摘要:
The present invention deals with coated pipes having a layer of multimodal polyethylene. The multimodal ethylene copolymer is a copolymer of ethylene with one or more alpha-olefin comonomers having from 4 to 10 carbon atoms and has a weight average molecular weight of from 70000 g/mol to 250000 g/mol, the ratio of the weight average molecular weight to the number average molecular weight, Mw/Mn, of from 15 to 50, a melt index MFR 2 of from 0.05 g/10 min to 5 g/10 min, a melt index MFR 5 of from 0.5 to 10 g/10 min and a density of from 930 kg/m 3 to 955 kg/m 3 . The pipes can be coated with high throughput and good production economy. The coatings have good mechanical properties.
摘要:
The present invention deals with coated pipes having a layer of multimodal polyethylene. The multimodal ethylene copolymer is a copolymer of ethylene with one or more alpha-olefin comonomers having from 4 to 10 carbon atoms and has a weight average molecular weight of from 70000 g/mol to 250000 g/mol and a melt index MFR 2 of from 0.05 g/10 min to 5 g/10 min, a melt index MFR 5 of from 0.5 to 10 g/10 min and a density of from 945 kg/m 3 to 958 kg/m 3 . The coatings have a high stiffness, good properties at elevated temperatures and acceptable stress-cracking properties.
摘要:
The present invention deals with coated pipes having a layer of multimodal polyethylene. The multimodal ethylene copolymer is a copolymer of ethylene with one or more alpha-olefin comonomers having from 4 to 10 carbon atoms and has a weight average molecular weight of from 70000 g/mol to 250000 g/mol, the ratio of the weight average molecular weight to the number average molecular weight, Mw/Mn, of from 15 to 50, a melt index MFR 2 of from 0.05 g/10 min to 5 g/10 min, a melt index MFR 5 of from 0.5 to 10 g/10 min and a density of from 930 kg/m 3 to 955 kg/m 3 . Further, the multimodal ethylene copolymer comprises the multimodal ethylene copolymer comprises from 49 to 59 % based on the weight of the multimodal ethylene copolymer a low molecular weight ethylene homopolymer component, said low molecular weight ethylene homopolymer having a weight average molecular weight of from 5000 g/mol to 70000 g/mol; and from 51 to 41 % based on the weight of the multimodal ethylene copolymer a high molecular weight ethylene copolymer component, said high molecular weight ethylene copolymer having a weight average molecular weight of from 100000 g/mol to 700000 g/mol. The pipes can be coated with high throughput and good production economy. The coatings have good mechanical properties.
摘要:
The present invention relates to a polyethylene composition wherein (i) the composition has an MFR 2 of 0.05 to 100 g/10min, (ii) the environmental stress crack resistance ESCR measured in hours according to ASTM 1693, condition B and E-modulus EM measured according to ISO 527-2:1993 in MPa satisfy the following relation: ESCR ≥ - EM h / MPa + 1150 h .
摘要翻译:本发明涉及一种聚乙烯组合物worin(i)所述组合物具有在12点05分的MFR 2为100克/ 10分钟,(ii)所述耐环境应力开裂ESCR(小时)测得的雅丁到ASTM 1693,条件B和E模量EM 测量gemäß到ISO 527-2:1993兆帕满足以下关系:ESCR‰¥ - EM H / + H兆帕1150次
摘要:
The present invention deals with coated pipes having a layer of multimodal polyethylene. The multimodal ethylene copolymer is a copolymer of ethylene with one or more alpha-olefin comonomers having from 6 to 10 carbon atoms and has a weight average molecular weight of from 70000 g/mol to 250000 g/mol, a melt index MFR 2 of from 0.05 g/10 min to 5 g/10 min, a melt index MFR 5 of from 0.5 to 10 g/10 min and a density of from 930 kg/m 3 to 950 kg/m 3 . It has good mechanical properties in a wide range of service temperature and especially a high resistance against stress cracking.