JP2919521B2 - Hexene-1 copolymer - Google Patents

Description

The present invention relates to a hexene-1 copolymer. More specifically, the present invention relates to a copolymer of hexene-1 having a specific structure and another α-olefin.

(Prior art)

Syndiotactic polypropylene has long been known for its existence, but conventional methods of low-temperature polymerization with a catalyst consisting of a vanadium compound, ether and organoaluminum have poor syndiotacticity, which is characteristic of syndiotactic polypropylene. It is hard to say that it expresses, much less the copolymer of olefin and propylene is hard to say crystalline polypropylene. On the other hand, JAEWEN et al. Discovered for the first time that a transition metal catalyst having an asymmetric ligand and a catalyst composed of an aluminoxane could produce polypropylene with good tacticity such that the syndiotactic pentad fraction exceeded 0.7. (J. Am. Chem. Soc., 1988,
110,6255-6256).

On the other hand, according to the present inventors, it has been found that polyhexene-1 having high syndiotacticity can be obtained by polymerizing hexene-1 using a high purity catalyst.

[Problems to be solved by the invention]

By using the catalyst of JAEWEN et al., Polyhexene-1 having good activity per transition metal and high tacticity of the obtained polymer can be obtained, but a copolymer of hexene-1 having a syndiotactic structure is obtained. It can be expected to have unprecedented properties and can be expected as a blend material with other polyolefins.

[Means for solving the problem]

The present inventors have proposed a new structure of hexene-1 for the above purpose.
The present invention was completed by diligently searching for a copolymer of

That is, the present invention relates to ¹³ C-NMR measured in a 1,2,4-trichlorobenzene solution, wherein the absorption of a methylene group in a side chain directly bonded to the main chain of hexene-1 unit is based on tetramethylsilane. The absorption intensity of the peak attributed to the racemic structure observed at 34.4 ppm is not less than 0.3 of the total absorption intensity of the methylene group of the side chain directly bonded to the main chain observed at 34.4 to 35.3 ppm, 1 is 50 wt% to 99.
9% by weight of hexene-1 and hexene having 2 to 25 carbon atoms
A hexene-1 copolymer having a syndiotactic structure having an intrinsic viscosity of 0.05 dl / g or more as measured with a tetralin solution at 135 ° C., which is a copolymer with an α-olefin other than 1.

Examples of the catalyst used for producing the other α-olefin copolymer of hexene-1 of the present invention include the compounds described in the above-mentioned documents, but a homopolymer of hexene-1 may have a different structure. When the is produced, of the resulting polymer
^{In 13} C-NMR, of the absorption of the methylene group of the side chain directly bonded to the main chain of hexene-1 unit, the absorption intensity observed at 34.4 ppm based on tetramethylsilane is 34.4 to 35.3 ppm.
It is possible to use a catalyst system which gives a polymer having a relatively high tacticity with an absorption intensity of the total absorption of the methylene group of the side chain directly bonded to the main chain of 0.5 or more, for example, an asymmetrical arrangement. A catalyst system comprising a transition metal compound having a ligand and an aluminoxane is effective.

As a catalyst system suitable for producing the copolymer of the present invention, isopropyl (cyclopentadienyl-1-fluorenyl) hafnium dichloride or isopropyl (cyclopentadiethyl-1-fluorenyl) zirconium dichloride described in the above-mentioned literature is used. And the aluminoxane has a general formula: (Wherein R is a hydrocarbon residue having 1 to 3 carbon atoms). In particular, methylaminoxan wherein R is a methyl group and n is 5 or more, preferably 10 or more is used. Is done. The use ratio of the aluminoxane to the transition metal catalyst is 10 to 100,000,000 times, usually 50 to 5000 times. The polymerization conditions are not particularly limited, and a solvent polymerization method using an inert medium, a bulk polymerization method substantially free of an inert medium, and a gas phase polymerization method can be used. The polymerization temperature is -100 to 200 ° C, and the polymerization pressure is normal pressure to
Generally, it is performed at 100 kg / cm ² . Preferably -100 to
100 ° C, normal pressure ~ 50 kg / cm ² .

As the α-olefin used in the present invention, in addition to ethylene, a general formula H ₂ C ＝ CH— (CH ₂ ) _n —CH ₃ (where n is 0,
An integer of 1, _{2, 4 to} 22) or-(CH ₂ ) _n -CH ₃
Has a branched structure, etc., and has 2 to 25 carbon atoms. Specifically, propylene, butene-1, pentene-1, heptene-1, octene-1, nonene-1,
Linear α-olefins such as decene-1, undecene-1, dodecene-1, tridecene-1, pentadecene-1, hexadecene-1, heptacene-1 and octadecene-1, or 3-methylbutene-1,4-methylpentene Examples are branched α-oleins such as -1,4,4-dimethylpentene-1.

