JPS5951905A - New ethylene copolymer - Google Patents

Abstract

PURPOSE:An ethylene/alpha-olefin copolymer excellent in various properties (tensile strength, impact resistance, environmental stress, cracking resistance, heat resistance etc.) and processability, having a specified density and a specified intrinsic viscosity. CONSTITUTION:An ethylene/alpha-olefin copolymer (the alpha-olefin having 4-18 carbon atoms) having the following properties: density of 0.85-0.945g/cm<3>, intrinsic viscosity [eta] which is 0.5-0.9 time as high as that of an ordinary linear ethylene/alpha-olefin copolymer of the same melt index; terminal vinyl group content of at least 0.2/1,000 carbon atoms; MW distribution (Mw/Mn) of below 5; melt index ratio of at least 40; and melt index of 0.05-10. This copolymer is produced by adding about 0-50ppm of an antioxidant to a copolymer solution prepared in the usual manner by using a Ziegler catalyst, then removing the solvent by flashing, extruding the produced molten copolymer through a vent type blendor/extruder at about 180-300 deg.C and kneading the extrudate in a Banbury mixer several times.

Description

DETAILED DESCRIPTION OF THE INVENTION This invention relates to copolymers of ethylene and d-olefins having improved processing.

Linear medium-low density polyethylene produced by copolymerization of ethylene and α-olefin has a lower density of 11<, tensile strength, and tear strength than that of conventional highly branched melon produced by high-pressure radial polymerization. strength, impact resistance,
Environmental stress cracking resistance (ESCRSC) Excellent physical properties such as heat input and hot tack properties during sealing.

Butene-1 is usually used as the α-olefin.
However, α-olefins and higher α-olefins having 5 to 18 carbon atoms
It is also possible to use the monthly resin for convenience, and in this case, the excellent physical properties of the above material are further improved.
).

Therefore, films molded using this linear medium-low density polyethylene, various products such as injection molded products, blow molded products, extrusion molded products, rotary molded products, etc., have excellent physical properties and are new. In addition to developing new applications, it can fully compete with conventional products made of high-pressure low-density polyethylene, and its excellent physical properties make it possible to down-gauge, and it has industrial value from the viewpoint of resource and energy conservation. is high.

However, such linear medium-low density polyethylene
In general, the moldability is inferior to that of high-pressure low-density polyethylene, and various troubles occur when processing it using processing machines that are used for high-pressure low-density polyethylene.
This is causing the problem of reduced processing productivity.

Specifically, the melt tension is low, the melt elasticity is low, and the current load of the motor during extrusion is high, resulting in poor productivity in blow molding, extrusion molding, and film molding, and the production of a wide variety of products. In addition, there are industrial disadvantages such as the need to adjust the molding conditions to narrow conditions during processing.Also, in extrusion coating, neck-in is large;
This causes a big problem in that both ends of the film become thick.

In order to overcome these problems, it is necessary to modify the machine to a special specification, which is an economic disadvantage.

The present inventors discovered that ethylene, which has particularly excellent physical properties, and 41 carbon atoms
'(℃ for the copolymer with α-olefin of Ishi 18,
This is the result of research into ways to improve these drawbacks and to obtain improved copolymers.

I arrived at this invention.

In other words, the density of ``Kineyu'' is 0.850'' and 0.945.
7A, the intrinsic viscosity [η] is 1,000 η for the intrinsic viscosity [η] of linear ethylene-α-olefin copolymers with the same melt index]/[η17=0.5 to 0
．． 9, and the terminal vinyl content in the copolymer is (
) is a copolymer of ethylene and an a-olefin having 4 to 18 carbon atoms, characterized in that the carbon number is 2/1000 or more.

The copolymer of the present invention is characterized in that it exhibits a significantly lower intrinsic viscosity than ordinary copolymers even with the same melt index.

Highly branched polyethylene produced by a high H-radical polymerization method has a significantly lower intrinsic viscosity than a linear low-density ethylene-α-olefin copolymer even if the polyethylene has the same melt index. This is because high-pressure low-density polyethylene is a long-chain branched polymer with many long-chain branches, and in solution it has a lower intrinsic viscosity than a linear polymer, and the molecular spread is smaller. It is thought that -C (7・ru.

From this, it is suggested that the copolymer of "Dud" has long chain branches in addition to short chain branches due to the a-malefin comonomer.

