GB1588643A – Catalyst for the polymerisation of olefines
– Google Patents
GB1588643A – Catalyst for the polymerisation of olefines
– Google Patents
Catalyst for the polymerisation of olefines
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Publication number
GB1588643A
GB1588643A
GB4205477A
GB4205477A
GB1588643A
GB 1588643 A
GB1588643 A
GB 1588643A
GB 4205477 A
GB4205477 A
GB 4205477A
GB 4205477 A
GB4205477 A
GB 4205477A
GB 1588643 A
GB1588643 A
GB 1588643A
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United Kingdom
Prior art keywords
compound
aluminium
catalyst
group
metal
Prior art date
1977-01-11
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Application number
GB4205477A
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Euteco SpA
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Euteco SpA
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1977-01-11
Filing date
1977-10-10
Publication date
1981-04-29
1977-10-10
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Euteco SpA
1981-04-29
Publication of GB1588643A
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patent/GB1588643A/en
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Classifications
C—CHEMISTRY; METALLURGY
C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
C08F10/00—Homopolymers and copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond
Description
(54) CATALYST FOR THE POLYMERISATION OF OLEFINES
(71) We, EUTECO S.p.A. of Viale Umberto 90, Sassari, Italy, an Italian company, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement:
An object of the present invention is to provide supports particularly suitable for the production of catalysts for the low pressure polymerisation and copolymerisation of a-olefines. In such processes, the catalytic system generally consists of a Ziegler catalyst, for example a halogen of a transition metal and an organic metal compound.
The transition metal may notably be fixed onto a support such as Awl203, aluminium silicates, SiO2, MgO, MgC03 or Mg(OH)2.
Said low pressure polymerisation processes may also be executed in the presence of catalytic complexes of the Tics. 1/3 AIC13 type, as described in British patent 1,268,415, and in U.S.A. patent 3,639,377.
Processes of this type have the advantage of easy control of the average molecular weight of the product polymers. However, they have a considerable drawback in that the polymers generally require washing with alcoholic solutions to separate them from the harmful residues of the catalytic system.
Halogenation of the supports, for example Awl203, SiO2, MgO or SiO2.Al203, lead to a considerable increase in the activity of the catalyst system, such that it is possible to avoid the costly final wash of the polymer (see for example, British patents 1,314,784, and 1,315,770).
Such catalysts however do not allow easy control of the average molecular weight of the polymer, and the products are therefore often difficult to work, having, in general, very high average molecular weights and melt indices approximately equal to zero (measured by the
ASTM D 1238 method, with a weight of 2.16 Kg).
We have now discovered a process for the polymerisation and copolymerisation of aolefines, which combines the advantages of both the aforementioned types of catalyst, i.e.: a) high catalytic activity in polymerisation such that it is possible to dispense with any washing of the polymers obtained:
b) easy control of the average molecular weights of the polymers.
I ne invention therefore consists in a catalyst for the homo or copolymerization of olefins, obtained by reacting an organometal compound of a metal of Group I, II or III of the periodic table with the product of the reaction between a compound of a group IV to group VI metal and a support consisting of a partially hydrolysed aluminium compound, of the formula (I)
AIF (3-n).nOH (I) where:
n is a number of at least 0.01 and less than 3, and preferably at least 0.05.
The invention also consists in a process for the homo or copolymerization of olefins containing 2 to 10 carbon atoms, in accordance with the low pressure Zeigler method, in the presence of a catalyst of the invention. The support is preferably obtained by partial hydrolysis at a temperature of from 100 to 8000C for from 1 to 24 hours, preferably with water or aqueous ammonia.
The support may be obtained from the corresponding non-hydroxylated aluminium com pound by subjecting it to partial hydrolysis by the method described in detail below.
Aluminium fluroide exists in three different allotropic forms: a-rhombic, p-hexagonal and y-tetragonal. All three forms are very suitable for the preparation of highly active supports.
However, particularly good results have been obtained from the p-hexagonal form.
The catalytic hydroxylated support is formed by treating an aluminium hydride or an oxygenated inorganic salt of aluminium (such as a sulphate or nitrate) with any compound able to partially hydrolyse it and thus introduce hydroxyl groups therein. Water or aqueous ammonia are preferred for this purpose, but other organic or inorganic substances, either pure or in solution, have been found to give good results.
The reaction between the AIF3 and the compound which is to introduce hydroxyl groups therein may be carried out in a fixed or fluidised bed.
