Ultrahigh-molecular ethylene polymer

Abstract

An ultrahigh-molecular ethylene polymer which is either an ethylene homopolymer (A) or an ethylene copolymer (B) obtained by copolymerizing a) 99.9 to 75.0 wt.% ethylene with b) 0.1 to 25.0 wt.% at least one olefin comonomer selected from the group consisting of C3-20 alpha-olefins, C3-20 cycloolefins, compounds represented by the formula CH2=CHR (wherein R is C6-20 aryl), and C4-20 linear, branched, or cyclic dienes, and which has i) a viscosity-average molecular weight of 1,000,000 or higher, ii) a molecular-weight distribution (Mw / Mn) of 3 or higher, and iii) a titanium content of 3 ppm or lower and a chlorine content of 5 ppm or lower.

Description

technical field

[0001] The present invention relates to an ultrahigh molecular weight ethylene polymer (ethylene homopolymer or ethylene copolymer) having an ultrahigh molecular weight of 1,000,000 or more, a molecular weight distribution greater than 3, and a small residual amount of Ti and Cl in the polymer, and the production of the ultrahigh molecular weight ethylene polymer (ethylene homopolymer or ethylene copolymer). Process for high molecular weight ethylene polymers. Background technique

[0002] Ultra-high molecular weight polyolefins, especially ultra-high molecular weight polyethylene, have excellent impact strength, abrasion resistance, slip properties, and chemical resistance compared with widely used polyethylene, which can be used for sliding parts and are therefore listed as An engineering plastic. Furthermore, after uniform mixing with plasticizers such as paraffin oil, they are extruded into sheets, films or fibers, or stretched in some cases and then use...

Examples

Embodiment 1-9 and comparative example 1-4

[0253] The present invention is described in detail below with reference to Examples and Comparative Examples. The present invention is by no means limited by these Examples. The measurement methods used in Examples and Comparative Examples are as follows.

[0254] [Measurement of Mw / Mn]

[0255] Using a 150-CA LC / GPC device (Waters Corporation), ShodexAT-807S (purchased from Showa Denko K.K.) and TSK-gel GMH-H16 (purchased from Tosoh Corporation) were used as columns in series, and a three-phase column containing 10 ppm IRGANOX1010 (Ciba Specialty Chemicals) was used. Chlorobenzene was used as solvent and measurements were carried out at 140 °C. A commercially available monodisperse polystyrene was used as a reference material to generate a calibration curve.

[0256] [Measurement of viscosity average molecular weight]

[0257] 2 mg of the polymer was added to 20 ml of decalin, and stirred at 150° C. for 2 hours to dissolve the polymer. Use the Ubbelohde viscometer to meas...

Embodiment 1

[0279] (preparation of compound (D) with hydrogenation ability)

[0280] A 3% by weight hexane suspension containing 30 mmol titanocene dichloride (available from Wako Pure Chemical Industries, Ltd.) and 60 mmol 1M trimethylaluminum hexane solution was stirred at room temperature for 100 hours to prepare Tebbe's reagent.

[0281] (Polymerizing ethylene: Preparation of ethylene homopolymer (A))

[0282] Isobutane, ethylene, hydrogen, metallocene catalyst, and Tebbe's reagent were continuously fed into a vessel-type polymerization reactor equipped with a stirrer to produce polyethylene (ethylene homopolymer) at a productivity of 10 kg / Hr. Hydrogen purified to 99.99 mol % or higher by contact with molecular sieves is used. Using [(N-tert-butylamino) (tetramethyl-η 5 -cyclopentadienyl)dimethylsilyl]titanium-1,3-pentadiene, bis(hydrogenated tallow alkyl)methylammonium-tris(pentafluorophenyl)(4-hydroxyphenyl)boron A catalyst obtained by loading a mixture of triethylaluminum salt ...

