JPS6019925B2 - Manufacturing method of polyethylene powder - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing polyethylene powder with good powder properties.

More specifically, the present invention relates to a method for producing polyethylene powder using a novel catalyst formed by reacting a group inorganic oxide, a special organomagnesium compound, and a titanium compound and/or vanadium. Gas phase polymerization and suspension polymerization are already known as general polymerization methods for ethylene.

On the other hand, ethylene polymers are generally used in the form of pellets, which requires extra energy to form into pellets using an extruder. Since the polymer in gas phase polymerization and suspension polymerization is in powder form, it is extremely advantageous in terms of effective energy utilization if it can be used as is.
However, to achieve this, it is necessary to obtain a powder with high bulk density and uniform particle size. Furthermore, a good polymer powder can increase the concentration within the IJ actor,
It flourishes in improving productivity. Furthermore, recently there has been an increase in applications requiring polyethylene powder, such as rotational molding, electrostatic coating, and Akatsuki molding.

In these applications, powders that not only have good powder properties but also control bulk density, grain size, etc. are required depending on the application. In order to obtain these various powders, polyethylene powder or pellets are generally crushed and separated, but this method requires extra cost and, in addition, generates whisker-like polymers and residual polymer. There are many problems. Therefore, the most desirable method is to use a specific catalyst to produce polyethylene powder with controlled powder properties through polymerization. For example, British Patent No. 960232 discloses a method for controlling the powder properties of polyethylene powder using a catalyst.

However, this catalyst has the disadvantage of low activity and the need for removal of catalyst residue. Having a catalyst activity high enough to eliminate the catalyst residue removal step is a necessary condition from the viewpoint of cost reduction, and a technology that can control powder characteristics with a highly active catalyst is desired. As a catalyst showing high activity,
A method using a reaction product of a titanium compound and/or a vanadium compound and an organomagnesium compound soluble in a hydrocarbon solvent is disclosed in Japanese Patent Publication No. 52-367 and Japanese Patent Publication No. 52-36.
No. 79, Hakamako Sho 52-36791, Tokuko Sho 52-3
6795, Japanese Patent Publication No. 52-36796, etc.

The present inventors improved the technology of using a reaction product of a titanium compound and/or a vanadium compound and an organomagnesium compound soluble in a hydrocarbon solvent as a catalyst, and produced a highly active polyethylene powder with good powder properties. As a result of extensive research into methods for doing this, we have arrived at the present invention.

That is, the present invention provides ethylene or ethylene and other Q
- In producing polyethylene powder by polymerization or copolymerization of olefins, as a catalyst, [A] (i) in the presence of a solid inorganic oxide, (ii) with the general formula MOM-D
r (wherein M is a metal atom of Group 1 to Group m of the periodic table, Q
, p, q, r are 0 or a number greater than 0, p1q=mQ+
2, 0≦q/(Q+1)<2, where m is the valence of M, RI is one type or a mixture of two or more of solid hydrocarbon groups having 1 to 2 carbon atoms, and × is hydrogen atom or oxygen,
One type or a mixture of two or more types of negative groups containing nitrogen or sulfur atoms, and D represents an electron-donating organic compound. ) is an organic magnet that is soluble in hydrocarbon solvents. This invention relates to a method for producing polyethylene powder using a solid catalyst obtained by reacting a ium compound with (iii) a titanium compound and/or a vanadium compound, and an organometallic compound (B).The present invention will be described in detail below.

The first feature of the present invention is that ethylene or ethylene and other Q-olefins are polymerized or copolymerized by a gas phase method or a suspension method to obtain a polymer with a density of 0.975 to 0.910.
It is possible to produce polyethylene powder having good powder properties.

The powder according to the present invention can achieve a bulk density of 0.3 chicks/clump or more as shown in the examples below, and can be rotomolded,
Suitable for molding methods such as fluid immersion.

