DK144704B - PROCEDURE FOR POLYMERIZATION OF ALFA OLEFINES AND CATALYST SYSTEM FOR USE BY THE PROCEDURE - Google Patents

Description

(19) DENMARK

É | (12) PRESENTATION WRITING ου 144704 B

DIRECTORATE OF THE PATENT AND TRADEMARKET SYSTEM

(21) Application No. 1257/75 (B1) IntCI. * C 08 F 10/00 (22) Filing day 25 · Mar. 1975 C 08 F 4/64 (24) Race day 25 · tnar. 1975 (41) Aim. available 29 Sep 1975 (44) Submitted May 17, 1982 (86) International Application No. - (86) International Filing Day (85) Continuation Day - (62) Standard Application No. -

(30) Priority 28. weird. 1974, 49832/74, IT

(71) Applicant SNAMPHOGETTI S.P.A., Milan, IT.

(72) Inventor Sebastiano Clesca, IT: Alberto Greco, IT: Guglielmo

Bertolinl, IT: Mario Bruzzone, IT.

(74) International Patent Bureau.

(54) Process for polymerizing alpha-olefins and catalyst system for use in the process.

The present invention relates to a process for the polymerization of α-olefins, especially ethylene, by means of a catalyst system sanitized by an aluminic acid alkylation and a core atomic product of a transition metal chloride and titanium trichloride which is finely dispersed on a material having a large content. surface area: the invention further relates to the catalyst system used. It is known that titanium halides that are catalytically active are used in the polymerization of low pressure α-olefins. These halogenides have been prepared by reducing titanium tetrahaloids with aluminum alkyl or aluminum alkyl halohexide compounds. The reaction is usually carried out under an inert atmosphere and in the presence of an inert solvent. The catalyst thus obtained

Q

Is then combined with metal alkyl compounds to polymerize α-olefins in suspension in an organic solvent under reasonable pressure of the monomer.

However, these titanium halides are impure due to the presence of aluminum compounds and do not exhibit a particularly high catalytic effect, so that the final polymer requires costly washing operations to remove the catalyst residues.

In the past, methods have been proposed according to which titanium halides, optionally together with vanadium halides, are carried on inorganic substances to obtain polymerization catalysts with improved efficiency. For example, magnesium oxide or hydroxide sati carrier; however, it should be noted that the catalytic activity of the titanium compound carried on these materials varies widely, depending on the chemical nature of its surface. Therefore, in many cases, to improve their efficiency, such compounds must be treated with Grignard reagents, aluminum alkyl compounds or hydrogen.

It is an object of the invention to provide a process for the polymerization of α-olefins by a catalytic system which has a high activity and does not require any prior treatment of the support.

The process according to the invention is characterized in that the reaction is carried out in the kidney room of a catalyst system composed of an aluminum compound selected from AIR and AIR Y

represents an alkyl, aryl or cycloalkyl group, x is a number between 1 and 2, Y represents halogen or hydrogen, and of a combination product prepared by treating a carrier consisting of one or more oxides of Group II-IV elements thereof periodic system with a solution of a cafbonyl compound of vanadium, manganese or cobalt, the amount of transition metal being 0.1-10% by weight, preferably 1-3% by weight, based on the weight of the carrier, and then reacting the impregnated carrier with titanium tetrachloride.

Said combination product is very stable from a chemical point of view since titanium trichloride and transition metal chloride are isostructural; moreover, it contains titanium in the optimum valence to obtain the best catalytic activity.

For example, in the preparation of the combination product, proceed by impregnating the carrier, which is already dehydrated by thermal treatment, with the carbonyl compound dissolved in a hydrocarbon solvent, treating the thus impregnated carrier with refluxing titanium tetrachloride and finally removing the excess titanium tetrachloride.

During the process, carbon monoxide is developed and the oxidation of the metal and the simultaneous reduction of titanium tetrachloride to the trichloride occur after the following reaction.

M (CO) p + n TiCl4-> MCln, n TiCl3 + p CO

wherein p represents the number of carbonyl groups and n represents the valence of the transition metal M during its oxidation by titanium tetrachloride.