A co-11 combination of ethylene and one-olefin suggesting the presence of long chain branching has been proposed in JP-A-53-92887.
The polymers described in the Examples of that patent are described in the Comparative Examples.

Compared to the conventional linear copolymer, the intrinsic viscosity is almost the same when the melt index is the same, and there is no evidence that the intrinsic viscosity of the copolymer of the patent example is lower. .

Therefore, it can be said that the copolymer of the present invention and the copolymer of the patent have completely different structures and different melt viscosity behavior, and are also an improvement of the copolymer of the patent. The characteristics of this invention are transparency, impact resistance, and tear resistance, and the moldability, which is an improved effect of the present invention, is not mentioned at all.
It is clear that the technical idea of the present invention is completely different from that of the patent.

Furthermore, the copolymer of this patent is characterized by having multiple maximum melting points, whereas the copolymer of Kinei's copolymer has a single melting point, which is a large crystal + 14 structure difference. .

The density of the copolymer of the present invention is 0.850-U, 945
”, in the range of 1lcrri'. o, s s o
If it is less than y/d, the rigidity is low, and if it is more than 0.940 WAd, the impact resistance and tear strength are poor.

The intrinsic viscosity [η] of the copolymer of the present invention is determined by the ratio [η″l/
/Lη]1=o,s is in the range of ~0.9.

In particular, [phosphorus [η]l is preferably in the range of 05 to 0.8.

If it is 0.9 or more, the effect of the present invention is hardly observed, while if it is 0.5 or less, the physical properties, especially the impact resistance, are too low.

The melt index (MI) of the normal linear ethylene-α-olefin copolymer used for comparison and 13
The intrinsic viscosity [η] measured with a decalin solution at 5°C has the following relationship.

[η] =・-1,08log MI + 2. OO
Therefore, the intrinsic viscosity of the copolymer of the present invention is in the following range.

0.5 (-1,08JogMI+2.OO), 4 (
η]4 0.9 (-1,08jogMI+2.00
) Another feature of the present invention is that the molecular weight distribution (MW/W') measured by gel permeation chromatography (GPCJ) is narrow, with a ratio of weight average molecular weight to number average molecular weight of 5 or less. Despite this, the melt index ratio (MI
R: Ratio of melt index when load is 3i21.6kl and melt index when load is 2.16kyO)
is much larger than normal linear medium-low density polyethylene. The preferred range of MIR of the copolymer of the present invention is 40 or more.

The melt index of the copolymers of the invention is from 0.05 to 100, preferably from 0.05 to 10. If it is less than 005, the fluidity will be poor, and if it is more than 10, the impact resistance will be reduced.

The terminal vinyl bond in the copolymer of the present invention is 0.2/1000 carbons or more, preferably (13(IL'1o
o.

More than carbon. With a copolymer having few terminal vinyl bonds, it is difficult to obtain a copolymer having the characteristics specified by the present invention, and the obtained copolymer has
Poor extrusion processability.

The a-olefin used in the present invention has 4 carbon atoms.
to 18, particularly preferably those having 6 to 8 carbon atoms. Of course, two or more types of a-olefins may be used simultaneously.

Specific examples of d-olefins include butene-1, pentene-1
, hexene-1,4-methylpentene-1, hegetene-1
1, octey-1, nonane-1, decene-1, etc.

The method for producing the copolymer of the present invention will be explained below.

In particular, the important conditions for producing the copolymer of the present invention are not only the polymerization conditions but also the conditions for separating the copolymer from the yarn and the subsequent cross-firing.

The catalyst used in the polymerization is not particularly limited and any known Ziegler catalyst can be used.
Transition metal balogenides of groups V to ■, organoalkyl aluminum-magnesium complexes such as alkylaluminum-magnesium complexes, alkyl alkoxyaluminum-magnesium complexes, organoaluminums such as alkylaluminum or alkylaluminum cumylides, etc. A Ziegler catalyst or the like consisting of a combination with an organometallic compound of Groups 1 to 2 is used.

