摘要:
A process is disclosed for producing a multi-modal linear low density polyethylene in at least two staged reactors connected in series, comprising (i) polymerizing in a first slurry phase stage ethylene monomers with a Ziegler-Natta polymerization catalyst system to obtain a first polyethylene fraction component (A); and (ii) polymerizing in a second gas or slurry phase stage ethylene monomers with a Ziegler-Natta polymerization catalyst system to obtain a second polyethylene fraction component (B). The Ziegler-Natta polymerization catalyst system comprises: 1) a solid procatalyst formed by contacting at least: a) a Mg-alcoholate complex of formula (I) b) an aluminum compound of formula (II); and c) a vanadium compound and a titanium compound having a molar ratio (V:Ti) from 10:90 to 90:10; and 2) one or more organometallic cocatalvsts of formula (III). The linear low density polyethylene shows an improved comonomer composition distribution Formulas (I), (II), and (III) are described herein.
摘要:
Multi-stage polymerization process for the production of a multi-modal linear low density polyethylene in at least two staged reactors connected in series comprising at least (i) polymerizing in a first slurry phase stage ethylene monomers and optionally one or more alpha-olefin comonomers, in the presence of a Ziegler-Natta polymerization catalyst system to obtain a first polyethylene fraction component (A) (ii) polymerizing in a second gas or slurry phase stage ethylene monomers and one or more alpha-olefin comonomers, in the presence of a Ziegler-Natta polymerization catalyst system to obtain a second polyethylene fraction component (B), whereby the Ziegler-Natta polymerization catalyst system comprises 1) a solid procatalyst formed by contacting at least: a) a Mg-alcoholate complex of the formula (I): Mg(OR1)2-n(R1)n, wherein each R1 independently represents a C1-C20 hydrocarbyl group and 0≦n
摘要:
Multi-stage polymerization process for the production of a multi-modal linear low density polyethylene in at least two staged reactors connected in series comprising at least (i) polymerizing in a first slurry phase stage ethylene monomers and optionally one or more alpha-olefin comonomers, in the presence of a Ziegler-Natta polymerization catalyst system to obtain a first polyethylene fraction component (A) (ii) polymerizing in a second gas or slurry phase stage ethylene monomers and one or more alpha-olefine comonomers, in the presence of a Ziegler-Natta polymerization catalyst system to obtain a second polyethylene fraction component (B), whereby the Ziegler-Natta polymerization catalyst system comprises: 1) a solid procatalyst formed by contacting at least: a) a Mg-alcoholate complex of the formula (I): Mg(OR1)2-n(R1)n, wherein each R1 independently represents a C1-C20 hydrocarbyl group and 0
摘要:
Ziegler-Natta catalyzed linear low density polyethylene which satisfies the following conditions:a) a density, according to ISO 1183, of from 900 to 925 kg/m3,b) a C4-C10-comonomer content, determined by Fourier transform infrared spectroscopy, of 1 to 16 wt %c) a weight average molecular weight Mw, determined by gel permeation chromatography, of at least 200 000,d) wherein the linear low density polyethylene comprises, by Crystallisation Analysis Fractionation (CRYSTAF) an amorphous fraction soluble at a temperature below 30° C. of at most 10 wt % and a fraction crystallising between 60 to 75° C. of at least 35 wt % ande) by temperature rising elution fractionation (TREF) analysis, at least 70 wt % of a crystallising polymer component having an elution temperature range from 60° C. to 94° C. and less than 10 wt % of a crystallising polymer component having an elution temperature range from 30° C. to 60° C. and,f) by Gel Permeation chromatography coupled with Fourier transform infrared spectroscopy detector (GPC-FTIR), a substantially constant short chain branching profile across the molecular weight distribution (MWD) org) by Gel Permeation chromatography coupled with Fourier transform infrared spectroscopy instruments (GPC-FTIR), a reverse short chain branching profile across the molecular weight distribution (MWD),the linear low density polyethylene being produced in the presence of a special Ziegler-Natta procatalyst and a halogenated aluminium alkyl cocatalyst of the formula (IV) (C1-C4- alkyl)m-Al-X3−m, wherein X is chlorine, bromine, iodine or fluorine and m is 1 or 2.
