JPS59227913A - Production of ethylene polymer or copolymer - Google Patents

Abstract

PURPOSE:To make it possible to produce continuously an ethylene (co)polymer excellent in mechanical strength, moldability, etc., at a high production rate for a long time, by effecting the polymerization in three stages in each of which the operation condition is specified. CONSTITUTION:An ethylene (co)polymer of an intrinsic viscosity eta of 2.5- 5.2dl/g and a density of 0.939-0.965g/cm<3> is produced by three-stage polymerization comprising a step of producing 5-23wt%, based on the total polymer formed, ethylene (co)polymer having a content of alpha-olefins other than ethylene <=0.5wt% and an intrinsic viscosity eta of 11-26dl/g at 50-80 deg.C by using a catalyst composed of a solid catalyst component containing Ti, Mg and a halogen and an organoaluminum compound; a step of producing an ethylene copolymer having a content of alpha-olefins other than ethylene <=0.5wt% and an intrinsic viscosity eta of 0.25-1.6dl/g at 70-100 deg.C; and a step of producing an ethylene copolymer having a content of olefins other than ethylene of 2-30wt% and an intrinsic viscosity eta of 2.9-5.1dl/g at 60-90 deg.C, wherein these steps can be carried out in any desired order, and wherein the weight ratio between the polymers formed in steps B and C is 1:0.5-1.5.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing an ethylene polymer or a copolymer thereof, and more specifically, a method for producing an ethylene polymer or a copolymer thereof with excellent mechanical strength and moldability for a long time with high productivity. This invention relates to a method that can be manufactured continuously for a period of time.

Generally, high-density ethylene polymers are produced using Ziegler type catalysts, and those with high molecular weights are produced in order to improve the mechanical strength of products. In this case, if the distribution of product molecules is narrow, fluidity will be poor during molding, leading to a decrease in productivity, and the resin pressure at the molding pot will increase, so it is necessary to increase the required strength. 0 In this case, two stages of conventional ethylene polymerization fljl! i'
Attempts have been made to obtain products with a wide molecular distribution by dividing the process into i or more steps. However, by multi-stage polymerization method! ! The produced ethylene polymer has a lower die swell than normal ethylene polymer, so
In the case of blow molding, the thickness 1r;I- becomes thinner, making it difficult to obtain a product of constant quality.

In order to adjust the wall thickness, it is necessary to replace the die, which reduces productivity and is industrially disadvantageous. In addition, there were various problems such as poor moldability due to low melt tension.

Therefore, the present inventors conducted extensive research into a method for efficiently producing ethylene polymers or copolymers with excellent physical properties by solving the above-mentioned problems, and as a result, identified the requirements for each process and developed five steps. The inventors discovered that the object could be achieved by polymerization and completed the present invention.

That is, the present invention comprises (A) a solid catalyst component containing at least titanium, magnesium and halogen; and (B)
3 using a catalyst whose main component is an organoaluminium compound.
In a method for producing an ethylene polymer or copolymer by step polymerization, as the first step, (a) step: At a temperature of 50 to 80°C, 0.5% by weight of at containing other α-olefins is added. A step of producing an ethylene polymer or copolymer having the following properties and having an intrinsic viscosity [η] of 11 to 26 dl19- in a proportion of 5 to 23% of the total polymerization amount is carried out, followed by (b) Process: At a temperature of 70 to 100°C, the content of other α-olefins is 0.5% by weight or less, and the intrinsic viscosity [η] is 0.25 to 1. d e
Step (0) of producing an ethylene polymer or copolymer of 1/1/ff: At a temperature of 60 to 90°C, the other α-olefin content is 2 to 30% by weight, and The two steps of producing an ethylene copolymer having an intrinsic viscosity (v) of 2.9 to 5 Adl/9- are carried out in any order, and the ratio of polymerization 111 in step (b) and step (c) is ( b) Process: (
C) Step=1: Intrinsic viscosity [η) characterized by polymerization to be 0.5 to 1.5 2. J5~5.2
#/7, density 0.939-0.965f/cy/I
The present invention provides a method for producing an ethylene polymer or copolymer.