As for the polymerization method, the terminal vinyl bond content of the copolymer is 0.
．． Conditions are selected such that the number of carbon atoms is 2/1000 or more. Generally, the higher the polymerization temperature, the higher the vinyl content tends to be, and therefore a process that allows BJ polymerization at high temperatures is selected. Specifically, the polymerization pressure is 20 to 10
Solution 1 method, in which polymerization is carried out in an inert solvent at 00 atm and a polymerization temperature of 110 to 300 °C, by feeding a Ziegler catalyst into a conventional high-pressure polyethylene plant.
It is produced by a process such as a high-pressure method at a polymerization temperature of 150° C. to 300° C. at 0.00 atm.

The density of the copolymer is uniquely determined by the content of α-olefin in the copolymer. In addition, the content of the olefin in the copolymer is determined by the amount of unreacted ethylene and σ in the polymerization system.
-Since it is almost uniquely determined by the molar ratio of olefins, it is possible to control the α-olefin content and the density of the comonomer by changing the feed ratio of ethylene and α-olefin and the polymerization conversion rate. be.

One method for obtaining a copolymer of the present invention having a lower intrinsic viscosity than ordinary linear copolymers will be described below.

The polymer solution obtained by polymerizing ethylene and mono-olefin by the above solution polymerization method or the high polymerization method is heated, and then flanched to remove the solvent to obtain a bath melt copolymer. . At this time, the antioxidant concentration (squid,
Even if added, the amount should be kept to about 50 pHIn or less relative to the copolymer.

The molten polymer is heated to 180° to 300°C using a vented kneading extruder.
extruded at a temperature of , and then repeatedly kneaded in Banbury.

The important conditions for keeping the intrinsic viscosity of the co-11(f) body to be 1 ゛ lower than the intrinsic viscosity of ordinary CM and chain copolymers are:
These include the presence or absence of the antioxidant mentioned above, the added concentration, and the cross-mixing conditions, such as the number of kneading times in the cross-mixer. Low amount of antioxidant 1.
[The higher the number of times of kneading, the lower the intrinsic viscosity. Therefore, the copolymer of the present invention can be obtained by controlling the antioxidant concentration and crosstalk conditions.

The copolymer of the present invention has excellent impact resistance, tear strength, hot tack properties, and ESCH compared to high-pressure low-density polyethylene, and has higher melt tension and melt elasticity than ordinary linear low-density polyethylene. Molding processability is much improved compared to conventional copolymers by reducing the motor load during extrusion and reducing neck-in, making it suitable for extrusion molded products such as films and pipes, hollow molded products, electric wire coatings, and extrusion coatings. This copolymer is suitable for applications such as

The copolymers of the present invention also contain, of course, the usual stabilizers, UV absorbers, antistatic agents, antiblocking agents, pigments, inorganic or organic fillers, rubbers and other small amounts of polymers normally added to polyolefins. Substances can be added. Examples of these additives include BHT, Shell Ionox 330, Gutudryte 3114, and Ciba Geigy Irganox 1oxo.
, 1076, Tinuvin 327, Norl L manufactured by Sankyo Pharmaceutical Co., Ltd.
S770.1) MTP, I) LTI) P, silica, calcium stearate, zinc stearate, erucic acid amide, oleic acid amide, titanium white, calcium carbonate, carbon black, Merck, nutylene-butane diene rubber, ethylene-vinegar Examples include bicopolymers, high-density polyethylene, high-pressure polyethylene, and polypropylene.

The present invention will be described below with reference to Examples, but the present invention is not limited to these Examples. 1f. The meanings of terms used in the examples are as follows.

+++Mr; represents melt index, ASTM
l) -1238, temperature 190℃, load 216
Measured under floor conditions.

+IIIMIR; Under M I measurement conditions, load 21
, 6 means the quotient divided by MI. It is a measure of liquidity. MIR is practically molded and has good fluidity.

(Density: Measured at °C according to JIS K-6760.

(Double bond in IV; absorption of 964, 908, and 888 cm-' for each bond of 3° transvinylene, Songtan vinyl, and vinylidene measured by extra-absorption analysis using a thin film assembly made by compression molding, respectively) and expressed as their total.

(1 Comonomer content: The amount of copolymer components contained in 1 copolymer is measured by C1C13N.

(vl) Bath melt tension; rheometer, temperature 1901: Pushinger speed 2. It was extruded using OrgrhZ and stretched using this Nutland '4 l Q m/wR, and the tension at that time was taken as the melt tension.

vll) Dice well; outer diameter 15a, inner diameter] 0III1
Use of blow molding die, temperature] Expressed in weight per 20 pieces of Valinone extruded at 70°C.

