Scg Chemicals Company Limited

Thai Polyethylene Co., Ltd.

Mitsui Chemicals, Inc.

Warachad Klomkamol

Watcharee Cheevasrirungruang

Natthaporn Suchao-In

Saranya Traisilanun

Patcharin Samphawamontri

Arunsri Mattayan

Shinichi Kojoh

Eiji Shiba

Kenji Iwamasa

Piyawan Tiyapiboonchaiya

Takashi Fukawa

Thipphaya Pathaweeisariyakul

Chatdao Suk-Em

Yasunori Kaneko

Boonyakeat Thitisak

Kanyanut Narkchamnan

Hathaichanok Boonyang

Nattapom Suchao-In

Thippaya Pathaweeisariyakul

The present invention relates to a process for producing a multimodal polyethylene composition in the reactor system according to the invention, comprising; (a) polymerizing ethylene in an inert hydrocarbon medium in the first reactor in the presence of a catalyst system, selected from Ziegler-Natta catalyst or metallocene, and hydrogen in an amount of 0.1-95% by mol with respect to the total gas present in the vapor phase in the first reactor to obtain a low molecular weight polyethylene or a medium molecular weight polyethylene; (b) removing in the hydrogen removal unit 98.0 to 99.8% by weight of the hydrogen comprised in a slurry mixture obtained from the first reactor at a pressure in the range of 103-145 kPa (abs) and transferring the obtained residual mixture to the second reactor; (c) polymerizing ethylene and optionally Cto Cα-olefin comonomer in the second reactor in the presence of a catalyst system, selected from Ziegler-Natta catalyst or metallocene, and in the presence of hydrogen in an amount obtained in step (b) to obtain a first high molecular weight polyethylene or a first ultra high molecular weight polyethylene in the form of a homopolymer or a copolymer and transferring a resultant mixture to the third reactor; and (d) polymerizing ethylene, and optionally α-olefin comonomer in the third reactor in the presence of a catalyst system, selected from Ziegler-Natta catalyst or metallocene, and hydrogen, wherein the amount of hydrogen in the third reactor is in a range of 1-70% by mol, preferably 1-60% by mol with respect to the total gas present in the vapor phase in the third reactor or optionally substantial absence of hydrogen to obtain a second high molecular weight polyethylene or a second ultra high molecular weight polyethylene homopolymer or copolymer; and a multimodal polyethylene composition obtainable this way.

Reactor system for multimodal polyethylene polymerization

The present invention relates to a multimodal polyethylene composition comprising: (A) 40 to 65 parts by weight, preferably 43 to 52 parts by weight, most preferred 44 to 50 parts by' weight, of the low molecular weight polyethylene having a weight average molecular weight (Mw) of 20,000 to 90,000 g/mol, wherein the low molecular weight polyethylene has a MI2 of 500 to 1,000 g/10 min according to ASTM D 1238; (B) 5 to 17 parts by weight, preferably 10 to 17 parts by weight, most preferred 10 to 15 parts by weight, of the first high molecular weight polyethylene having a weight average molecular weight (Mw) of more than 150,000 to 1,000,000 g/mol or the first ultra high molecular weight polyethylene having a weight average molecular weight (Mw) of more than 1,000,000 to 5,000,000 g/mol; and (C) 30 to 50 parts by weight, preferably 37 to 47 party by weight, most preferably 39 to 45 parts by weight, of the second high molecular weight polyethylene having a weight average molecular weight (Mw) of more than 150,000 to 1,000,000 g/mol or the second ultra high molecular weight polyethylene having a weight average molecular weight (Mw) of more than 1,000,000 to 5,000,000 g/mol, wherein the density of the first high molecular weight polyethylene or the first ultra high molecular weight polyethylene and the second high molecular weight polyethylene or the second ultra high molecular weight polyethylene is in the same range and both densities are in the range from 0.910 to 0.940 g/cm3; and the molecular weight distribution of the multimodal polyethylene composition is from 18 to 30, preferably 20 to 28, measured by gel permeation chromatography, film comprising the multimodal polyethylene composition and the use thereof.

Multimodal polyethylene film

The present invention relates to a reactor system for a multimodal polyethylene polymerization process, comprising; (a) a first reactor; (b) a hydrogen removal unit arranged between the first reactor and a second reactor comprising at least one vessel connected with a depressurization equipment, preferably selected from vacuum pump, compressor, blower, ejector or a combination thereof, the depressurization equipment allowing to adjust an operating pressure to a pressure in a range of 100-200 kPa (abs); (c) the second reactor; and (d) a third reactor and the use thereof as a container.

Multimodal polyethylene container

The present invention relates to a reactor system for a multimodal polyethylene polymerization process, comprising: (a) first reactor; (b) a hydrogen removal unit arranged between the first reactor and a second reactor comprising at least one vessel connected with a depressurization equipment, preferably selected, from vacuum pump, compressor, blower, ejector or a combination thereof, the depressurization equipment allowing to adjust an operating pressure to a pressure in a range of 100-200 kPa (abs); (c) the second reactor; and (d) a third reactor and use thereof as a pipe.