The second feature is that polyethylene powder with uniform particle size can be produced. The third feature is that it is possible to produce polyethylene powders ranging from polyethylene powders with a narrow molecular weight distribution of FR40 or less to polyethylene powders with a relatively wide molecular weight distribution of FR50 or more. The fourth feature is that since the catalyst used in the present invention has high catalytic activity, there is little catalyst component remaining in the polymer, and the step of removing the catalyst remaining groove can be omitted. As the polymerization method used in the present invention, either gas phase polymerization or suspension polymerization in the presence of a solvent can be employed.

In gas phase polymerization, in order to achieve good contact between the Q-olefin and the catalyst, methods such as mixing using a fluidized bed, moving bed, or takazusa machine are used, and 30q to 120 qo is mixed at a pressure of 1 to 50 kg/h. Polymerization can be carried out under temperature conditions.
Suspension polymerization uses polymerization solvents such as propane, butane, isobutane, bentane, isobentane, hexanehef. A catalyst is introduced into the reactor, and the Q-olefin is reacted under an inert atmosphere. The polymerization can be carried out at a temperature of 30° C. to 110 qo by pressurizing 1 to 50 k9/carp. The polymerization may be carried out in a single-stage polymerization using one reaction zone, or it is also possible to carry out a so-called multi-stage polymerization using a plurality of reaction zones.

Although this polymerization method produces polymers with narrow to wide molecular weight distributions in one stage polymerization, it is also possible to produce polymers with wider molecular weight distributions by multistage polymerization. To control the density of polyethylene, propylene, 1-butene, 1-octene, 1-bentene, 1-hexene, 1
-heptene, 1-octene, 1-nonene, 1-decene,
1-dodecene, 1-tetradecene, 1-octadecene,
Copolymerization can be carried out by adding 4-methyl-1-pentene or the like. In addition, in order to control the molecular weight,
It is also possible to change the temperature of the reactor or to add hydrogen, organic compounds susceptible to chain transfer. Examples of the solid inorganic oxide used in the catalyst of the present invention include silica, alumina, silica alumina, magnesia, thoria, zirconia, or a mixture of two or more thereof.

In particular silica or silica alumina is used. (i
) The specific surface area of the solid inorganic oxide is preferably 20〆/g
In view of the above, it is further recommended that the particle size is 2/ta of 100 or more, and the particle size is 0.01 to 500, preferably 0.1 to 100.

(i) The solid inorganic oxide is heated at 20,000 to 1,200 q○ under an inert gas stream or under reduced pressure, preferably from 300°C to 90°C.
Use after drying at 0oo provides stable reproducibility and is recommended. Next, (ii) general formula MQMgR1pXq
The organomagnesium compound represented by Dr (wherein M, R1, However, it includes all dihydrocarbylmagnesium and rust forms of these and other metal compounds.

In the above formula, M can be a metal element belonging to Group 1 to Group M of the periodic table, such as lithium, sodium, potassium, beryllium, calcium, strontium, barium, zinc, boric acid, aluminum, etc. In particular, lithium, beryllium, zinc, boric acid, and aluminum are preferred.

More preferably, aluminum is used. The ratio Q' of metal atoms M to magnesium atoms is 0 or a number greater than or equal to 0, preferably OSQSI. 0 especially OSQSO
．． 5 power is recommended. The hydrocarbon group represented by RI is
One or a mixture of two or more hard alkyl groups, cycloalkyl groups, or allyl groups having 1 to 2 carbon atoms, such as methyl, ethyl, propyl, butyl, amyl, hexyl, heptyl, octyl, nonyl, decyl,
Examples include cyclohexyl, phenyl, and benzyl groups. Particularly preferred are alkyl groups. X represents one type or a mixture of two or more types of a hydrogen atom or a negative group containing an oxygen, nitrogen or sulfur atom.

Preferably, OR2, OSiR3R4R5, NR6R7, SR8, (wherein R2 to RII represent a hydrocarbon group having 1 to 20 carbon atoms, and R3 to R7 and R10 may be a hydrogen atom.

) are used, and more preferably alkoxy groups (OR2) and siloxy groups (OSiR3R4R5) are recommended. Relational expression of symbols Q, p, q p+q=mQ+2
indicates the stoichiometry between the valence of the metal atom and the substituent, and the preferred range of 0≦q/(Q+1)<2 means that x is 0 or more and less than 2 for the sum of metal atoms. shows.