The catalyst used in the present invention is a catalyst whose main components are (A) a solid catalyst component containing at least titanium, magnesium, and halogen, and (B) an organoaluminum compound component. Here, component (A), a solid catalyst component containing at least titanium, magnesium, and a halogen, is obtained by contacting a magnesium compound and a halogen-containing titanium compound, or an addition compound of this compound and an electron donor, stepwise or primarily. It is a composite solid formed by, and various known types can be used without particular limitation. For example, ice can be obtained by reacting a magnesium compound and a chlorine-containing titanium compound with stirring in a hydrocarbon solvent.
No. 52270, qI Publication No. 50-95382, Japanese Patent Application Publication No. 1973
・No. 4-41985, JP-A-55-729.

JP-A-55-13709, JP-A-57-12006.

There are methods disclosed in various publications such as JP-A-57-141409.

As magnesium compounds that can be used in the production of component (A), there are various compounds that are commonly used as carriers for Ziegler type catalysts. For example, magnesium chloride, magnesium bromide, magnesium iodide.

Magnesium halides such as magnesium fluoride.

Hydroxymagnesium halides such as magnesium hydroxide, magnesium oxide, magnesium sulfate, magnesium carbonate, hydroxymagnesium chloride, hydroxymagnesium bromide, hydroxymagnesium iodide, methoxymagnesium, ethoxymagnesium, propoxymagnesium.

alkoxymagnesium, such as butoxymagnesium,
Methoxymagnesium chloride, methoxymagnesium bromide, ethoxymagnesium chloride, ethoxymagnesium chloride.

Alkoxymagnesium halides such as propo-4-simagenesium chloride, propoxymagnesium chloride, bromide, butogishmagnesium chloride, butogishmagnesium bromide, allyloxymagnesium, allyloxymagnesium chloride 1゛, T-lyloxymagnesium bromide, etc. Allyloxymagnesium chloride, as well as methylmagnesium chloride, methylmagnesium bromide, edylmagnesium chloride,
Examples include alkylmagnesium halides such as edylmagnesium bromide, propylmagnesium chloride, propylmagnesium bromide, butylmagnesium chloride, butylmagnesium chloride, and mixtures thereof.

Further, as for the magnesium compound, the above-mentioned one can be used as it is, but it is more preferable to use one modified with silicon 10genide or the like.

For example, a mixture of magnesium dialkoxide and magnesium sulfate modified with silicon tetrachloride and alcohol can be suitably used (Japanese Patent Laid-Open No. 55-40
724).

The 10-gen-containing titanium compound that can be used in the production of component (A) may be a 10-gen compound of divalent, trivalent, or tetravalent titanium. Examples of halogen include bromine and iodine, but chlorine is preferable. For example, titanium tetrachloride (
TiO4) *Titanium trichloride (TiC4),
Adduct of titanium trichloride and aluminum chloride (TiOt,
・1/3 htat, ), dichloromethoxy titanium (
'OH,0Ti04), ? Dichloroethoxytitanium (a, u, oTtc4), l-lichloroproboxytitanium (0,H,0Tia/,s), dichlorodibroboxydicune ((csIto), Tt
c4 ) + dichlorojethoxytitanium ((c2H
,O)2Ttc4), monochlorotriethoxydikune ((c, sl, o), Tlat), etc. ◎trO, In the solid catalyst component of the (Δ) component, the above compound 4', 1 halogen/dikun = Ro ~ 200
(molar ratio) and magnesium/titanium-3 to 9o
It is desirable to mix so that the range of (molar ratio) is ilημ.

θ(, the organoaluminum compound component of component (B) is
A compound having at least one aluminum-carbon bond in its molecule, for example, the general formula Δt.

R, AIJ, RAtX2. R, AtOR, RAt
(OR)X, R3ΔZ? X, etc. (However, R represents an alkyl group or an aryl group having 1 to 20 carbon atoms, and may be the same or different in the same formula, or represents a halogen atom. ) Preferred examples of this compound include jellyaluminum monochloride and diisopropylaluminum monochloride.

diisobutylaluminum monochloride, dioquidylaluminum monochloride, ethylaluminum dichloride, isopropylaluminum dichloride,
Examples include edil aluminum sesquichloride. The amount of component (B) used should be 0.1 to 1000 times the amount of the titanium compound in component (A).

A catalyst containing the above-mentioned components (A) and (B) as main components usually has the ability to produce an ethylene polymer with a titanium per pound of 80 to 4,001.