(vilD tensile impact strength; ASTM D-1822iC
Therefore, it was measured.

0XIESCR; Indicates environmental stress fracture resistance. A.S.
The temperature was measured in accordance with TMD-1693. The temperature was 80° C., and the concentration of nonionic surfactant was 100%. It is expressed as the time it takes for 50% of the test pieces to break.

(x) Intrinsic viscosity ([η]); Measured at 135° C. using a viscosity tube in a risecalin solvent.

Flash) Strand smoothness: Using a rheometer, the strand was extruded at a shear rate of 100 sec-1, and the surface smoothness was visually determined. ○ indicates a smooth strand with a constant diameter, Δ indicates a dry strand, and the strand diameter changes periodically or non-periodically;・Things that generate Shiracha.

IKII extrudability: A hollow molding die with an outer diameter of 16 mm and an inner diameter of 10 m is attached to a 50aφ Pro-1 molding machine manufactured by Plako Co., Ltd.
The resin was extruded at a set temperature of 180°C and a screw rotation speed of 46 rP. The extrusion rate (〃Seki) and the load current (ampere) were measured, and the extrusion property = extrusion rate/load current (W/IR'!・ampere) was determined.
) ; Measured using a Waters GPC150c at ℃.

(1×) Melting point; measured using Perkin Elmer type 2 (DSC).

(11 Synthesis of solid catalyst for polymerization il+ Solid catalyst A After removing oxygen and moisture inside the autoclave with dry nitrogen, 1.51 ml of a hexane solution of 0.4 mat/l of trichlorosilane and 1.21 ml of hexane were charged.
The temperature was raised to 70°C. Next, AJo-+s Mg (n-B
u)+-ys(Q-nBu)o,t (metal concentration 0
．． 8 mol/l octane solution) o, 4s,,e
and hexane o, 3sJ? was introduced at 60°C over 15 hours.

Furthermore, 70.61 liters of hexane containing 40.7 ml of TiCl was introduced, and the reaction was carried out at 70° C. for 1 hour. Furthermore, A.I. ,,5
Mg(n-Bu)tots(0-nBu)cby was produced according to Japanese Patent Application Laid-Open No. 57-5709.

The reaction mix tube was filtered and washed with hexane. This is called solid catalyst A.

(2) Solid catalyst B In the same manner as +11, Al0-11-r5g (n-B
u)r, t5(0-nBu)(>q460mmol
and trichlorsila/400mm0j and vanadyl trichloride 8
．． 8 ryunoj, titanium tetrachloride l 2 mmol
Synthesis was performed by This will be referred to as solid catalyst B.

Example 1 1 (In a polymerization vessel with a stirrer having a capacity of 1Q-e, solid catalyst A was added at 1.5 Vklr and the concentration was 0.1
A solution of triethylaluminum in cyclohexane with a ratio of l/l to 2001/I (r + ethylene at 20 kf/Hr,
As comonomers, octene-1 was continuously supplied at 16 ki/Hr and hydrogen was continuously supplied at 0.1 kl/Hr, and the polymerization temperature was 2.
00℃, pressure lo o ) qtlct! Polymerization was carried out using The polymerization conversion rate of ethylene was about 80%, and the amount of copolymer produced was about 17 kl/Hr.

The copolymer solution was continuously fed to a flash tank maintained at 5 atm and 230°C, where unreacted ethylene and Oct.7
-1 and about 90% of the solvent cyclohexane were removed.

The flash tank can be heated using steam tracing to maintain the set temperature and pressure.

The concentrated polymer solution was kneaded at 230° C. in a 44+uφ vented twin-screw extruder, and most of the unreacted monomers and solvent were evaporated from the vent. Attach the pelletizer to the tip of the extrusion 1. The copolymer was obtained in the form of pellets.

The copolymer pellet still contained 3% by weight of volatile components such as solvents.

The obtained copolymer pellet was heated at 200°C in Banbury.
After kneading for 20 minutes, the mixture was pelletized using a sheet pelletizer. 11,000 pp of Irganox 1010 was added as an antioxidant to the obtained pellets, mixed in a Henschel mixer, and then passed twice through a 65 wau φ twin-screw extruder at 230° C. to obtain a copolymer of the present invention.