摘要:
Ziegler-Natta catalyzed linear low density polyethylene which satisfies the following conditions: a) a density, according to ISO 1183, of from 900 to 925 kg/m3, b) a C4-C10-comonomer content, determined by Fourier transform infrared spectroscopy, of 1 to 16 wt % c) a weight average molecular weight Mw, determined by gel permeation chromatography, of at least 200 000, d) wherein the linear low density polyethylene comprises, by Crystallisation Analysis Fractionation (CRYSTAF) an amorphous fraction soluble at a temperature below 30° C. of at most 10 wt % and a fraction crystallising between 60 to 75° C. of at least 35 wt % and e) by temperature rising elution fractionation (TREF) analysis, at least 70 wt % of a crystallising polymer component having an elution temperature range from 60° C. to 94° C. and less than 10 wt % of a crystallising polymer component having an elution temperature range from 30° C. to 60° and, f) by Gel Permeation chromatography using an Fourier transform infrared spectroscopy detector (GPC-FTIR), a substantially constant short chain branching profile across the molecular weight distribution (MWD) or g) by Gel Permeation chromatography coupled with Fourier transform infrared spectroscopy instruments (GPC-FTIR), a revers short chain branching profile across the molecular weight distribution (MWD), the linear low density polyethylene being produced in the presence of a special Ziegler-Natta procatalyst and a halogenated aluminium alkyl cocatalyst of the formula (IV) (C1-C4-alkyl)m-AI-X3-m1, wherein X is chlorine, bromine, iodine or fluorine and m is 1 or 2.
摘要:
Ziegler-Natta catalyst composition capable of producing ethylene/alpha-olefins copolymers, particularly linear low density polyethylene; the composition having an improved stability of its behaviour during polymerization in respect to time. The Ziegler-Natta catalyst composition comprises: 1. Ziegler-Natta catalyst composition for the production of ethylene copolymers comprising A) a procatalyst, which procatalyst comprises a) an Al compound having the formula Al(alkyl)xCl3-x (I), where alkyl is an alkyl group with 1 to 12 and 0≦x≦3, b) a magnesium hydrocarbyloxy compound of formula Mg(OR1)2-n(R2)n (II), wherein each R1 and R2 is independently a C1-20 hydrocarbon residue which may optionally be substituted with halogen and 0≦n
摘要:
A multimodal linear low density polyethylene polymer having a final density of 900 to 940 kg/m3, and containing at least one α-olefin comonomer in addition to ethylene comprising: (A) 30 to 60 wt % of a lower molecular weight component being an ethylene homopolymer or a copolymer of ethylene and at least one α-olefin; and (B) 70 to 40 wt % of a higher molecular weight component being a copolymer of ethylene and at least one α-olefin, said α-olefin being the same or different from any α-olefin used in component (A) but with the proviso that both components (A) and (B) are not polymers of ethylene and butane alone; wherein the multimodal LLDPE has a dart drop of at least 700 g; and wherein components (A) and (B) are obtainable using a Ziegler-Natta catalyst.
摘要:
A multimodal linear low density polyethylene polymer having a final density of 900 to 940 kg/m3, and containing at least one α-olefin comonomer in addition to ethylene comprising: (A) 30 to 60 wt % of a lower molecular weight component being an ethylene homopolymer or a copolymer of ethylene and at least one α-olefin; and (B) 70 to 40 wt % of a higher molecular weight component being a copolymer of ethylene and at least one α-olefin, said α-olefin being the same or different from any α-olefin used in component (A) but with the proviso that both components (A) and (B) are not polymers of ethylene and butane alone; wherein the multimodal LLDPE has a dart drop of at least 700 g; and wherein components (A) and (B) are obtainable using a Ziegler-Natta catalyst.