Among the above catalysts, one of them is JP-A-54-11S169.
No. 1, JP-A-55-40724 and JP-A-55-1
The catalysts disclosed in each publication of No. 49307 are suitable.

The method of the present invention is carried out by polymerizing ethylene in three stages using the catalyst described above.

First, as the first stage of polymerization, the above-mentioned step (a) is carried out, and the temperature conditions for this step are 50 to 50℃.
It should be 80°C. If the temperature is below 50°C, the polymerization reaction will not proceed sufficiently, resulting in low productivity;
If the temperature exceeds 0°C, it becomes necessary to adjust the intrinsic viscosity [η] of the resulting polymer, making it impossible to obtain an ethylene polymer or copolymer with desired properties. In addition, in this step (a), α-olefins other than ethylene, such as propylene, butene-1 + pentene-1, hexene-1s, etc.
n is 0.5% by weight or less, and the intrinsic viscosity [η] is 11
The yarn fl is set to produce ~26 d//i of ethylene polymer or copolymer, preferably 12-24 d//i. To achieve these conditions, in addition to the above temperatures, pressure and ethylene supply grade are required.

The supply of other α-olefins, the amount of hydrogen supplied, etc. may be appropriately selected. In particular, the limiting viscosity [η] can be adjusted using molecules such as hydrogen bt K+! 71 can be easily achieved by using a softening agent. In the ethylene polymer or copolymer obtained in this (FL) step, other α-A
If the fin content exceeds 0.5% by weight, it becomes necessary to reduce the polymerization amount by 1%, leading to a decrease in productivity. When the intrinsic viscosity [η] is less than 11 dl/y-, the final result is 11)
The swell ratio of the ethylene polymer or copolymer becomes small and unsuitable for blow molding;
Exceeding l/f will make continuous operation difficult and damage the product.
f5. Since skin occurs, it cannot be used for practical purposes. Sara K
In step (a), 3 of (a), (b), and (c)
5-23% of the total polymerization amount of the process, or 8-2%
It is necessary to adjust the polymerization amount within the range of 0% by weight, preferably 10 to 17% by weight. This is carried out by appropriately selecting the polymerization time depending on the polymerization conditions.

If the polymerization amount is less than 1% of the total polymerization, the swell ratio of the final ethylene polymer or copolymer will decrease, and at the same time the compatibility of the polymers or copolymers produced in each step will decrease. Further, the bulk density of the produced polymer becomes low, causing problems such as continuous operation becoming impossible. Moreover, if it exceeds 23% by weight, moldability deteriorates, which is not preferable.

In the method of the present invention, after the above-mentioned step (a) is completed, steps (b) and (0) are performed in any order. In other words, in the method of the present invention, the polymerization reaction is carried out in the order of (a) step → (b) step → (c) step, or in the order of (a) step → (c) step → (b) step. Here, step (b) is carried out at <7 (1 to 100°C, preferably 75°C) as described above.
Polymerization is carried out at a temperature of ~95°C.

T1 of this step (b). If the heating temperature exceeds 100°C, part of the polymer will dissolve in R1 Since it becomes a δ falcon state, ii' = #'', 1 tefi 1 rotation becomes 1 filF.In addition, in this step (b), in addition to the above-mentioned temperature conditions, the properties of the ethylene polymer or copolymer to be embroidered are That is, in step (h), the content of other α-olefins in ethylene is 0.5% or less, and the intrinsic viscosity [η] is 0.25.
~i, 6g7/y, preferably 0.3-1.4dl/7
The conditions for producing the ethylene polymer or copolymer are set. Here, jft containing other olefins is 0.5
If the amount exceeds % by weight, the solvent-soluble components of the resulting ethylene polymer or copolymer will increase, which is undesirable. Furthermore, under conditions where the intrinsic viscosity [η] is less than 0.25 d//f/, the solvent-soluble components of the resulting ethylene polymer or copolymer increase, while under conditions where the intrinsic viscosity [η] is greater than 1.6 J/y. , the fluidity and environmental stress cracking resistance (B5OR) of the ethylene polymer or copolymer are reduced, making it impractical. Note that these conditions merely set the properties of the ethylene polymer or copolymer produced when unreacted ethylene monomer or other α-olefin monomer is supplied to step (b) and polymerized. , a mixture (monomer) containing a polymer that has been polymerized to some extent through step (a) or further step (C).

mixture of oligomers, polymers, copolymers) (b)
It does not set the properties of the ethylene polymer or copolymer produced when introduced into the process.