Preferably 0≦q/(Q+1)1. is more preferably used in the range of 0≦q/(Q+1)≦1. The organomagnesium compound used in the present invention needs to be soluble in a hydrocarbon solvent in order to obtain a good powder.
Generally, organomagnesiums with Q=0 are insoluble in hydrocarbon solvents.

However, a special organomagnesium compound, CH3Mg (
n-C3 day 7). CH3Mg (i-C3 day 7), C2 day 2Mg (i-C3 day 7), n-C3 day 7Mg (j-C3 day 7)
Day 7), n-C4 day 7), n-C4 day 9Mg (secC4 day 9), C2 day 5Mg (n-C4), etc. are soluble in hydrocarbon solvents, and these The compounds are preferably used in the present invention. As the electron-donating compound represented by ○, an electron-donating organic compound containing oxygen, nitrogen, sulfur, or phosphorus atoms is used.

These compounds include ethers such as diethyl ether, dibutyl ether, diisoamide ether, ethylene glycodimethyl ether, diethylene glycol dimethyl ether, glycerin trimethyl ether, vinyl methyl ether, tetrahydrofuran, dioxane, crown ether, propylene oxide, and hexamethyl dimethyl ether. Siloxane, siloxanes such as symmetrical dihydrotetramethyldisiloxane, bentamethyltrihydrotrisiloxane, cyclic methylhydrotetrasiloxane, methylhydropolysiloxane, dimethylpolysiloxane, phenylhydropolysiloxane, triethylamine, tributylamine, tetramethylethylenediamine, Tertiary amines such as bis(dimethylamino)methane and diazabicyclooctane; nitriles such as acetonitrile, propionitrile, acrylonitrile, penzylnitrile, and benzonitrile; amides such as dimethylformamide and hexamethylphosphoramide; Pyridine derivatives such as pyridine and methylpyridine, thioethers such as diethyl sulfide, ethylpropylsulfide, propyl sulfide, and ethylene sulfide, sulfoxides such as dimethyl sulfoxide, diethyl sulfoxide, and dibutyl sulfoxide, and triethylphosphine. , phosphines such as triphenylphosphine. Preferably ethers, siloxanes or amines are used. r represents the amount of the electron-donating organic compound D coordinated to M or Mg, and 0
or a number greater than 0, preferably 10 or less, more preferably 2 or less.

These magnesium compounds have the general formula RIMgY, R Mg (Y is a halogen atom, and RI has the above-mentioned meaning.

) or a mixture thereof, and the general formula MR point, MRXbYc, Mold; Dr, MRsa×bY
an organometallic compound represented by cDr (wherein M, R1, in an inert hydrocarbon such as hexane, heptane, octane, cyclohexane, benzene, toluene, etc.
to 150 pm, and if necessary, subsequently reacted with an electron-donating compound or alcohol, siloxane, amine, imine, thiol or dithio compound. Next, (iiD titanium compounds and/or vanadium compounds include titanium tetrachloride, titanium tetrabromide, titanium tetraiodide, ethoxytitanium trichloride, propoxytitanium trichloride, butoxytitanium trichloride, octoxytitanium trichloride, Diethoxytitanium dichloride, dipropoxytitanium dichloride, dibutoxytitanium dichloride, triethoxytitanium dichloride, tripropoxytitanium chloride, tributoxytitanium chloride, phenoxytitanium trichloride, benzoyltitanium trichloride, dicyclobentadienyl titasodichloride, Tetraisopropoxytitanium, tetrabutoxytitanium, vanadium tetrachloride, vanadyl trichloride, ethoxyvanadyl dichloride, propoxyvanadyl dichloride, butoxyvanadyl dichloride, diethoxyvanadyl chloride, diproboxyvanadyl chloride, dibutoxyvanadyl chloride, tributoxyvanadyl, etc. Titanium and vanadium halides, oxyhalides, alkoxyhalides, alkoxides, etc. may be used alone or in mixtures.Titanium or vanadium compounds containing at least two chlorine atoms are preferred, and titanium tetrachloride is more preferred. ,
Vanadium tetrachloride and vanadyl trichloride are used. component【
For the reactions i), (ii), and [iii), it is necessary to simultaneously introduce components (ii) and (iii) into the hydrocarbon solvent slurry of component (i) and carry out the reaction.