Multimodal polyethylene pipe

The present invention relates to a reactor system for a multimodal polyethylene composition comprising: (a) first reactor; (b) hydrogen removal unit arranged between the first reactor and a second reactor comprising at least one vessel connected with a depressurization equipment, preferably selected from vacuum pump, compressor, blower, ejector or a combination thereof, the depressurization equipment allowing to adjust an operating pressure to a pressure in a range of 100-200 kPa (abs); (c) the second reactor; and (d) a third reactor and use thereof as a pipe.

The present invention relates to a multimodal polyethylene composition comprising: (A) 40 to 65 parts by weight, preferably 43 to 52 parts by weight, most preferred 44 to 50 parts by weight, of the low molecular weight polyethylene, the low molecular weight polyethylene having a weight average molecular weight (Mw) of 20,000 to 90,000 g/mol and having a MFRa from 500 to 1.000 g/10 min according to ASTM D 1238; (B) 8 to 20 parts by weight, preferably 10 to 18 parts by weight, most preferred 10 to 15 parts by weight, of the first high molecular weight polyethylene having a weight average molecular weight (Mw) of more than 150,000 to 1,000,000 g/mol or the first ultra high molecular weight polyethylene having a weight average molecular weight (Mw) of more than 1,000,000 to 5,000,000 g/mol; and (C) 30 to 50 parts by weight, preferably 37 to 47 parts by weight, most preferred 39 to 45 parts by weight, of the second high molecular weight polyethylene having a weight average molecular weight (Mw) of more than 150,000 to 1,000,000 g/mol or the second ultra high molecular weight polyethylene having a weight average molecular weight (Mw) of more than 1,000,000 to 5,000,000 g/mol, wherein the density of the first high molecular weight polyethylene or the first ultra high molecular weight polyethylene and the second high molecular weight polyethylene or the second ultra high molecular weight polyethylene are in the range from 0.920 to 0.950 g/cm3, and wherein the molecular weight distribution of the multimodal polyethylene composition is from 20 to 28, preferably from 24 to 28, measured by gel permeation chromatography, and a film comprising the multimodal polyethylene composition and the use thereof.

Multimodal polyethylene composition and a film comprising the same

The present invention relates to a multimodal polyethylene composition comprising: (A) 35 to 65 parts by weight, preferably 45 to 65 parts by weight, most preferred 50 to 60 parts by weight, of the low molecular weight polyethylene having a weight average molecular weight (Mw) of 20,000 to 90,000 g/mol; (B) 5 to 40 parts by weight, preferably 5 to 30 parts by weight, most preferred 5 to 20 parts by weight, of the first high molecular weight polyethylene having a weight average molecular weight (Mw) of more than 150,000 to 1,000,000 g/mol or the first ultra high molecular weight polyethylene having a weight average molecular weight (Mw) of more than 1,000,000 to 5,000,000 g/mol; and (C) 20 to 60 parts by weight, preferably 25 to 60 parts by weight, most preferred 35 to 55 parts by weight, of the second high molecular weight polyethylene having a weight average molecular weight (Mw) of more than 150,000 to 1,000,000 g/mol or the second ultra high molecular weight polyethylene having a weight average molecular weight (Mw) of more than 1,000,000 to 5,000,000 g/mol, wherein the molecular weight distribution of the multimodal polyethylene composition is from 10 to 25, preferably 10 to 20, determined by Gel Permeation Chromatography; the isothermal crystallization half-time of the multimodal polyethylene composition at a temperature of 123&#xb0; C. is 7 min or less, preferably 6 min or less, preferably 2-6 min, according to Differential Scanning Calorimetry; and a spiral flow length at a temperature of 220&#xb0; C. is at least 200 mm, preferably 250-400 mm and a screw cap comprising the same.

Multimodal polyethylene screw cap

The present invention relates to a bimodal polyethylene composition comprising a low molecular weight polyethylene homopolymer fraction and high molecular weight polyethylene copolymer fraction having a Cto C&#x3b1;-olefin comonomer content of 0.25 to 3% mol with respect to the total monomer comprised in the high molecular weight polyethylene comonomer fraction, wherein the content of the low molecular weight polyethylene is from 50 to 60 wt % with respect to the total weight of the bimodal polyethylene composition; and the bimodal polyethylene composition has a soluble fraction according to Temperature Rising Elution Fractionation in 1,2,4-trichlorobenzene with 300 ppm of butylated hydroxytoluene at 150&#xb0; C. of less than 6 wt %; and a pipe comprising the same.

Bimodal polyethylene composition and pipe comprising the same

The pipe articles with excellent stress crack resistance can be achieved by providing ethylene copolymer composition comprises ethylene and a C6-C10 &#x3b1;-olefin comonomer; the ethylene copolymer having a total density of 0.945-0.980 g/cmand a MFRof 0.10-0.50 g/10 min; and the ethylene copolymer having a comonomer content of 1-5% wt. The ethylene copolymer has M/Min the range of not less than 14.0; gpcBR in the range of from 0.20 to 0.80; and strain hardening modulus &#x3c;Gp&#x3e; in the range of not less than 53.4.

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Bangkok, Thailand

Warachad Klomkamol