a further additive.

Abstract: Track and erosion resistant electrical insulating materials are disclosed comprising (a) a base insulating material comprising a polymer of ethylene and additives necessary to allow the polymer to function as electrical insulation, and (b) hydrated zinc borate as an anti-tracking and anti-erosion additive. The hydrated zinc borate functions to increase the track and erosion resistance of the electrical insulating material in concentrations of as little as 1% by weight of the entire material with its maximum effect being achieved at concentrations of about 25% by weight of the entire material.

Abstract: A method for stabilizing organic polymers against copper-catalyzed oxidative decomposition by means of N,N-bis-salicyloyl hydrazine as a metal deactivator is described wherein dust development of the metal deactivator is precluded with certainty and negative property changes of the stabilized organic polymers are avoided. For this purpose, it is provided that a paste which contains finely-crystalline N,N'-bis-salicyloyl hydrazine in fine distribution in a liquid to wax-like aliphatic hydrocarbon of low volatility is worked into the polymer. The method is particularly well suited for stabilizing polyolefins for cable and wire insulation.

Abstract: An extrusion process for the manufacture of insulated winding wires. Part crystalline thermoplastic polycondensates with crystallite melting points above 170.degree. C., preferably above 250.degree. C., are extruded. Polyethylene terephthalate is the polycondensate of choice. These are filled with 5-15% by weight titanium dioxide. The result is the avoidance of fissure formation.

Abstract: An unfilled polymeric composition having improved electrical treeing and water treeing properties comprising a polymeric component and effective amounts of a hydrocarboxyalkoxy silane and a fatty acid. These compositions are particularly useful as insulation for high voltage transmission and distribution cables.

Abstract: Tracking is reduced in insulators comprising one or more polymers and an anti-tracking filler system comprising (a) a hydrate of alumina having a specific surface area of at least 2 m.sup.2 /g measured by the BET method, and (b) a compound selected from the group consisting of oxides, mixed oxides and mixtures of oxides wherein said compound contains at least one element selected from the group consisting of transition series elements, lanthanide series elements and nontransuranic actinide series elements.

Abstract: A novel flame-retardant ethylene polymer composition comprising a copolymer consisting essentially of ethylene and an olefinically unsaturated silane compound such as vinyltriethoxysilane, a silanol condensation catalyst such as dibutyltin dilaurate, and a flame retardant such as a chlorinated polyethylene.

Abstract: Compositions, devoid of fillers, comprising an ethylene polymer and an N-phenyl substituted amino silane, which can be extruded about electrical conductors to provide insulation thereon which is resistant to the formation of water trees.

Abstract: A composition of high oxygen index that yields little visible smoke and little or no corrosive fume on combustion and having adequate mechanical and electrical properties for cable jackets and bedding comprises;20-35 parts of ethylene-vinyl acetate copolymer;52-75 parts of an alumina trihydrate with at least half its weight in particles with a diameter in the range 0.5-3.0 micrometer;up to 3 parts of stearic acid or a stearate; andat least one antioxidant and if desired at least one curing agent in effective amounts not exceeding 4 parts in all.A double-layer of aromatic polyimide tape, the first layer helically lapped and the second preferably longitudinally applied, is interposed between a bedding an a jacket both of the above composition to give a superior low-smoke cable for use in tunnels of railroads or other transportation systems.

Abstract: A polyolefin insulated electric cable exhibiting the effect of suppressed water tree formation which comprises an electrical insulation layer comprising a polyolefin containing about 0.01 to 13.0% by weight ester groups provided around a conductor.

Abstract: The disclosure of this application is directed to a composition, devoid of added mineral filler, comprising an ethylene polymer and an organo titanate as a water treeing inhibitor. The compositions can be extruded about electrical conductors providing insulation thereon which is resistant to deterioration in the presence of moisture and an electrical field.