This also applies to step (C). Therefore,
The conditions in step (b) can be independently and easily set without being influenced by the conditions in step (a) or the properties of the produced polymer. In other words, (b)
The polymerization conditions in the step (the same applies to step (C)) are determined based on the properties of the polymer and copolymer produced from the monomer raw materials, and are different from those actually produced in step (b). , it does not specify the properties of the copolymer. Therefore, (b
The conditions for the step (a) or (c) can be set in advance, regardless of the properties of the polymer produced in the step (a) or (c).

To set the conditions for this (b) process vTI, the reaction pressure, ethylene supply (
+1, water. 1 (This can be easily done by appropriately selecting the supply amount, etc.).

Next, (c) engineering (11! is 60~90″ as already mentioned)
c1 The polymerization is preferably carried out at a temperature of 65 to 85°C. If the temperature in this step (c) is less than 60'C, the Shinsuke warehouse temperature is ifV! <Productivity decreases, and if the temperature exceeds 90"C, part of the polymer melts and becomes agglomerated, making continuous operation difficult. In addition, in this step (c), the α-olefin supplied with ethylene is The content is 2 to 15 ht%,
Preferably 4 to 10% by weight, with a limit of 1ir;
v) F2.9~5-1 dl/F! ,, like t t
, <+; Conditions are set so as to produce an ethylene polymer or copolymer of 45.1 to 4.7α/1.

Such condition settings include pressure, ethylene supply amount, and other α-olefin supply I11. as in the case of steps (a) and (b). It is sufficient to appropriately select the hydrogen supply barrier and the like. In addition, the condition settings for this step (c) are as follows: (b)
) As in the case of step (a) or further (
It is not based on the properties of the polymer or copolymer itself that is actually produced in step (c) using a mixture containing polymers, etc. that have undergone step b) as a raw material.

The conditions for the ethyl-[mu] aggregate to be produced in step (Q) above are such that the content of other α-olefins (e.g. propylene, butene-1, pen'tene-1, hexene-1, etc.) is %, the ESC! of the final ethylene polymer or copolymer obtained. R decreases, reverse Kso weight h
If it exceeds t%, the rigidity decreases, which is not preferable. Furthermore, under conditions where the intrinsic viscosity [η] is less than 2.9 dl/f/, the B5OR of the ethylene polymer or copolymer obtained as a product decreases, while when it exceeds 5.1 J/FF, the fluidity decreases. and becomes of low practical value.

In the method of the present invention, either step (b) or step (c) described above may be performed first, but in either case, (
The ratio of polymerization amount in step 1,) and step (c) is calculated as (
b) Step: (C) Step = 1: Polymerization should be carried out while adjusting the ratio in the range of 0.5 to 1.5, preferably 1:0.6 to 1.3. If the polymerization in steps (b) and (e) is carried out at a polymerization ratio outside this range, the compatibility of the polymer or copolymer produced in each step will deteriorate, and the resin pressure will increase, which is undesirable.

The polymerization method in each step of the method of the present invention is
J-polymerization, solution polymerization, gas phase polymerization, etc. are all possible, and both type and batch type are possible. Example 4,
t', 5-stage grinding fR combination is carried out, if the solvent is pentane, n-benzene, cyclohexene, heptane,
Inert solvents such as benzene and toluene can be used.

The method of the present invention has three stages as described above! By carrying out the polymerization of 1 to 1, the intrinsic viscosity [η] is 2.5 to 5. 'ldl/
7, preferably 3.0 to 4.5 dl/f/-, and an ethylene polymer or Production of a copolymer.This ethylene polymer or copolymer has an intrinsic viscosity [η] of 2.5 to 5.2.
Since it is in the ctl/f range, the melt tension is sufficient (301 or more) and the moldability is also good. Also, the density is 0.
Since it is within the range of 939 to 0.965 P/cd, mechanical strength such as rigidity (Olzen stiffness 7000 kg/c1
1 or higher) are also excellent. Particularly in blow molding, the melt tension is high, parison breakage can be prevented, the swell ratio is high at 1.4 or more, and the dependence of the swell ratio on the shear rate is small, so the molding tolerance is wide. Furthermore, in inflation molding, the film has excellent bubble stability, good film appearance, and low resin pressure, resulting in excellent moldability. Furthermore, it has an excellent KSOR of 200 hours or more, and has a low solvent-soluble component of 5% or less. Therefore, the ethylene polymer or copolymer obtained according to the present invention can be widely and effectively used. Furthermore, the method of the present invention has the advantage of eliminating the need for a degassing tank because the polymerization proceeds in step (a), which is the first stage of polymerization, under conditions with less hydrogen supply.