In general, an inert gas is added. Examples include: nitrogen; helium; argon; and air. These gasses may be completely or only partially saturated with the hydrolysing compound. The critical conditions of the partial hydrolysis reaction of the AIF3 are the temperature and duration of treatment. By varying these, the value on n varies in the following manner: as the temperature and duration of treatment increase, n tends to decrease until it virtually reaches zero, although values of n below 0.01 relate to a less satisfactory product.
The range of operating conditions which may be utilised is very wide.
The treatment temperature may vary from 100″ to 800″C, and preferably from 200 to 600″C.
The duration of treatment may vary from 1 to 24 hours and preferably from 4 to 12 hours.
The present invention provides a method for preparing a wide range of catalytic supports for which the specific activity of the final catalytic system, expressed as kg of obtained polymer/g transition metal/hour/atmosphere of olefine, varies as the value of n varies. A simultaneous variation in the properties of the product polymer (such as specific density, crystallinity, average molecular weight and melt index) occurs enabling the preparation of a wide variety of polymers having, for examPle, a specific density which varies from 0.93 to 0.97 and a melt index which can reach 20 (measured by the ASTM D 1238 method, with a weight of 2.16 kg).
The catalytic system according to the present invention is prepared by reacting the hydroxylated aluminium support with a compound of a Group IV to Group VI metal and subsequently activating the catalyst component thus formed by treating it with an organo metal compound of a metal of Group I to Group III of the Periodic Table. The numbers of the groups of the Periodic Table correspond to those of the table given in the «Handbook of
Chemistry and Physics» published by the Chemical Rubber Company.
Heavy metal compounds which are shown to be particularly suitable are halides, oxyhalides and alkoxyhalides.
Preferred metals of Groups IV to VI are titanium, vanadium and chromium.
Suitable compounds are, therefore: Tics, TiBr4, VCl4, VOC13, VOBr3, CrO2Cl2, Ti(O
C2H5)3Cl and Ti(O-isoC4H9)2Cl2. However, best results are obtained with Tics.
The conditions required for the reaction between the hydroxylated aluminium support and the heavy metal compound are not critical, and they may vary over a wide range. The reaction temperature may vary from 0 to 3000C, and the duration of the reaction from 1 to 4 hours.
The heavy metal compound may be used in its pure state or in mixture with an anhydrous organic solvent.
It is preferable to use an excess of groups IV to VI metal compound with respect to the hydroxylated aluminium support.
Examples of organic metal compounds which may be used include: metal alkyls; halides or hydrides of metal alkyls; and Grignard compounds.
Examples of the relative metals are: aluminium; Zn; Mg; Na; and Li. Thus, examples of suitable compounds are: trimethylaluminium; monochlorodiethylaluminium; aluminium diisobutylhydride; (C2H 5) MgBr; and ethylaluminiumsesquichloride.
However, best results are generally obtained with aluminium alkyls or halides of alkyl aluminium. In particular triethylaluminium and triisobutylaluminium are excellent.
The quantity of organic metal compound to be used is not critical. Preferably however, the compound should be present in molar excess with respect to the group IV to VI metal contained in the support.
The catalytic system according to the present invention is applicable to homo or copolymerisation of a-olefines, for example ethylene, propylene, butene.1, pentene.1, hex ene.t and 4-methyl-pentane.l.
It is particularly advantageous when used for the preparation of homo or copolymers of ethylene. The homo or copolymerisation of olefines may be carried out by any of the usual methods, either in the gaseous phase or in solution. In this second case, inert solvents are used, for example, aliphatic or cyclo-aliphatic hydrocarbons.
The average molecular weight of the polymer to be obtained may be controlled either by the choice of the hydroxylated support, prepared in accordance with the invention, or by the addition of one or more molecular- weight regulators, such as hydrogen, alcohols, CO2, Zn alkyls or Cd alkyls.
The density of the product polymers may be controlled by adding to the polymerisation reaction mixture an alkoxide of a metal from Group IV or V of the Periodic Table. Alkoxides of titanium or vanadium, for example Ti (i-butoxy)4 are preferred.
As the melt index of the homo and copolymers obtained by the present invention can vary over a very wide range, these polymers are suitable for many types of operation, such as extrusion or blow moulding.
Some examples are given hereinafter for purposes of illustration. The catalyst supports produced in the Examples illustrating the invention had, of course, compositions within the scope of formula I. All melt index measurements were made in accordance with the ASTM D 1238 method, with a weight of 2.16 Kg.
COMPARATIVE EXAMPLE I
5 g of a-rhombic AIF3 are treated with 75 cc of pure liquid Tics4 and heated under reflux and strong agitation for one hour at a temperature of 136″C. The solid reaction product is separated, washed firstly with TiCl4 and then with anhydrous n-heptane until free chloride has completely disappeared from the wash solvent. It is then dried.