Abstract: A product by process for reducing micro-voids in cross-linked cable insulation without reducing the voltage breakdown strength thereof in which process the insulation, after cross-linking, is heated at a temperature in the range from about 120.degree. C. to about 150.degree. C. and under a pressure less than 10 mm. Hg for a period from about 8 hours to 48 hours. Also, a cable having such insulation which has micro-voids less than about 10.sup.2 per mm.sup.3 and a perforation gradient greater than the perforation gradient of a cable which has not been so treated.

Abstract: A process for producing a highly expanded polyolefin insulated cable comprising the steps of feeding a compound of polyolefin, nucleating agent and volatile liquid to an extruder, heat extruding said compound through said extruder onto an inner conductor passing through said extruder to cover the outer periphery of said inner conductor thereby forming an insulation layer of highly expanded polyolefin foam having a foaming ratio in excess of 2.5 times (60% expansion degree) tightly adhered to said inner conductor.

Abstract: A high voltage cable comprising a conductor and a polythene containing insulation sheath is provided with a metal complex of a diketone, salicylic acid optionally substituted with 1 to 2 lower alkyl groups, or a Schiff's base formed from an amine and salicylaldehyde optionally substituted with 1 to 2 lower alkyl groups, in order to prevent or impede the growth of watertrees during use.

Abstract: New polymeric compositions based on polytetramethylene terephthalate (PTMT) polymers are disclosed. PTMT polymers are subject to embrittlement, especially at elevated temperatures and when a flame retardant is incorporated therein. This problem is substantially reduced by blending the PTMT polymer with a second polymer which has a flex modulus of 500 to 100,000 psi and a solubility parameter within .+-.1.5 of the PTMT polymer, for example an ethylene/vinyl acetate copolymer or a block copolymer containing polyether and polyester blocks. The compositions are particularly useful as wire insulation.

Abstract: An improved means of making an electrical connection to a laminar electrode which is in contact with a conductive polymer element. A mat of conductive filaments is placed between the electrode and an apertured conductive member to which the electrical connection is made, and the electrode, the mat and the conductive member are bonded together by means of a polymer or other bonding agent. The presence of the mat between the electrode and conductive member reduces the danger of fracturing the electrode when the conductive member is bonded thereto by heat and pressure. The invention is particularly useful when an ultrasonic welding machine is used to press the conductive member through a layer of polymer to make contact with an electrode underneath the layer.

Abstract: The invention concerns a novel cladded elongate substrate such as a jacketed cable, the cladding being flame retarded and comprising a vinyl acetate/alkene copolymer composition incorporating a halogen-free inorganic flame retardant. The composition is characterized by a high content of vinyl acetate and/or the presence of a polyalkene or alkene/alkene copolymer blended with the vinyl acetate/alkene copolymer.

Abstract: This specification relates to a communication cable and method of making it, particularly where the cable includes a high pair count with small conductors so that the filling compound can be made to permeate to the center of the cable without having the filling compound become too viscous to reach the center of the cable when filled by the liquid filling process. The filling compound does not drip at temperatures up to 90.degree. C. From five to ten parts by weight are used of a polyethylene compound as one ingredient of the filler material. The major ingredient of the filler is a paraffinic oil which constitutes 100 parts of the filler compound. Other important considerations are to formulate the compound so that it will not permeate into the cells of the foam skin or all foam insulation.

Abstract: Insulation for an electric power cable, and a power cable including such insulation, the insulation having an improved dielectric strength and being irradiation cross-linked polymeric material having mixed therewith carbon black having a particle size in the range from about 200 to about 500 millimicrons, the carbon black content being about 10% to about 40% of the weight of the mixture of carbon black and the polymeric material. Also, the cable insulation may be layers of different density polyethylene, at least one of the layers being the described mixture of polyethylene and carbon black.