Therefore, according to the method of the present invention, an ethylene polymer or copolymer with excellent properties can be efficiently produced, and it is an extremely valuable method from an industrial perspective.

Next, the present invention will be explained in more detail using examples.

Example 1”111-5 and Comparative Examples 1-10 (1) Solid catalyst QI+l; 1L1! of components n-hebutane 50m/
Magnesium jetoxide inside 1. of f (8,8 mi!J%le) and heavy f1! (1.067- (8.8 mmol) of magnesium sulfate) was completely suspended, and then 1.57 (8.8 mmol) of silicon tetrachloride and 1.6 (35.2 mmol) of ethanol were added and heated to 80°C. The reaction was carried out for 1 hour.Then, 51 nl of titanium tetrachloride (
45 mmol) and reacted at 98°C for 6 hours.

After the reaction, the mixture was cooled down and the liquid was removed by a decanting method.

Next, 100 Il of n-hebutane was newly added, stirred, and left to stand.

After performing a washing operation to remove the supernatant liquid three times, 200 r+l of n-heptane was added to obtain a dispersion of the solid catalyst component.

As a result of determining the amount of titanium supported on this material using a colorimetric method, it was found that 4
2 pg-T1/ff-carrier.

(2) Production of ethylene copolymer A 21-volume stainless steel autoclave was purged with dry nitrogen, and then 0.5ts of dry hexane was added to the solid catalyst component produced in (1) above. J moles (titanium concentration 0.
16 mmol/l), hethylaluminum 0.21
mmol and diethyl aluminum chloride to 0.
59 mmol was added.

Then, the ethylene polymer has an intrinsic viscosity (V) shown in Table 1.
The hydrogen and reactor total pressure were metered so that 8.
Ethylene was continuously supplied so that the ratio was 7k17/C11G, and the reaction was carried out at the predetermined temperature shown in Table 1 for 25 minutes with stirring.

Next, in the second stage, after cooling the reactor to 40°C, ethylene, propylene and the intrinsic viscosity [η] shown in Table 1 were added.
Add hydrogen measured to give a total pressure of 8.5 ky/
cd G, the reaction was carried out with stirring for 120 minutes at the specified temperature shown in Table 1.1 In the sixth step, 0.51 g of dry hexane was added, and ethylene, propylene, butene-1 and Table 1 were added. Add hydrogen measured to achieve the limiting viscosity shown, and increase the total pressure to 6 kl? /criI, and the reaction was carried out at the prescribed temperature shown in Table 1 for 30 minutes with stirring.

After the end of anti-bIS? 1) The obtained ethylene copolymer composition was washed and dried (12), and its physical properties were measured. The results are shown in Tables 1 and 2.

Example 6 (1) Production of catalyst 5605 g of aluminum chloride per 50 m of ethanol (!
J8 mmol) and magnesium jetoxide 1o1
7 (88 mmol) was added. This reaction caused an exotherm of l-1 and a 7·T1 stream of ethanol.

5.12 (Vacuum drying for 6 hours in BiC, I, Y, l
, J. 11) The resulting solid was ground in a ball mill for 60 minutes at room temperature. Next, this powdered solid 17- was filtered with n-heptane and filtered with 3 ml of titanium tetrachloride.
was added and reacted at 100°C for 3 hours. After reaction, n-
Washing with 5Qm/heptane was repeated three times, and after washing, 200 ml of n-hebutane was added to form a suspended catalyst component. The amount of titanium supported by this product is 5 Q 1!9
It was a Ti/f-carrier.