The catalyst component thus prepared has a titanium content of 1.5% by weight with respect to the support.
Polymerisation is then carried out in the following manner:
0.2 g of the catalyst component are added to a solution of 1 g of triethylaluminium in 1500 cc of anhydrous n-heptane. The entire mixture is then transferred under anhydrous nitrogen into a 51 .steel autoclave provided with a bladed stirrer having a stirring speed variable from 500 to 2000 r.p.m. The autoclave is heated to a temperature of 90″C and kept at this temperature during polymerisation (1 hour).
The pressure is raised to 4 Kg/cm with hydrogen and then to 14 Kg/cm2 with ethylene.
During polymerisation, the partial pressure of the ethylene is kept constant by continuously adding new ethylene. After one hour the autoclave is degassed and the product discharged.
The yield is 180 g of polyethylene/g catalyst/h/atmosphere of ethylene.
The specific activity of the catalyst component in terms of the quantity of titanium contained in it is 12.0 kg of polyethylene/g ti/h/atmosphere of ethylene.
The polymer has a melt index of 0.00 g/10 minutes.
EXAMPLE I
5 g of a-rhombic A1F3 are treated in a fluidised bed with nitrogen saturated with 1N aqueous ammonia at a temperature of 200″C for 4 hours.
The compound thus obtained is treated with TiCl4 to prepare the catalyst component, using the same method as described in comparative example 1. The catalyst component thus prepared has a titanium content of 1.8% by weight with respect to the support.
Polymerisation is carried out as described in comparative example 1. The yield is 610 g of polyethylene/g catalyst/h/atmosphere of ethylene.
The specific activity of the catalyst component is 33.88 kg of polyethylene/g Ti/h/atmosphere of ethylene. The polymer has a melt index of 4.0 g/10 minutes.
COMPARATIVE EXAMPLE 2
5 g of p-hexagonal A1F3 are treated with Ti Cl4 prepare the catalyst component using the same method as described in comparative example 1. The catalyst component thus prepared has a titanium content of 0.45% by weight with respect to the support.
Polymerisation is carried out as described in comparative example 1.
The yield is 67 g of polyethylene/g catalyst/h/atmosphere of ethylene.
The specific activity of the catalyst component is 14.88 kg of polyethylene/g Ti/h/atmosphere of ethylene. The polymer has a melt index of 0.1 g/10 minutes.
EXAMPLE2
5 g of p-hexagonal AIF3 are treated in a fluidised bed with helium saturated with water, at a temperature of 500″C for 4 hours.
The compound thus obtained is treated with TiC14 to prepare the catalyst component, using the same method as described in comparative example 1. The catalyst component thus prepared has a titanium content of 0.65 % by weight with respect to the support. Polymerisa tion is carried out as described in comparative example 1.
The yield is 193 g of polyethylene/g catalyst/h/atmosphere of ethylene.
The specific activity of the catalyst component is 29.7 kg of polyethylene/g Ti/h/atmosphere of ethylene. The polymer has a melt index of 2.6 g/10 minutes.
EXAMPLE 3
5 g of p-hexagonal AIF3 are treated in a fluidised bed with helium saturated with water, at a temperature of 300″C for 4 hours.
The compound thus obtained is treated with TiCI4 to prepare the catalyst component, using the same method as described in comparative example 1. The catalyst component thus prepared shows a titanium content of 0.9% by weight with respect to the support.
Polymerisation is carried out as described in comparative example 1, except that instead of using aluminium triethyl, an equal quantity (1 g) of aluminium triisobutyl is used.
The yield is 315 g of polyethylene/g catalyst/h/atmosphere of ethylene.
The specific activity of the catalyst component is 35.0 kg of polyethylene/g Ti/h/atmosphere of ethylene.
The polymer has a melt index of 1.5 g/10 minutes.
EXAMPLE 4
5 g of p-hexagonal AIF3 are treated in a fluidised bed with nitrogen saturated with an aqueous solution containing 3 g equivalent/litre of NH4 OH, at a temperature of 200″C for 4 hours.
The compound thus obtained is treated with TiCl4 to prepare the catalyst component, using the same method as described in comparative example 1. The catalyst thus prepared has a titanium content of 2.5% by weight with respect to the support.
Polymerisation is carried out as described in comparative example 1. The yield is 750 g of polyethylene/ g catalyst/h/atmosphere of ethylene.
The specific activity of the catalyst component is 28.6 kg of polyethylene/g Ti/h/atmosphere o ethylene.
The polymer has a melt index of 2.0 g/10 minutes.