Abstract: The invention relates to novel electrical devices which are useful for example as heaters and temperature sensors, and which comprise at least two electrodes, at least one PTC element, at least one relatively constant wattage element, and at least one current-directing element which directs the current, when the device is first connected to a source of electrical power, so that the effective initial resistance of the device is greater than it would be in the absence of said element. Thus the invention provides a solution to the problem of current inrush in application of PTC devices in which substantial current passes through the device at operating temperatures. The invention also includes the use of the novel devices in applications in which current inrush is not a problem.

Abstract: A polyolefin composition for electrical insulation which comprises polyolefin or crosslinked polyolefin and a small quantity of high-molecular weight polyethylene glycol. This composition is far less vulnerable to the deterioration that occurs as dendroid voids when employed as an electrical insulation of high-tension power cables which are operated under water. The polyethylene glycol has more than 44 carbon atoms and is used in an amount from 0.3 to 10 wt % based on polyolefin.

Abstract: A unfilled polymeric composition having improved electrical treeing and water treeing properties comprising a polymeric component and effective amounts of an organic compound, such as, a specially defined silane. These compositions are particularly useful as insulation for high voltage transmission and distribution cables.

Abstract: A composition is disclosed especially useful for high voltage electrical insulation comprising a blend of polyethylene, an alcohol of 6 to 24 carbons to prevent electrical failure, and polypropylene to mitigate exudation of the alcohol.

Abstract: This invention is an improved insulation for electric cables and an improved method of making the insulation. Cross linked polyethylene insulation is too stiff, particularly in high voltage cables which require a thick layer of insulation. Copolymers of polypropylene have electrical properties substantially equal to those of polyethylene, but do not have the necessary physical strength and have to be filled with clay or other filler that provides the required strength but degrades the electrical characteristics. A novel feature of this method is the utilization of the screw of the extruder to effect a mixing of the ingredients in an improved polymer system for cable insulation.

Abstract: Electrical insulation for an elongate current carrying body, e.g. an underwater cable for carrying very high voltages, is provided by winding a tape round the body under tension, the tape being made of a film of an axially orientated polymer having a thickness less than 200 microns, and preferably between 10 and 50 microns, a significant degree of crystalline order, a high tensile strength, a high modulus of elasticity, and the ability to cling to itself.

Abstract: A dielectric composition comprising ethylene polymer and effective amounts, as a water treeing inhibitor, of at least one organo silane of the following formula: ##STR1## wherein R and R.sub.1 are independently selected from hydrogen, a hydrocarbyl group or substituted hydrocarbyl groups wherein the substituents are hydroxy, halogen, nitro, C.sub.1 to C.sub.8 alkyl, C.sub.1 to C.sub.8 alkoxy; or R and R.sub.1 together with the adjacent carbon atom form a ring of 3 to 7 carbon atoms; R.sub.2 is C.sub.1 to C.sub.8 alkyl, C.sub.1 to C.sub.18 alkoxy, C.sub.6 to C.sub.18 aryl, C.sub.1 to C.sub.8 acyloxy, C.sub.6 to C.sub.18 substituted or unsubstituted aryloxy; R.sub.3 and R.sub.4 are independently selected from C.sub.1 to C.sub.18 alkoxy, C.sub.6 to C.sub.18 substituted or unsubstituted aryloxy or C.sub.1 to C.sub.8 acyloxy; Y is C.sub.1 to C.sub.8 alkylene, C.sub.6 to C.sub.18 substituted or unsubstituted arylene or --CH.sub.2 CH.sub.2 NH(CH.sub.2).sub.3 --.

Abstract: Polyolefin compounds having improved resistance to oxidation and heat aging attributable to the incorporation therein of the combination of a zinc salt of a mercaptoimidazole with a sterically hindered phenol, a method of enhancing oxidation resistance and heat aging stability by means of the incorporation of the combination in polyolefins, an electrical conductor insulated therewith and method of forming.