(2) Production of ethylene copolymer In (2) of Examples 1 to 5, the above (
Examples 1 to 5 (except that the catalyst obtained in 1) was used
The same procedure as 2) was carried out. The results are shown in Tables 1 and 2.

Example (1) Preparation of catalyst 10.07 (88 mmol) of magnesium jetoxide was dispersed in 150% n-heptane, and 1% of silicon tetrachloride was dispersed.
．． 09y (11 mmol) and Impropatool 1.
52f/- (22 mmol) was added at room temperature, the temperature was raised to 80°C, and the reaction was carried out for 2 hours. Next, 25 ml of titanium tetrachloride was added to this dispersion, and the reaction was further carried out at about 100°C for 3 hours. After cooling, free chlorine ions were detected, and the suspension was washed with n-hebutane, and the final (τ2) normal hebukun was added to prepare the catalyst component (A), p77F, l solution.This suspension The amount of solid components inside is 78 vg-Ti/f/
- It was a carrier.

(′λ) Ejiren co! P+ of R combination! Wait/r+'
+i f"I'~5(2), 41.1; Proceed in the same manner as 'P: ft111~5(2), except for using (1) as a component in (1) above. Natsu/to.The results are shown in Tables 1 and 2.

2 Table-1... AST) A Based on D747-2... Toyo fi! f es (/n3 II melt tension tester used, orifice D=2.10m1m, L==
8.00 m/7? ! , temperature 190°C,
Measured values under conditions of plunger descending speed 150/min and thread take-up speed 10/min.

Middle 3... Using gear pillar rheometer, orifice D = 0.06 inches, L = 2 inches, temperature 190°C
, a shear rate of 10.55 ec-', a strand of 5 cnI was naturally air-cooled, and the sample diameter/nozzle diameter was calculated.

・4...3m, measured by Be1l method using 10% Nissan Nonion aqueous solution.

Fist 6... Zamble 10f using Soxhlet extraction method!
was extracted with 100 mg of Hegisan for 6 hours.

Patent issued by M'1 person Patent attorney Kubota Fujibe, agent for Idemitsu Petrochemical Co., Ltd. (spontaneous) 9116/1980 Commissioner of the Japan Patent Office Manabu Shiga 1, Indication of the case Patent application 102856/1982 2, Name of the invention Process for producing ethylene polymers or copolymers 3, relationship with the amended case Patent applicant Idemitsu Petrochemical Co., Ltd. 4 Published by agent 04 1-1-1 Kyobashi, Chuo-ku, Tokyo (No. 1 West) Kan Building 5th Floor (7407) Patent Attorney Kubo IJI Fujibe Telephone (27)
5) No. 0721 No. 5, Detailed Description of the Invention of the Specification Subject to Amendment 6, Contents of Amendment (1) Specification p) Page 10 "[Temperature Article (
'1' should be between 150 and 80°C. ]
[Usually 40°C or higher, preferably] is added between the two.

(2) In the same No. 10ri, in the second line from the bottom, change "less than 50°C" by 4 to "less than 1-40°C."

(hereinafter “2”)

Claims (1)

[Claims] +1) Ethylene polymer or copolymer produced by three-step polymerization using (A) a solid catalyst component containing at least titanium, magnesium and halogen and (B) a catalyst whose main component is an organoaluminum compound. In the method of FJM, as the first step, (a) step: temperature 50~
At 80°C, the content of other α-olefins is 0.5
A step of producing an ethylene polymer or copolymer having a weight M% or more and an intrinsic viscosity [η] of 11 to 26 dl/f at a proportion of 5 to 23 weight % of the total polymerization H, followed by Step (b): At a temperature of 70 to 100°C, other α-
Step of producing an ethylene polymer or copolymer having an olefin-containing carp content of 0.5% by weight or less and an intrinsic viscosity [η] of 0.25 to 1.6 dl/7 and (C) step: Temperature At 60 to 90°C, the content of other α-olefins is 2 to 30% by weight, and the intrinsic viscosity [η] is 2.9 to 5.1 dl/
The two steps of producing the ethylene copolymer 9- are performed in any order, and the ratio of polymerization amounts in step (b) and step (C) is (b) step: (C) step N = 1: Intrinsic viscosity [η] 2.5-5.2 #/7° Density 0
．． A method for producing an ethylene polymer or copolymer having a molecular weight of 939 to 0.965 f-/ad.