Embodiment 2

[0284] Polymerization was performed in the same manner as in Example 1, except that Tebbe's reagent was fed at a rate of 0.013 mmol / hour. In this case, no bulk polymer was produced, nor was the slurry discharge pipe blocked, and stable continuous operation was achieved. The resulting polyethylene had an average molecular weight of 2,100,000 as determined by intrinsic viscosity (135° C.) in decalin, a density of 0.9300 g / cc and a crystallinity of 52%. The results of these and other measurements for this example are shown in Table 1.

technical field

[0001] The present invention relates to an ultrahigh molecular weight ethylene polymer (ethylene homopolymer or ethylene copolymer) having an ultrahigh molecular weight of 1,000,000 or more, a molecular weight distribution greater than 3, and a small residual amount of Ti and Cl in the polymer, and the production of the ultrahigh molecular weight ethylene polymer (ethylene homopolymer or ethylene copolymer). Process for high molecular weight ethylene polymers. Background technique

[0002] Ultra-high molecular weight polyolefins, especially ultra-high molecular weight polyethylene, have excellent impact strength, abrasion resistance, slip properties, and chemical resistance compared with widely used polyethylene, which can be used for sliding parts and are therefore listed as An engineering plastic. Furthermore, after uniform mixing with plasticizers such as paraffin oil, they are extruded into sheets, films or fibers, or stretched in some cases and then use...

Examples

Embodiment 1-9 and comparative example 1-4

[0253] The present invention is described in detail below with reference to Examples and Comparative Examples. The present invention is by no means limited by these Examples. The measurement methods used in Examples and Comparative Examples are as follows.

[0254] [Measurement of Mw / Mn]

[0255] Using a 150-CA LC / GPC device (Waters Corporation), ShodexAT-807S (purchased from Showa Denko K.K.) and TSK-gel GMH-H16 (purchased from Tosoh Corporation) were used as columns in series, and a three-phase column containing 10 ppm IRGANOX1010 (Ciba Specialty Chemicals) was used. Chlorobenzene was used as solvent and measurements were carried out at 140 °C. A commercially available monodisperse polystyrene was used as a reference material to generate a calibration curve.

[0256] [Measurement of viscosity average molecular weight]

[0257] 2 mg of the polymer was added to 20 ml of decalin, and stirred at 150° C. for 2 hours to dissolve the polymer. Use the Ubbelohde viscometer to meas...

Embodiment 1

[0279] (preparation of compound (D) with hydrogenation ability)

[0280] A 3% by weight hexane suspension containing 30 mmol titanocene dichloride (available from Wako Pure Chemical Industries, Ltd.) and 60 mmol 1M trimethylaluminum hexane solution was stirred at room temperature for 100 hours to prepare Tebbe's reagent.

[0281] (Polymerizing ethylene: Preparation of ethylene homopolymer (A))

[0282] Isobutane, ethylene, hydrogen, metallocene catalyst, and Tebbe's reagent were continuously fed into a vessel-type polymerization reactor equipped with a stirrer to produce polyethylene (ethylene homopolymer) at a productivity of 10 kg / Hr. Hydrogen purified to 99.99 mol % or higher by contact with molecular sieves is used. Using [(N-tert-butylamino) (tetramethyl-η 5 -cyclopentadienyl)dimethylsilyl]titanium-1,3-pentadiene, bis(hydrogenated tallow alkyl)methylammonium-tris(pentafluorophenyl)(4-hydroxyphenyl)boron A catalyst obtained by loading a mixture of triethylaluminum salt ...

Embodiment 2

[0284] Polymerization was performed in the same manner as in Example 1, except that Tebbe's reagent was fed at a rate of 0.013 mmol / hour. In this case, no bulk polymer was produced, nor was the slurry discharge pipe blocked, and stable continuous operation was achieved. The resulting polyethylene had an average molecular weight of 2,100,000 as determined by intrinsic viscosity (135° C.) in decalin, a density of 0.9300 g / cc and a crystallinity of 52%. The results of these and other measurements for this example are shown in Table 1.

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