The reaction is preferably carried out in the presence of a hydrocarbon solvent.

As the hydrocarbon solvent, aliphatic hydrocarbons such as hexane, heptane, and octane, aromatic hydrocarbons such as benzene and toluene, and alicyclic hydrocarbons such as cyclohexane and methylcyclohexane are used. The amounts of components (i, (ii), (iii)) used in the reaction are not critical.

Preferably component (ii) 0.0 to component (i) ig
8 hmol to 10 hmol, component (iii) 0.
05 hmol to 10 hmol, particularly preferably 0.3 mmol to 5 melon hmol of component (ii) per 1 g of component (i), 0.3 hmol to 5 melon hm of component blood.
Used in the range of ol. For the number of moles of component (ii), a value calculated as the sum of metal atoms M and Mg is used. For example, AIMg(C2day5)3(n-C4)2 is 25hol, which corresponds to the molecular weight of this structural formula. The reaction temperature is also not particularly limited, but preferably -30qo to 150o○, particularly preferably -20°C to 135°C.
It will be carried out in [A] The solid catalyst used in the present invention is:
Although it is useful as a catalyst for ethylene polymerization as it is,
[B] A more excellent catalyst can be obtained by combining an organometallic compound.

As organometallic compounds [B], AI (C2 days 5) 3, Yama (C3 days 7) 3, AI (C4 days 9)
3, AI (C5 days,.) 3, AI (C6 days, 3) 3, Yama (C8 days, 7) 3, AI (C, oH illusion) 3 etc. trialkyl aluminum, AI (C2 days, 5) 2 day, N(i-C
4 and 5) Alkylaruminium hydrides such as A
I (C2 day 5) 2CI, AI (C2 day 5) CI2, mountain (
i-C4 day 9) Alkylaluminum halides such as CI2, AI (C2 day 5) 2Br, AI (C2 day 5)
2 (OC2nd 5th), Rainbow (i-C4th day 9) 2 (OC4th day 9)
), alkoxyalkylarminium, mountain (C2 day 5
)2・(OSiHC is C2 day 5), AI(i-C4&)
2.(OSi(C&)2i-C4) is a reaction product of alkyl aluminum such as siloxyalkylaluminum, isoprenylaluminum, myrcenylaluminum, etc. and conjugated diene, Zn(C2day5)2, Zn(C4 Day 9) 2, Zn (C6 day, 3) 2, Zn (C8 day, 7) 2
, Zn (C2 day 5) (n - C3 day 7), Zn (C6 public) 2, Zn (C3 day 7) (OC4 ratio), etc., with the general formula MQMgR1p&Dr (in the formula, M, R1,
, D, Q, p, q, r are as defined above), and mixtures thereof are used.

To achieve high activity, trialkylaluminum is preferred. [A] Solid catalyst and [B] organometallic compound may be added to the polymerization system under polymerization conditions, or may be combined in advance prior to polymerization.

The ratio of the two components to be combined is such that the organometallic compound [B] is 50 hmol to 0.8 hmol, preferably 20 hmol to 1 g of the solid catalyst [A].
It is used in the mmol range. Examples of the present invention are shown below, but the present invention is not limited to these examples in any way.

In these examples, MI stands for melt index, and was measured using ASTM D-12 paper at a temperature of 190 qo.
This was measured under a load of 2.16 kg. F.R.
means the quotient obtained by dividing the value measured at a temperature of 190° C. and a load of 21.6 k9 by the skin, and is one of the measures of molecular weight distribution, and the lower the value, the narrower the molecular weight distribution. The catalytic activity is
It is expressed as the amount of polymer produced in grams per gram of solid catalyst per hour. The component (l) used in each example was
After drying at 50 psi for 3 hours, it was used for reaction. Example 1 Oxygen and moisture inside a 300' flask equipped with two dropping funnels were removed by direct nitrogen dusting, and silica (Fuji Davison Chemical, grade 951, average grain size) base was added under a nitrogen atmosphere. I prepared 100 volumes of hexane.