COMPARATIVE EXAMPLE 3
5 g of p-hexagonal AIF3 are treated with 75 cc of pure liquid VOCI3 and refluxed at a temperature of 127″C for one hour with strong agitation. Ths solid reaction product is separated, washed firstly with VOCI3 and then with anhydrous n-heptane until free chloride in the wash solvent completely disappears. It is then dried.
The catalyst component thus prepared has a vanadium content of 1.3% by weight with respect to the support. Polymerisation is carried out as described in comparative example 1.
The yield is 210 g of polyethylene/g catalyst/h/atmosphere of ethylene.
The specific activity of the catalyst component is 16.15 kg of polyethylene/g vanadium/h/atmosphere of ethylene. The polymer has a melt index of 0.2 g/10 minutes.
EXAMPLE 5
5 g of p-hexagonal AIF3 are treated in a fluidised bed with helium saturated with water, at a temperature of 300″C for 4 hours.
The compound thus obtained is treated with VOCI3 to prepare the catalyst component, using the same method as described in comparative example 3. The catalyst component thus prepared has a vanadium content of 2.7% by weight with respect to the support.
Polymerisation is carried out as described in comparative example 1.
The yield is 760 g of polyethylene/g catalyst/h/atmosphere of ethylene.
The specific activity of the catalyst component is 28.1 kg of polyethylene/g vanadium/h/atmosphere of ethylene. The polymer has a melt index of 1.4 g/ 10 minutes.
COMPARATIVE EXAMPLE 4
5 g of Al2 (SO4)3 are treated in a fluidised bed with nitrogen containing water vapour, at a temperature of 200″C for 6 hours.
The compound thus obtained is treated with TiC14 to prepare the catalyst component, using the same method as described comparative example 1. The catalyst component thus prepared has a titanium content of 0.55% by weight with respect to the support.
Polymerisation is carried out as described in comparative example 1.
The yield is 139 g of polyethylene/g catalyst/h/atmosphere of ethylene.
The specific activity of the catalyst component is 25.3 kg of polyethylene/ Ti/h/atmosphere of ethylene.
The polymer has a melt index of 0.5 g/10 minutes.
WHAT WE CLAIM IS
1. A catalyst for the homo or copolymerisation of olefines, obtained by reacting an organo metal compound of a metal of Group I, II OR III of the Periodic Table with the product of the reaction between a compound of a Group IV to Group VI metal and a support consisting of a partially hydrolysed aluminium compound, of the formula (I)
(I)
AIF (3-n) .nOH where:
n is a number of at least 0.01 and less than 3.
2. A catalyst according to claim 1, in which n is at least 0.05.
3. A catalyst according to Claim 1 or Claim 2, obtained by a process substantially as described in any one of Examples 1 to 6.
4. A process for the homo or copolymerisation of olefines containing 2 to 10 carbon atoms in accordance with the low pressure Ziegler method, in the presence of a catalyst according to Claim 1, Claim 2 or Claim 3.
5. A process as claimed in Claim 4, wherein the support as defined by the aforesaid formula (I) is obtained from a corresponding non-hydroxylated aluminium compound by treatment at a temperature of from 100 to 8000C for from 1 to 24 hours with water or aqueous ammonia or another inorganic substance or an organic substance either pure or in solution, suitable for introducing hydroxyl groups into the non-hydroxylated aluminium compound.
6. A process as claimed in Claim 4 or Claim 5, wherein aluminium fluoride is present in any one or more of its three allotropic forms, namely a-rhombic, p-hexagonal or y-tetragonal.
7. A process as claimed in any of the preceding claims, wherein said Group IV, V or VI metal is titanium, vanadium or chromium.
8. A process as claimed in any of the preceding claims, wherein said compound of a
Group IV, V or VI metal is a halide, oxyhalide or alkoxyhalide.
9. A process as claimed in any of the preceding claims, wherein said Group IV compound is titanium tetrachloride.
10. A process as claimed in any of the preceding claims, wherein said organo metal compound is an aluminium alkyl or a halide of alkyl aluminium.
11. A process as claimed in any of the preceding claims, wherein the organo metal compound is triethyl aluminium or triisobutyl aluminium.
