Abstract: An insulating composition for an electric power cable, and an electric power cable that includes a conductor surrounded by an inner semiconducting layer, an insulating layer, and an outer semiconducting layer, where the insulating layer consists of said insulating composition. The insulating composition is characterized in that the ethylene polymer is a multimodal ethylene copolymer obtained by coordination catalyzed polymerization of ethylene and at least one other alpha-olefin in at least one stage, said multimodal ethylene copolymer having a density of 0.890-0.940 g/cm3, a MFR2 of 0.1-10 g/10 min, a MWD of 3.5-8, a melting temperature of at most 125° C., and a comonomer distribution as measured by TREF, such that the fraction of copolymer eluted at a temperature higher than 90° C. does not exceed 10% by weight, and the multimodal ethylene copolymer includes an ethylene copolymer fraction selected from (a) a low molecular weight ethylene copolymer having a density of 0.900-0.

Abstract: A semiconducting composition for electric cables, an electric cable incorporating the composition, and a method of producing a cross-linked semiconducting layer of an electric cable are disclosed. The semiconducting composition comprises, based on the total weight of the composition, (a) 50-90% by weight of an ethylene copolymer, (b) carbon black in an amount at least sufficient to make the composition semiconducting, (c) 0-8% by weight of a peroxide cross-linking agent, (d) 0-8% by weight of conventional additives, characterised in that the ethylene copolymer (a) is a heterogeneous ethylene-alkyl(meth)acrylate copolymer, which besides ethylene moieties comprises 2-10 mole % of an alkyl(meth)acrylate comonomer moiety, chosen among methyl(meth)acrylate, ethyl(meth)acrylate, (iso-)propyl(meth)acrylate and butyl(meth)acrylate, and the melting point of which is at least 95° C. and is higher than (108.5−1.7×(mole % of alkyl (meth)acrylate comonomer)) degree centigrade.

Abstract: A cable comprising an electrical conductor with insulating and protecting layers surrounding the conductor is described. The cable is characterised in that at least one layer selected from said insulating and protecting layers consists of a crosslinked ethylene-alkyl (meth)acrylate-unsaturated silane terpolymer composition wherein the alkyl (meth)acrylate comonomer comprises more than 5 mole % and the terpolymer composition has a tensile modulus, determined according to ISO 527-2 (1 mm/min) of less than 100 MPa. Preferably, the crosslinked ethylene-alkyl (meth)acrylate polymer is a moisture curable ethylene-alkyl (meth)acrylate-vinyl trialkoxysilane terpolymer, wherein the trialkoxysilan termonomer comprises 0.2-5% by weight of the polymer composition. The polymer composition may include from 0 up to 50% by weight of a plasticiser, up to 60% by weight of a filler, and up to 10% by weight of an additive.

Abstract: The present invention relates to a stabilizing agent for polymers or copolymers which is a copolymer of ethylene or propylene (A) and a vinyl compound (B) having the formula: 1

Abstract: A composition for an insulating layer of an electric cable wherein the composition contains an ethylene plastic as the base resin and further contains up to about 5% by weight of additives including antioxidant, and peroxide cross-linking agent. The composition is characterised in that the antioxidant additive includes a compound of the formula (V): R1(—(C+O)O—)k(CH2)1—S—(CH2)m(—OO(C═O)—)nR2 where R1 and R2, which are the same of different, are C7-C23 alkyl, C7-C23 alkenyl, R3—Ar—, Ar—R3—, or AR—, where R3 is C8-C24 alkyl and Ar is c6-c14 aryl; k and n, which are the same of different, are 0 or 1, l and m, which are the same or different, are integers ≧0; with the proviso that the compound is free from phenolic groups; and that the compositions is free from compounds having the formula (VI): R—O—(C═O)—CH2CH2SCH2CH2—(C═O)—O—R where R is a C8-C20 alkyl group.

Abstract: A semiconducting composition for the inner semiconducting layer of an electric cable, an electric cable incorporating the composition, and a method of producing a cross-linked inner semiconducting layer of an electric cable are disclosed. The semiconducting composition comprises, based on the total weight of the composition, (a) 30-90% by weight of an ethylene copolymer, (b) carbon black in an amount at least sufficient to make the composition semiconducting, (c) 0-8% by weight of a peroxide cross-linking agent, (d) 0-8% by weight of conventional additives, characterized in that said ethylene copolymer (a) is an ethylene-methyl (meth)acrylate copolymer, preferably comprising 5-25% by weight of methyl(meth)acrylate, based on the weight of the copolymer.

Abstract: A semiconducting composition for electric cables, an electric cable incorporating the composition, and a method of producing a cross-linked semiconducting layer of an electric cable are disclosed.

Abstract: An insulated DC-cable and method for production of an insulated DC-cable with an insulating system comprising an extruded cross-linked polyethylene based insulation disposed around the conductor. The extruded polyethylene based compound comprises additives such as cross-linking agent, scorch retarding agent and antioxidant. The scorch retarding agent comprises a compound (D), 2,4-diphenyl-4-methyl-pentene-1 and the antioxidant comprises a compound (C), a diester of 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionicacid and thiodiglycol. The compounded polyethylene based resin composition is extruded and cross-linked at a temperature and for a period of time sufficient enough to cross link the insulation. The temperature and the period of time upon extrusion and cross-linking are limited so as to substantially suppress or essentially avoid undesired polar by-products being formed in the cross-linked composition.