Abstract: A process for reducing micro-voids in cross-linked cable insulation without reducing the voltage breakdown strength thereof in which process the insulation, after cross-linking, is heated at a temperature in the range from about 120.degree. C. to about 150.degree. C. and under a pressure less than 10 mm. Hg for a period from about 8 hours to 48 hours. Also, a cable having such insulation which has micro-voids less than about 10.sup.2 per mm.sup.3 and a perforation gradient greater than the perforation gradient of a cable which has not been so treated.

Abstract: Petrolatum-based filling compounds are known to migrate into the insulation and jacket of telephone cables and to extract the stabilizers, and as a consequence, to affect the physical and/or electrical characteristics of those cable components. It does not seem possible to avoid these characteristics of petrolatum in commercial compounding operations. The filling compound of this specification is for use in telephone cables and is based on better resistance to dripping at elevated temperatures, compatibility with high density polyethylene insulation and low density and medium density polyethylene jacket compounds. It has processability at moderate elevated temperatures, resistance to cracking at room temperature and low temperatures, adhesiveness and desirable electric properties.

Abstract: The invention relates to novel electrical devices which are useful for example as heaters and temperature sensors, and which comprise at least two electrodes, at least one PTC element, at least one relatively constant wattage element, and at least one current-directing element which directs the current, when the device is first connected to a source of electrical power, so that the effective initial resistance of the device is greater than it would be in the absence of said element. Thus the invention provides a solution to the problem of current inrush in applications of PTC devices in which substantial current passes through the device at operating temperatures. The invention also includes the use of the novel devices in applications in which current inrush is not a problem.

Abstract: A composition for enhancing and maintaining mechanical properties such as tensile strength of an ethylene polymer on heating at elevated temperature comprises (A) an initiator of cross-linking having a half-life measured at 110.degree. C. of 0.1 to 50 hours and (B) an alkylthioalkylenecarboxylic acid ester of a polycarbocyclic polyhydric phenol.

Abstract: Materials and methods are shown for increasing the antioxidant protection of polyolefin insulation, such as low density polyethylene insulation on electrical conductors. The materials may be applied in the field to increase the service life of in-place cable. The material is typically applied by brushing or spraying a lacquer-based carrier containing the inventive stabilizer onto the insulation to be protected. The stabilizer migrates into the polyolefin insulation, typically increasing the service life of antioxidant depleted cable by several years.

Abstract: In cables where the conductor is provided with an insulation of thermoplastic or cross-linked polyethylene, the insulation may be covered with a strippable outer semiconductive layer consisting of a cross-linked polymer composition which comprises a copolymer of ethylene and vinyl acetate and further carbon black and an organic peroxide. The strippable layer is applied on the conductor insulation by extrusion of the polymer composition in an extrusion machine and by a subsequent crosslinking in the polymer composition.

Abstract: This telephone service wire has metal conductors insulated with polyethylene plastic insulation or equivalent, assembled in a core having a flame-retardant polyvinyl chloride jacket. Space between the individual insulated conductors is filled with an improved filling compound for preventing access of water into the core of the service wire. The filler compound is an ester-based compound that avoids the disadvantages of the usual petrolatum-based filler compound which extracts not only antioxidants and copper-inhibitors from a polyethylene component but plasticizers from a polyvinyl chloride compound. Depletion of these essential compounding materials can seriously affect the physical characteristics of either the insulation or jacket of such filled telephone service wires.

Abstract: The electrical properties of polymeric dielectric materials or compounds including polar additives are enhanced by a method of treating the polar additives with a reactive silicone liquid, and the improved polymeric insulation products of the method.

Abstract: Insulation particularly suitable for high voltage power cable consists essentially of low density polyethylene (or crosslinked polyethylene) and an effective amount of an alcohol of 6 to 24 carbon atoms which is a tree growth inhibitor capable of imparting at least a thousand-fold increase in electrical endurance as measured by an accelerated test procedure. Electrical trees can be initiated in the polyethylene in the presence of the alcohol. However, increased electrical endurance is obtained through inhibition of continued tree growth at that site.A precursor composition for a preferred insulation contains (i) low density polyethylene, (ii) a peroxide crosslinking agent, and (iii) an alcohol of 8 to 12 carbon atoms.