In the present invention, what is important is that the polymerization ratio of hexene-1 and α-olefin is 0.1 to 50% by weight in terms of α-olefin content.
The amount of the monomer introduced into the polymerization system was controlled so as to obtain a hexene-1 unit directly by the ¹³ C-NMR measured with a 1,2,4-trichlorobenzene solution of the copolymer. Of the absorption of the methylene group of the bonded side chain, the absorption intensity observed at 34.4 ppm based on tetramethylsilane is 34.4 ppm.
It is produced by controlling the monomer ratio, polymerization temperature and the like so that the absorption intensity of the total absorption of the methylene group of the side chain directly bonded to the main chain observed at 35.3 ppm is 0.3 or more.
The pattern of the absorption spectrum of the methylene group, which is considered to be caused by the steric structure of hexene-1, has not been known so far, and it is considered that this characterizes a copolymer having unprecedented physical properties.

The molecular weight of the copolymer in the present invention is not particularly limited as long as it can be used as a normal polymer, but is usually 0.05 dl / g as the intrinsic viscosity measured at 135 ° C. in a tetralin solution from the viewpoint of being used as a molding resin. As described above, the number average molecular weight in terms of propylene measured by gel permeation chromatography is about 1000 or more.

〔Example〕

 Hereinafter, the present invention will be described with reference to Examples.

Example 1 Isopropylcyclopentadienyl-1-fluorene synthesized by an ordinary method in an autoclave having an internal volume of 300 ml was lithiated, reacted with zirconium tetrachloride, and further purified to obtain isopropyl (cyclopentadienyl-1).
-Fluorenyl) zirconium dichloride 5 mg and Toyo Akzo Co., Ltd. methylaminoxan 0.67 g having a degree of polymerization of about 16
Is dissolved in 150 g of hexene-1 and 10
After inserting 0 g, the mixture was stirred at 30 ° C. for 2 hours. Unreacted propylene was purged, a large amount of methanol was added and the mixture was filtered off, and dried at 80 ° C. under reduced pressure to obtain 180 g of a polymer. In ¹³ C-NMR measured with a 1,2,4-trichlorobenzene solution, the absorption intensity observed at 34.4 ppm based on tetramethylsilane was 34.
It is 0.65 with an absorption intensity of 4 to 35.3 ppm, and propylene is 30.5
wt%. In addition, the intrinsic viscosity (hereinafter referred to as η) measured at 135 ° C. tetralin solution is 0.71 dl / g, and is 1,2,4 at 135 ° C. by gel permeation chromatography.
-The ratio of the weight average molecular weight to the number average molecular weight (hereinafter referred to as MW / MN) measured with a trichlorobenzene solution was 2.1.

A 1 mm press sheet was prepared and the following physical properties were measured.

・ Tensile yield strength: kg / cm ² ASTM D638 (23 ° C) ・ Elongation: ASTM D638 (23 ° C) ・ Izod (with notch) impact strength: kg ・ cm / cm ASTM D256 (23 ° C, -10 ° C) ・Haze:% According to ASTM D1003.

Tensile yield strength is 1kg / cm ² , elongation is 67%, Izod impact strength is more than 80kgcm / cm at both 23 ℃ and -10 ℃.
Haze was 23%.

Example 2 A propylene content of 10.7 was obtained in the same manner as in Example 1 except that the amount of hexene-1 used was 95 g and the amount of propylene was 10 g.
65 g of a wt% copolymer was obtained. 34.4 ppm measured by ¹³ C-NMR
The absorption intensity observed at 34.4 to 35.3 ppm
0.78, η was 0.81 dl / g, and MW / MN was 2.2.

Example 3 The procedure of Example 2 was repeated, except that 5 g of ethylene was used instead of propylene, to obtain 72 g of a copolymer having an ethylene content of 4.8 wt%. ^The absorption intensity observed at 34.4 ppm measured by ¹³ C-NMR is 0.65 of the absorption intensity of 34.4 to 35.3 ppm, and η is 0.6
It was 3 dl / g and MW / MN was 2.1.

Example 4 The same procedures as in Example 2 were carried out except that butene-1 was used instead of propylene, and 62 g of a copolymer having a butene-1 content of 7.5 wt% was obtained.
I got ^The absorption intensity observed at 34.4 ppm measured by ¹³ C-NMR is 0.72 of the absorption intensity of 34.4 to 35.3 ppm, and η is
0.48 dl / g and MW / MN was 2.0.

〔The invention's effect〕

The copolymer of the present invention can be expected to be used for various uses and is extremely valuable industrially.

Claims (1)

(57) [Claims] 1. The absorption of a methylene group of a side chain directly bonded to the main chain of hexene-1 unit, determined by ¹³ C-NMR measured with a 1,2,4-trichlorobenzene solution, is 34.4% based on tetramethylsilane. The absorption intensity of the peak attributed to the racemic structure observed at ppm is 34.4-35.3 ppm of the total absorption intensity of the methylene group of the side chain directly bonded to the main chain observed at 34.4-35.3 ppm.
3 or more, and the content of hexene-1 is 50 wt% to 99.9 wt%
Is a copolymer of hexene-1 and an α-olefin other than hexene-1 having 2 to 25 carbon atoms, and has a syndiotactic structure having an intrinsic viscosity of 0.05 dl / g or more measured at 135 ° C. in a tetralin solution. Hexene-1 copolymer having the same.