The density of the copolymer is 0.920 fl/cry? Octene-1 content 11.5% by weight, melt index 1.
5y/l (fund) MIR68, GPC MW/MN = 4
．． 0, terminal vinyl bond gold content is 0.35/1000
Carbon had an intrinsic viscosity of 1.32. In addition, the melting point of the crystal is 124°C, a single peak, and 110°C.
A gentle mountain could be seen nearby.

A DSC chart is shown in FIG.

The intrinsic viscosity of linear copolymers with the same melt index is given by the above equation (η) = 1.08 log
From M I +2.00, [η)4=tsi is calculated. I want to, [η]/[η],! =0.73 and 1. The properties of the copolymer are shown in Table 1-J-6 Example 2 Co-1 was prepared in the same manner as in Example 1 except that 4-methylpentene-1 was used instead of octene-1 as the comonomer.
Synthesized the union.

The density of the obtained copolymer is 0.925 W/c-rr
? , 4-methylpentene-1 content 95%, melt index/< 1.077109, MIR65, G
PC MW/MN-38, terminal vinyl bond gold content 0.3
5iV1000 carbon, the intrinsic viscosity was 150. Therefore, [ηn[η]l was 0.75. The highest melting point of the crystal was 125°C, with a gentle peak at 111°C. The properties of the copolymer are shown in Table 1.

Example 3 Hexene-1 instead of octene-1 was used as a comonomer.
Except for using 1 and setting the polymerization temperature to 190℃,
A copolymer was synthesized in the same manner as in Example 1. The obtained co-M (density of coalescence is 0.919 p-/d, hexene-
Contains 1! 9.03fU factory%, melt index o, 6
．． MIR58, GPC (1) MWIMN = 4
．． 1. Terminal vinyl bond content i0.35/1.000
Carbon, ultimate □viscosity was 1.78. However, [η]/[η)l===o, s.

Further, the highest melting point of the crystal was 122°C, which was a single peak, and a 7-drop peak was observed around 106°C. The properties of the copolymer are shown in Table 1.

Example 4 Hexene-1 instead of octene-1 was used as a comonomer.
1. Mixed α-olefin of octene-1 and decene-1 (manufactured by Mitsubishi Chemical Corporation, Diarene 610°Hexeno-136
%, octene-133%, decene-1,31% mixture d
The copolymer was prepared in the same manner as in Example 1, except that -olefin 9 was used.

The density of the obtained co-monomerization is 0.93] p-/err?
, Melt Index, Z1. l, MI R79, GPC
MW/MN=3.9, terminal vinyl bond content i 0.3
04a//l O00 carbon, intrinsic viscosity was 1.39. Therefore, [η]/[η]l is 0.71. In addition, the highest melting point of the crystal is a single peak of 125°C,
A gentle peak was observed near 116°C. The properties of the copolymer are shown in Table 1.

Example 5 ] Solid catalyst B was added to a polymerization reactor with a stirrer having an amount of 00 J], 57/■-1r, concentrated KO, (175 nrn
oi/l tri-inphthyl aluminum cyclohexane bath solution.

1/l-Ir, ethylene 20 ky, /Hr, octene-1 10kli':/l Ir, hydrogen 0.2
The polymerization was carried out at a polymerization temperature of 200° C. and a pressure of 200 ψd, by continuously supplying kg at 7 hours.

The polymerization conversion rate of ethylene was approximately 80%, and the amount of copolymer produced was approximately 17 k1/■ (r).
The unreacted ethylene, the comonomer octene-1, and the solvent hexane were removed by evaporation. The copolymer melt from which most of the volatile matter had been removed was kneaded and extruded at 230° C. in a vented twin-screw extruder with a diameter of 44 mm to remove the volatile matter. The obtained copolymer pellet was heated at 200°C at 20°C in Banbury.
After melting and kneading for minutes, add 110% of Irganosotas 1010
00pp added. The mixture was uniformly mixed by passing it twice through a 2@ extruder with a diameter of 65 at 230° C. to obtain a copolymer of the present invention.

The density of the copolymer is o, 923 'teem', melt index 5.3 V-/10, MIR 43,
GPC MW/MN = 3.9, contains terminal vinyl bond! The number of carbon atoms was 0.36/1000, and the intrinsic viscosity was 0.73. Furthermore, the highest melting point of the crystal was a single peak at 124°C, and a gentle peak near 109°C was observed. The properties of the copolymer are shown in Table 1.