Abstract: A method of producing electrical conductor cable having a polyethylene-based coating, wherein additive material such as a filler is first mixed with a vehicle including an ethylene propylene rubber to provide a homogeneous concentrate, and the concentrate is then blended with polyethylene to constitute a coating composition for application to a cable as by extrusion. The concentrate-polyethylene blending step may be performed by the pumping screw of a cable-coating extruder.

Abstract: Void-free resin impregnated electric motors and generators, the process for producing their void-free resin impregnation and a preferred resin for producing void-free impregnation including a low viscosity, essentially 100 percent solids (i.e. solventless) synthetic resinous material, a thixotropic agent, a surface active agent and/or a diluent are disclosed.

Abstract: The invention relates to electrical insulators having increased resistance to partial discharges and electrical equipment comprising such electrical insulators.These electrical insulators are formed of a macromolecular material in which is incorporated a chelate of general formula: ##STR1## wherein: R.sub.1, R.sub.2 and R.sub.3 each represent hydrogen or a alkyl, aryl, or cycloalkyl group or a heterocyclic group containing a sulphur, oxygen or nitrogen atom, whereby said group or heterocyclic group may be substituted by one or more halogen atoms;X and Y represent oxygen or sulphur;The total number of carbon atoms in the metal chelate is between 5 and 25;M.sup.n+ stands for a metal ion, andN is an integer from 1 to 4, this enolate or thioenolate being present in said insulating material in a sufficient amount for promoting extinction of partial discharges, said amount not exceeding a value which would substantially alter the physical properties of the insulator, such as its volume resistivity.

Abstract: Polyolefin compounds containing nitrile polysiloxane fluid which have improved electrical properties, and electrical conductors insulated therewith.

Abstract: An insulated, multi-conductor electrical cable having a low halogen content and a high degree of resistance to flame and combustion.

Abstract: A crosslink curable ethylene-propylene rubber composition with improved resistance to flame and heat, the cured rubber composition and electrical conductors insulated with the cured rubber composition. The improved rubber composition comprises a combination of ethylene-propylene rubber, chlorosulfonated polyethylene, zinc oxide, hydrated alumina and amorphous silica in particular proportions.

Abstract: A dielectric composition comprising ethylene polymer and effective amounts, as a water treeing inhibitor, of at least one epoxy containing organo silane.

Abstract: Cured insulation compositions are rendered freely strippable from the encased conductors through the use of small amounts of (a) a dialkyl tin diester, (b) N,N'-ethylene bis-stearamide or similar waxy composition, and (c) certain 3-amido-1,2,4-triazoles.

Abstract: A crosslink curable ethylene-propylene rubber composition with improved resistance to heat, the cured rubber composition and electrical conductors insulated with said cured rubber composition. The improved rubber composition comprises a combination of ethylene-propylene rubber, chlorosulfonated polyethylene, zinc oxide, talc and carbon black in particular proportions.

Abstract: Bonding compositions are disclosed as well as bondable articles utilizing such compositions. Such bonding compositions contain a crystalline polyester material and an amorphous polyester material and exhibit thermally stable bonding properties. Such bondable articles include bondable magnet wires comprising a conductor, an insulating base coat thereon and a bonding composition coated thereover containing a crystalline polyester material and an amorphous polyester material with the wires adapted to be shaped as coils and the like and thereafter bonded together with a bond which exhibits bond strength at elevated temperatures.

Abstract: Stabilization of olefin polymers against deterioration in the presence of copper. The stabilization is accomplished by means of a small proportion of a bis-phosphoramidate having the structure ##STR1## where the R's are inert, organic groups.

Abstract: Low density polyethylene with a very small proportion of low molecular weight polyethylene (e.g. such as can be extracted by washing by ethanol) is used as an insulation material for high voltage power cable.