摘要:
Polymers comprising units derived from ethylene, said polymer having: a) a Melt Index of from 0.05 to 20 g/10 min. as determined by ASTM-1238 Condition E; b) at least 10 per 1000 C-atoms of short chain branches, containing five carbon atoms or less, as determined by C13 NMR, and less than 3.5 mol %, of units derived from a copolymerizable ethylenically unsaturated ester; c) a density of from 0.90 to 0.94 g/cm3, preferably 0.91 to 0.935 g/cm3, especially 0.92 to 0.93 g/cm3 as determined by ASTM D1505; and d) a relaxation time as described herein of at least 10 s. Such polymers can be obtained by free radical polymerization using a chain transfer agent that incorporates into the polymer chain such as an alpha-olefin, preferably propylene, as a chain transfer agent, preferably in a tubular reactor under circumstances to favor LCB formation in a down stream part of the tubular reactor.
摘要翻译:包含衍生自乙烯的单元的聚合物,所述聚合物具有:a)熔体指数为0.05至20g / 10min。 由ASTM-1238条件E确定; b)通过C 13 NMR测定的每1000个碳原子的短链分支中至少有10个,含有5个或更少的碳原子,少于3.5mol%的可共聚烯属不饱和酯衍生的单元; c)0.90至0.94g / cm 3的密度,优选为0.91至0.935g / cm 3,特别是0.92至0.93g / cm 3, SUP>由ASTM D1505确定; 和d)如本文所述的至少10秒的松弛时间。 这样的聚合物可以通过使用引入到聚合物链中的链转移剂(例如α-烯烃,优选丙烯)作为链转移剂的自由基聚合获得,优选在管状反应器中,在有利于LCB形成的条件下 流管部分反应器。
摘要:
This invention relates to blends of linear low density polyethylene copolymers with other linear low density polyethylenes or very low density, low density, medium density, high density, and differentiated polyethylenes. The invention also includes articles produced from the linear low density polyethylene and polyethylene blends described.
摘要:
Heat-shrinkable monolayer and multilayer films are disclosed. The films are formed of a blend of a polyethylene copolymer having a CDBI of at least 70%, a melt index I2.16 of from 0.1 to 15 g/10 min., a density of from 0.910 to 0.940 g/cm3, a melt index ratio I21.6/I2.16 of from 30 to 80, and an Mw/Mn ratio of from 2.5 to 5.5, and a second polymer, such as a low density polyethylene (LDPE). The heat-shrinkable films have a combination of improved optical and mechanical properties.
摘要翻译:公开了热收缩单层和多层膜。 该膜由具有至少70%的CDBI,0.1至15g / 10min的熔体指数I <2.16 sub>,密度为0.910至0.940的聚乙烯共聚物的共混物形成 g / cm 3,熔体指数比I 21.6 / I 2.16 sub> 30至80,Mw / Mn比为2.5 至5.5,以及第二聚合物,例如低密度聚乙烯(LDPE)。 热收缩膜具有改进的光学和机械性能的组合。
摘要:
At least two techniques can be used separately or together to achieve higher clarity in multilayer blown coextruded films. In a first technique, the core layer is extruded at a higher temperature than the skin layer or layers. In the second technique, the core layer has a higher density than the skin layer or layers. Combinations of these techniques are also contemplated. Either one or both techniques may be used to a sufficient degree to improve clarity (generally lower haze).
摘要:
The invention relates to a blown film coextrusion process. The process involves extruding core contact layers through a die exit at a specified speed and cooling, orienting and crystallizing the multi-layer film formed at a specified deformation rate to form a the frost line is a specified distance from the die exit by withdrawing film at a take up speed. The core and core contact layers are of a film forming polymer composition comprising at least 90 wt % of ethylene based polymer. The ethylene based polymer of the core layer has an average density of ethylene based polymers equal to or higher than that of ethylene based polymer of the core contact layers. The invention specifically concerns the feature that the core layer composition contains a portion of and the composition of the core contact layers contains a portion of a linear polyethylene so as to make the core layer more resistant to deformation than the skin layers.
摘要:
The invention relates to a polymer comprising units derived from ethylene having: a) a Melt Index of from 0.05 to 20 g/10 min; b) at least 10 per 1000 C-atoms of short chain branches, containing five carbon atoms or less, and less than 3.5 mol %, of units derived from a copolymerizable ethylenically unsaturated ester, c) a density of from 0.90 to 0.94 g/cm3, preferably 0.91 to 0.935 g/cm3, especially 0.92 to 0.93 g/cm3, and d) a relaxation time as described herein of at least 10 s. The polymer may be used for stretch hood film, preferably as a blown film coextruded tube comprising: a) a core of the above polymer; and b) a skin layer, on each side of the core which may be of the same or different composition, comprising at least 60 wt % of an LLDPE having density of 0.91 to 0.94 g/cm3.
摘要翻译:本发明涉及包含衍生自乙烯的单元的聚合物,其具有:a)熔体指数为0.05至20g / 10min; b)每1000个碳原子的短链分支中至少有10个,含有5个或更少的碳原子,少于3.5摩尔%的可共聚烯属不饱和酯的单体,c)密度为0.90-0.94克/ cm 3,优选为0.91〜0.935g / cm 3,特别是0.92〜0.93g / cm 3,d)如本文所述的弛豫时间为至少10s。 聚合物可用于拉伸罩膜,优选用作吹塑膜共挤出管,其包含:a)上述聚合物的芯; 和b)在芯的每侧可以具有相同或不同组成的皮肤层,其包含至少60重量%的密度为0.91至0.94g / cm 3的LLDPE。
摘要:
Stretch films are disclosed, the films having at least one layer formed of or including a polyethylene copolymer and having a natural draw ratio of at least 250%, a tensile stress at the natural draw ratio of at least 22 MPa, and a tensile stress at second yield of at least 12 MPa. In some embodiments, the polyethylene copolymer can have a CDBI of at least 70%, a melt index I2.16 of from 0.1 to 15 g/10 min., a density of from 0.910 to 0.940 g/cm3, a melt index ratio I21.6/I2.16 of from 30 to 80, and an Mw/Mn ratio of from 2.5 to 5.5. The stretch films are particularly useful in bundling and packaging applications.
摘要:
The invention relates to a blown film coextrusion process. The process involves extruding core contact layers through a die exit at a specified speed and cooling, orienting and crystallizing the multi-layer film formed at a specified deformation rate to form a the frost line is a specified distance from the die exit by withdrawing film at a take up speed. The core and core contact layers are of a film forming polymer composition comprising at least 90 wt % of ethylene based polymer. The ethylene based polymer of the core layer has an average density of ethylene based polymers equal to or higher than that of ethylene based polymer of the core contact layers. The invention specifically concerns the feature that the core layer composition contains a portion of and the composition of the core contact layers contains a portion of a linear polyethylene so as to make the core layer more resistant to deformation than the skin layers.