Example 6 Budene-1 instead of Octene-1 as comonomer
A copolymer was obtained in the same manner as in Example 5 except that hydrogen was continuously supplied at 0.1 kfb/Hr.

The density of the copolymer is o, g 1 s 7/crr? , melt index y! ,, ]7/10 run, M,
IR69, GPC MW/MN=4.3, terminal vinyl bond gold content was 0.32/1000 carbons, and intrinsic viscosity was 154. The melting point of the crystal was a single peak of 122°C, and a gentle peak was observed around 111°C. The properties of the copolymer are shown in Table 1.

Comparative Example 1 A cyclohexane solution having a yield of 1.57/Hr -) rietheraluminum of 0.1 mmol// was added to a reactor with a stirrer having a capacity of 100, d at 2004/Hr. , ethylene was continuously supplied at 20 kV'Hr, octene-1 was continuously supplied as a comonomer at 1 Okf/Hr, the polymerization temperature was 200°C, and the pressure was No Okf/cr.
r? Polymerization was carried out using

The polymerization conversion rate of ethylene was about 80%, and the amount of copolymer produced was about 17 kII7/Hr. After mixing 2000 ppm of Irganox 1010 (antioxidant) per copolymer into the copolymer solution that came out of the polymerization vessel, it was continuously supplied to a flash tank maintained at 5 atm and 230°C. , volatiles were removed. The copolymer melt from which most of the volatile matter had been removed was passed through a vented twin-screw extruder with a diameter of 44 at 230°C to remove the volatile matter and obtain a pellet-shaped copolymer.

The obtained copolymer pellets were pulverized and vacuum dried at 100° C. to completely remove residual volatile components.

The density of the obtained copolymer is 0.920 ft/cm',
Melt index 1.0 i/l 01011. M
I R28, GPC MW/MN = 3.5, terminal vinyl bond 0.33/1000 carbons, intrinsic viscosity 2.0
It was 1. [η] / [η]! Medium 1.0, MIR
This copolymer is a linear copolymer because of its small diameter. Further, the highest melting point of the crystal showed a double peak at 119°C and 124°C, and a gentle peak was observed around 106°C.

The DSC curve is shown in Figure 2. The first property of the copolymer is
Shown in the table.

Comparative Example 2 A copolymer was synthesized by the method of Comparative Example 1, except that solid catalyst B was used instead of solid catalyst A.

The density of the obtained copolymer was 0.9 z s tld, melt index 0.6f/lOWR1MIR26, G
MW/MN of PC = 3.3, terminal vinyl bond 0.
31 (1i!il/1000 carbon, intrinsic viscosity 2.44'
C: Yes. [η]/[η]l is 1.1, and MIR
This copolymer is a linear copolymer because of its small diameter. Furthermore, the melting point of the crystal had peaks at 122°C and 124°C, and a gentle peak was observed around 111U.

The performance of the copolymer is shown in Table 1.

Comparative Example 3 Performance was evaluated using polyethylene M-1820 manufactured by Asahi Dow Co., Ltd. manufactured by high-pressure radical polymerization as a comparative example. The results are shown in Table 1.

margin below

[Brief explanation of the drawing]

FIG. 1 shows the DSC curve of the copolymer of Example 1, and FIG. 2 shows the DSC curve of the copolymer of Comparative Example 1. Patent applicant: Asahi Kasei Industries, Ltd.

Claims (1)

[Claims] (1) Density 0.850 to 0.945'//(1n",
Intrinsic viscosity [η] of linear ethylene-α-olefin copolymers having the same melt index [
A copolymer of ethylene and an a-olefin having 4 to 18 carbon atoms (21 Terminal vinyl content in copolymer is 0.2@710
Copolymer (3) according to claim 1, which is 0 (+ carbon or more lh) The ratio of the average molecular weight to the number average molecular weight ('MW
The copolymer according to claim 1 or 2, wherein □(
4) The copolymer according to claim 1, item 2 or 3, which has a melt index ratio (MIR) of 40 or more. (5) A melt index of 0.05 to 10. Copolymer (6) linear ethylene-a-olefin having the same intrinsic viscosity [η] and the same melt index For the intrinsic viscosity [η]l of the copolymerized valley body, [η]/[η)6= o, s~
Claim 1 characterized in that it is in the range of 0.8.
．． Copolymer according to item 2+'3+4 or item 5