摘要:
Certain embodiments of the present technology provide a cable comprising a conductor and a cable layer. The cable layer comprises a polypropylene material. The cable layer and/or the polypropylene material comprise a crystalline fraction crystallizing in the temperature range of 200 to 105° C. determined by stepwise isothermal segregation technique. The crystalline fraction comprises a part, wherein, during subsequent melting at a melting rate of 10° C./min, the part melts at or below 130° C. and the part represents at least 20 percent by weight of the crystalline fraction. In certain embodiments, the part melts at or below the temperature T=Tm−3° C., wherein Tm is the melting temperature of the cable layer and/or the polypropylene material, and the part represents at least 45 percent by weight of the crystalline fraction. Certain embodiments provide methods and processes for manufacturing the cable described above and herein.
摘要:
Certain embodiments of the present technology provide a cable comprising a conductor and a cable layer. The cable layer comprises a polypropylene material. The cable layer and/or the polypropylene material comprise a crystalline fraction crystallizing in the temperature range of 200 to 105° C. determined by stepwise isothermal segregation technique. The crystalline fraction comprises a part, wherein, during subsequent melting at a melting rate of 10° C./min, the part melts at or below 130° C. and the part represents at least 20 percent by weight of the crystalline fraction. In certain embodiments, the part melts at or below the temperature T=Tm−3° C., wherein Tm is the melting temperature of the cable layer and/or the polypropylene material, and the part represents at least 45 percent by weight of the crystalline fraction. Certain embodiments provide methods and processes for manufacturing the cable described above and herein.
摘要:
Certain embodiments of the present technology provide a cable layer comprising a polypropylene material, where the cable layer and/or the polypropylene material comprise a crystalline fraction that crystallizes in a temperature range of 200 to 105° C., determined by stepwise isothermal segregation technique. The crystalline fraction comprises a part which during subsequent melting of the crystalline fraction at a melting rate of 10° C./min, the part melts at or below 140° C. and the part represents at least 10 percent by weight of the crystalline fraction. Certain embodiments also provide a process for the preparation of a cable layer, comprising providing the polypropylene material described herein and forming the polypropylene material into a cable layer.
摘要:
The present invention relates to a cable comprising a conductor surrounded by one or more layers, wherein at least one layer comprises a polymer composition comprising a multimodal copolymer of ethylene with one or more comonomers, to a process for producing the cable and to a polymer composition suitable as a cable layer material.
摘要:
The present invention relates to a semiconductive polymer composition comprising an olefin homo- or copolymer wherein the composition has a direct current volume resistivity of less than 1000 Ohm·cm at 90° C., an elongation at break which after aging for 240 hours at 135° C. does not change by more than 25%, and a total number of structures of 20 or less in the SIED test. Furthermore, the present invention relates to an electric power cable comprising a conductor, a semiconducting layer and, adjacent to the semiconducting layer, an insulation layer, wherein the semiconducting layer is formed by said semiconductive polymer composition and to the use of said semiconducting polymer composition for the production of a semiconductive layer of an electric power cable.
摘要:
The use in the manufacture of a polyethylene article of a polyethylene composition comprising 20 to 50% wt of a copolymer of ethylene and a C3-20 alpha olefin comonomer and 50 to 80% wt. Of a lower weight average molecular weight ethylene polymer, the polyethylenes of the composition together having a density of 935 to 965 kg/m3, weight average molecular weight of 60000 to 300000 g/mol, an MFR2.16 at 190° C. of 0.1 to 10 g/10 min., and a molecular weight distribution (MWD) of from 2.5 to 20, the copolymer having a comonomer content of from 0.006 to 9 mol % and a degree of branching of 0.03 to 45 branches per 1000 carbons, and the ethylene polymer having a density of 939 to 975 kg/m3 and a weight average molecular weight of 20000 to 200000 g/mol.
摘要:
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.
摘要:
The present invention relates to a power or communications cable comprising an outer sheath layer made of a polyethylene composition comprising a base resin which comprises (A) a first ethylene homo- or copolymer fraction, and (B) a second ethylene homo- or copolymer fraction, wherein fraction (A) has a lower molecular weight than fraction (B), and the base resin has a molecular weight distribution Mw/Mn of more than 14.
摘要:
A multimodal copolymer of ethylene comprising at least (i) a lower molecular weight fraction of a copolymer of ethylene and at least one alpha-olefin comonomer and (ii) a higher molecular weight fraction of a copolymer of ethylene and at least one alpha-olefin comonomer, wherein said copolymer has a density below 920 kg/m3.
摘要翻译:一种乙烯的多峰共聚物,其至少包含(i)乙烯与至少一种α-烯烃共聚单体的共聚物的较低分子量馏分和(ii)乙烯与至少一种α-烯烃的共聚物的较高分子量馏分 共聚单体,其中所述共聚物的密度低于920kg / m 3。
摘要:
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. The copolymer is preferably obtained by high pressure radical polymerisation in a tubular reactor.