Abstract: A process for the reduction of reactor fouling at radical initiated high pressure polymerisation of ethylene (co)polymers is described. The process is characterised in that an adhesion reducing silicon containing compound is added to the polymerisation reactor, preferably in an amount of 0.001-3% by weight, based on the amount of polymer produced. Preferably the silicon containing compound is hexadecyl trimethoxy silane.

Abstract: A composition for electric cables is described. The composition comprises an ethylene copolymer which includes a (poly)alkylene glycol mono(meth)acrylate of formula (I) wherein R.sub.1 =H or CH.sub.3 ; R.sub.2 =H or CH.sub.3 ; n=1-20. The composition may be used as an insulating layer or a semiconducting layer of an electric cable.

Abstract: A crosslinkable polymer composition contains a crosslinkable polymer with hydrolysable silane groups and at least one silanol condensation catalyst. The polymer composition is distinguished by the silanol condensation catalyst being a compound of the formula ArSO.sub.3 H (I) or a precursor thereof, Ar being a substituted benzene or naphthalene ring, the substituent or substituents containing 4-20 carbon atoms, preferably 10-18 carbon atoms. The precursor may be an anhydride of the sulphonic acid of formula (I), or a sulphonic acid of formula (I) provided with a hydrolysable protective group, eg. an acetyl group. Specific examples of compounds of formula (I) are dodecyl benzene sulphonic acid and tetrapropyl benzene sulphonic acid.

Abstract: The invention concerns an unsaturated ethylene copolymer, a method for producing the ethylene copolymer, and the use of the ethylene copolymer in compositions for producing cross-linked structures, such as material for electric cables. In the method, ethylene and at least one monomer which is copolymerizable with ethylene and includes a polyunsaturated comonomer having a chain of at least 8 carbon atoms and at least 2 non-conjugated double bonds, of which at least one is terminal, are polymerized at a pressure of about 100-300 MPa and a temperature of about 80.degree.-300.degree. C. under the action of a radical initiator. The polyunsaturated comonomer preferably is an .alpha.,.omega.-alkadiene having 8-16 carbon atoms, most preferred 1,9-decadiene. Apart from the polyunsaturated comonomer, polymerization may also involve another vinyl-unsaturated monomer, preferably containing at least one functional group selected from hydroxyl groups, alkoxy groups, carbonyl groups, carboxyl groups and ester groups.

Abstract: The invention relates to a process for the preparation of a solid procatalyst composition of a catalyst system for the polymerization of olefins wherein a magnesium halide such as magnesium chloride is dissolved and/or suspended into an alkyl ester of a monocarboxylic acid such as ethyl acetate, impregnated to a carrier, treated with an organometallic compound or a silicon compound and thereafter with a transition metal compound. The invention also relates to a procatalyst composition and its use together with a cocatalyst for the polymerization of olefins. The activity has been enhanced according to the invention by the use of a carrier containing hydroxyl groups, which carrier is kept at a temperature of at most about 200.degree. C. prior to the impregnation so that the hydroxyl groups are retained in the carrier to an essential extent until the impregnation step. The carrier is preferably silica which is treated thermally at 100.degree.-200.degree. C.

Abstract: A process for eliminating in plastic materials odor/taste-producing substances is described, the plastic material especially having the shape of water pipes, plastic containers or plastic film/sheeting for packing foodstuffs and pharmaceutical preparations, or interior fittings of plastic. In the process, there is added, during processing in the molten state, less than 0.5 wt.-%, preferably 0.05-0.3 wt.-%, of a substantially hydrophobic aluminum silicate molecular sieve having a pore diameter of at least 5.5 .ANG., an Si/Al molar ratio in the crystal lattice of at least 35, preferably 200-500, and a sorption capacity for water at 25.degree. C. and 4.6 torr of less than 10 wt.-%, to the plastic material which subsequently is formed. The molecular sieve preferably has an average particle size not exceeding about 5 .mu.m. The plastic material is a polyolefin plastic and is preferably selected among ethylene plastics and propylene plastics.

Abstract: The invention relates to a method for the preparation of a solid procatalyst composition for a catalyst system intended for the polymerization of olefins, wherein a magnesium halide, such as magnesium chloride, is dissolved and/or slurried in a mono-carboxylic acid alkyl ester, such as ethyl acetate, is impregnated into a support material, dried, treated with an organometallic compound or a silicon compound and thereafter with a transition metal compound. The invention also relates to such a procatalyst composition and its use together with a cocatalyst for the polymerization of olefins. According to the invention it has been possible to increase the activity of the catalyst composition by using a silanated support material, such as silanated silica, which is then treated with an organometallic or silicon compound before treatment with a transition metal compound. The silanated silica is preferably a silicon dioxide which has been heat-treated at 1000.degree.-200.degree.

Abstract: The invention relates to a new bis(trialkylsilyl) chromate of the formula ##STR1## where n is approximately 1-2. Such a compound can be prepared by causing a corresponding silyl halide to react with silver chromate. The product is especially suitable for the polymerization and copolymerization of ethylene, the formed polymer having a high molar mass and a wide molar mass distribution.