12. A process for the homo or copolymerisation of olefines, substantially as described in any one of Examples 1 to 5.
13. An olefin homo or copolymer obtained by a process according to any one of Claims 4 to 12.
**WARNING** end of DESC field may overlap start of CLMS **.
Claims (13)
**WARNING** start of CLMS field may overlap end of DESC **. The yield is 139 g of polyethylene/g catalyst/h/atmosphere of ethylene. The specific activity of the catalyst component is 25.3 kg of polyethylene/ Ti/h/atmosphere of ethylene. The polymer has a melt index of 0.5 g/10 minutes. WHAT WE CLAIM IS
1. A catalyst for the homo or copolymerisation of olefines, obtained by reacting an organo metal compound of a metal of Group I, II OR III of the Periodic Table with the product of the reaction between a compound of a Group IV to Group VI metal and a support consisting of a partially hydrolysed aluminium compound, of the formula (I)
(I)
AIF (3-n) .nOH where:
n is a number of at least 0.01 and less than 3.
2. A catalyst according to claim 1, in which n is at least 0.05.
3. A catalyst according to Claim 1 or Claim 2, obtained by a process substantially as described in any one of Examples 1 to 6.
4. A process for the homo or copolymerisation of olefines containing 2 to 10 carbon atoms in accordance with the low pressure Ziegler method, in the presence of a catalyst according to Claim 1, Claim 2 or Claim 3.
5. A process as claimed in Claim 4, wherein the support as defined by the aforesaid formula (I) is obtained from a corresponding non-hydroxylated aluminium compound by treatment at a temperature of from 100 to 8000C for from 1 to 24 hours with water or aqueous ammonia or another inorganic substance or an organic substance either pure or in solution, suitable for introducing hydroxyl groups into the non-hydroxylated aluminium compound.
6. A process as claimed in Claim 4 or Claim 5, wherein aluminium fluoride is present in any one or more of its three allotropic forms, namely a-rhombic, p-hexagonal or y-tetragonal.
7. A process as claimed in any of the preceding claims, wherein said Group IV, V or VI metal is titanium, vanadium or chromium.
8. A process as claimed in any of the preceding claims, wherein said compound of a
Group IV, V or VI metal is a halide, oxyhalide or alkoxyhalide.
9. A process as claimed in any of the preceding claims, wherein said Group IV compound is titanium tetrachloride.
10. A process as claimed in any of the preceding claims, wherein said organo metal compound is an aluminium alkyl or a halide of alkyl aluminium.
11. A process as claimed in any of the preceding claims, wherein the organo metal compound is triethyl aluminium or triisobutyl aluminium.
12. A process for the homo or copolymerisation of olefines, substantially as described in any one of Examples 1 to 5.
13. An olefin homo or copolymer obtained by a process according to any one of Claims 4 to 12.
GB4205477A
1977-01-11
1977-10-10
Catalyst for the polymerisation of olefines
Expired
GB1588643A
(en)
Applications Claiming Priority (1)
Application Number
Priority Date
Filing Date
Title
IT1915177A
IT1074699B
(en)
1977-01-11
1977-01-11
HIGH ACTIVITY CATALYSTS FOR THE POLYMERIZATION OF ALFA-OLEFINE
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Publication Date
GB1588643A
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GB1588643A
(en)
1981-04-29
Family
ID=11155297
Family Applications (1)
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Title
Priority Date
Filing Date
GB4205477A
Expired
GB1588643A
(en)
1977-01-11
1977-10-10
Catalyst for the polymerisation of olefines
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AR
(1)
AR217262A1
(en)
CA
(1)
CA1105440A
(en)
GB
(1)
GB1588643A
(en)
IT
(1)
IT1074699B
(en)
MX
(1)
MX5181E
(en)
Cited By (1)
* Cited by examiner, † Cited by third party
Publication number
Priority date
Publication date
Assignee
Title
US5064796A
(en)
*
1991-01-07
1991-11-12
Exxon Chemical Patents Inc.
Support adjuvant for improved vanadium polymerization catalyst
1977
1977-01-11
IT
IT1915177A
patent/IT1074699B/en
active
1977-10-03
AR
AR26942477A
patent/AR217262A1/en
active
1977-10-05
CA
CA288,180A
patent/CA1105440A/en
not_active
Expired
1977-10-06
MX
MX645877U
patent/MX5181E/en
unknown
1977-10-10
GB
GB4205477A
patent/GB1588643A/en
not_active
Expired
Cited By (1)
* Cited by examiner, † Cited by third party
Publication number
Priority date
Publication date
Assignee
Title
US5064796A
(en)
*
1991-01-07
1991-11-12
Exxon Chemical Patents Inc.
Support adjuvant for improved vanadium polymerization catalyst
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Publication number
Publication date
IT1074699B
(en)
1985-04-20
CA1105440A
(en)
1981-07-21
MX5181E
(en)
1983-04-21
AR217262A1
(en)
1980-03-14
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Title
Description
1981-07-15
PS
Patent sealed
1986-06-11
PCNP
Patent ceased through non-payment of renewal fee