Next, 50' of hexane containing 1410 hmol of TIC and AIMMg(C2&), . 2 (n-C4 day 9). -. (
〇Si/day/CH3/C2 day 5) o. , 1 hmol of hexane was weighed into separate dropping funnels.
Both components were simultaneously added dropwise to the mixture at 5° C. over a period of 1 hour.

The hawk frame was continued for an additional 2 hours at this temperature. The produced solid catalyst was isolated, washed with hexane, and then dried. 1 mg of this solid catalyst and 30.2 hmol of AI (IL-C) were placed in a 1.5-liter autoclave with 800 g of dehydrated and degassed hexane, the interior of which was vacuum degassed and replaced with nitrogen.

Raise the internal temperature of the autoclave to 80℃ and add 1.6% hydrogen.
It was pressurized to a gage pressure of 9 k9/h and then ethylene was introduced to bring the total pressure to 4 k9/h g. The reaction was carried out for 1 hour while maintaining the gauge pressure of 4k9/ground by replenishing ethylene to obtain 14 acid powder. Catalytic activity is 145
00, MI was 6.5, FR was 35, the high density of the powder was 0.4, and the particle size of 35 mesh to 48 mesh was 70 wt% or more. Example 2 Oxygen and moisture inside a 30-piece flask equipped with two dropping funnels were removed by nitrogen substitution, and silica (Fuji Davison Chemical, grade secretion, average particle size 100) was removed under a nitrogen atmosphere. I planted 1 female and 100 hexane.

Next, 50 [and L] of hexane containing 148 mmol of TIC
i. ．． 2Mg(CH3),-. (n-C3 day 7),. .
(〇n1C8th, 7)o. , 50' of hexane containing hmol was weighed into separate dropping funnels. Both components were simultaneously added dropwise to the fly at 10° C. over a period of 1 hour.

The lantern service continued for another hour at this temperature. The produced solid catalyst was isolated, washed with hexane, and then dried. 1 hg of this solid catalyst and 30.2 hmol of AI (i-C4day9) were placed in a 1.5-hg autoclave with 800 g of dehydrated and degassed hexane, the interior of which was vacuum degassed and replaced with nitrogen.

The internal temperature of the autoclave was raised to 80 qo, and hydrogen was added to 1.
It was pressurized to 6k9/kg gauge pressure and then ethylene was introduced to bring the total pressure to 4k9/kg gauge pressure. By replenishing ethylene, the reaction was carried out for 1 hour while maintaining a gauge pressure of 4k9/m, yielding 11 rudders of powder. Catalyst activity is 11500. The plate size was 2.6, the FR was 36, the bulk density of the powder was 0.41 g/ground, and the particle size of 20 mesh to 28 mesh was 55 wt% or more. Example 3 2 g of solid catalyst synthesized in Example 1 and 2 g of AI (C2 ratio)
C.I.O. The interior of the autoclave was vacuum degassed, and 4 mmol was added to 800 g of dehydrated and degassed isobutane.

After introducing 85' of 1-octene into the autoclave and raising the temperature of the autoclave to 80°C, hydrogen was added to 1.5
The mixture was pressurized at a pressure of 9 kg/kg, then ethylene was introduced, and polymerization was carried out for 1 hour while maintaining the total pressure at a gauge pressure of 15 kg/kg.
No. 21 powder was obtained. Catalyst activity is 10750, M12.
2, FR29, density 0.924, the high density of the powder was 0.4 base/base, and the particle size of 35 mesh to 48 mesh was 65 M%. Example 4 Oxygen and moisture inside a 300' flask equipped with two dropping funnels were removed by nitrogen substitution, and magnesium oxide (Kyowa Kagaku, Kyowa Mag 150) was removed under nitrogen atmosphere.
) I made sure to add 120 parts of hexane.

Next, 30' of hexane containing TIC13 (0n-C4day9) 1 mol and Mg (n-C4day9) sail (sec-C
4th 9) o. 9(OSi(CH3)3)o. 213hm
30' of hexane containing ol was weighed into a separate addition funnel. Both components were simultaneously added dropwise to the pork azusa at 120° C. over a period of 2 hours. Furthermore, at 50 pm, the lantern worship continued for two hours. The produced solid catalyst was isolated, washed with hexane, and then dried. 2 hg of this solid catalyst and 0.4 mmol of N (C2 5) 2 (OSiH C2 C2) were dehydrated and degassed in hexane 80
1.5 where the inside was vacuum degassed and replaced with nitrogen.
I put it in an autocrepe.

Raise the internal temperature of the autoclave to 8-0, and hydrogen to 1.6
It was pressurized to a gauge pressure of 9 k9/m and then ethylene was introduced to bring the total pressure to 4 k9/m gauge. 1 while maintaining the gauge pressure of 4 kg/ground by replenishing ethylene.
The reaction was carried out for a period of time, and 13 crab powders were obtained. Catalytic activity is 69
00. My skin is 8. The FR is 42 and the bulk density of the powder is 0.
．． Those with particle size of 145 mesh to 280 mesh had a fear of 7% or more. Example 5 Oxygen and moisture inside a 300' flask equipped with two dropping funnels were removed by nitrogen substitution, and 1 volume of silica (Fuji Davison Chemical, grade) and 100' of hexane were added under nitrogen atmosphere. I prepared it.

Next, on hexane 10 containing 148 hmol of TIC and N
Mg (C2 France) 2.8 (n-C4 ratio),. 8(N(C2
expansion) 2) o. 44 mmol of hexane was weighed into a separate dropping funnel. Both components were simultaneously added dropwise at −5° C. over a period of 1 minute under a rope. The ritual was continued for 5 hours at this temperature. The produced solid catalyst was isolated, washed with hexane, and then dried. This solid catalyst 2 hg and AIMg (C24
)3(n-C4 is)21. The inside was vacuum degassed together with 800 parts of dehydrated and degassed hexane, and the mixture was placed in a 1.5 quart crepe which was purged with nitrogen.

Claims (1)

[Claims] 1. In producing polyethylene powder by polymerization or copolymerization of ethylene or ethylene and other α-olefins, as a catalyst, [A] (i) in the presence of a solid inorganic oxide; (ii) General formula MαMg^1_pX_q・D_r (wherein, M is a metal atom of Group I to Group III of the periodic table, α, p, q
, r is 0 or a number greater than or equal to 0, p+q=mα+2, 0≦
It has the relationship q/(α+1)<2, where m is the valence of M and R
^1 is one type or a mixture of two or more types of hydrocarbon groups having 1 to 20 carbon atoms, and X is one type or mixture of two or more types of negative groups containing a hydrogen atom or oxygen, nitrogen, or sulfur atom , D represents an electron-donating organic compound. ) A method for producing polyethylene powder using a solid catalyst obtained by reacting an organomagnesium compound soluble in a hydrocarbon solvent with (iii) a titanium compound and/or a vanadium compound, and [B] an organometallic compound. 2. Ethylene or ethylene and other α-olefins in a gas phase at a temperature of 3.
Polymerization was carried out at 0 to 120°C and a pressure of 1 to 50 kg/cm^2, with a density of 0.975 to 0.910 and a bulk density of 0.35.
Claim 1 for producing powder of g/cm^3 or more
The method for producing polyethylene powder described in Section 1. 3 Ethylene or ethylene and other α-olefins are suspended in the presence of an inert hydrocarbon solvent at a temperature of 30°C to 11°C.
Polymerization was carried out at 0°C and a pressure of 1 to 50 kg/cm^2, with a density of 0.975 to 0.910 and a bulk density of 0.35 g/c.
The method for producing polyethylene powder according to claim 1, which produces a powder having a particle diameter of m^3 or more.