The material used as a carrier in the above reaction is, as mentioned, selected from the oxides of elements belonging to groups II-IV of the periodic system. The material is more particularly selected from silica, s alumina-alumina, ZnO 2,

MnO, TiO2 and CaO.

As stated above, pretreatments of the support are not necessary as the activity of the catalyst systems in question is high and uniform, although the chemical nature of the support is subject to change. However, such carriers may also be subjected to pretreatments with Grignard reagents or aluminum alkyl halides so as to further enhance performance.

In any case, the activities observed by polymerization are greater than those obtained by the TiCl 2 -carriers only under the same conditions.

The catalyst system used exhibits good behavior in the presence of hydrogen and, in the case of ethylene polymerization, results in a narrow molecular weight distribution.

The invention also relates to said catalyst system, which is characterized by the claim 5.

The polymerization reaction is carried out in a known manner at temperatures of 0-200 ° C and at pressures of 0.1-50 atmospheres.

The polymerization is carried out in steel autoclave equipped with an anchor stirrer when the operations are carried out at pressures greater than atmospheric. The catalyst is introduced together with the solvent and the metal-alkyl compound.

The autoclave is adjusted with thermostat to the polymerization temperature, H2 and then ethylene is introduced therein under pressure at the desired pressure ratio. The reaction is stopped by adding alcohol to the autoclave.

4 U4704

The solvent, the organic metal compound (Al (xC + Hg) 2 at a concentration of 0.2% by volume) and the transition compound combination product prepared as indicated are introduced into the autoclave maintained by 85 ° C by thermostat, cf. the following examples. . Ethylene pressure is kept constant throughout the experiment, which is completed in 6 hours. The procedures described in the following examples apply these operating conditions (standard polymerization).

The obtained polymers are dried under vacuum to constant weight before evaluating the yields of the polymer.

The following examples further explain the invention.

Example 1 100 g SiC 2 / A 2 And with low AlgOg content, surface area OA = 400 m 2 / g / was treated under reflux in boiling xylene for azeotropic removal of water. The product was dried, filtered under nitrogen and washed with hexane, added 3 g of tetracarbonylvanadine-cyclopentadienyl, V (CO) + Cp, in 200 ml of hexane. This solvent was removed by rotary evaporator, and the yellow material which was air sensitive was suspended in 200 ml of TiCl 2 and refluxed for 6 hours. During this time, the material turned dark purple. Then it was filtered, washed several times with hexane and dried in vacuo. By analysis, the following composition showed:

Ti 7.30% V 0.40%

Cl 12.54% 240 mg of this catalyst was used in standard polymerization of ethylene at partial pressure e ~ = 13 atm, and C-H. = 8 atm. 500 g * 135 ° C 4 polyethylene was obtained with MF21 6 ~ decalin = ^ 1 / g and containing 36 ppm Ti + V, wherein Ti was approx. 33 ppm.

Comparative Example for Example 1.

The SiOg / AlgOg used in Example 1 was treated under reflux under the same conditions, but only with titanium tetrachloride. After the same treatment, the white material which was air sensitive gave the following analysis results:

Ti 4.10%

Cl 7.98% 5 1 470Λ 224 mg of this catalyst gave, under polymerization conditions as

135 ° C

the 60 g polymer described with Example 1 with MF21 6 = 0.2, [fl] <jeca-L ^ n = 6.6 dl / g and a Ti content of 150 ppm.

Example 2 25 g SiC> 2 (> 99%), OA = 400 m g, was dehydrated by azeotropic distillation with xylene as in Example 1, treated with 0.65 g of V (CO) 4Cp in hexane (50 ml) and then after removal of the hydrocarbon solvent treated with liquid TiCl4 (50 ml) under reflux, in the same for a period of time and according to the same technique as described in Example 1. The color of the catalyst thus obtained was dark violet. By analysis, the composition was found!

Ti 4.65% V 0.40%

Cl 8.24% 105 mg of the catalyst thus obtained was used for standard polymerization at relative pressure H2 / C2H4 = 10/10 atm. 102 g of polyethylene were obtained with MF21 6 = 9 of Ti + V of 52 ppm, with Ti being 46 ppm.

Example 3 85 g of SiO 2 / Al 2 O 3 of the same type as used in Example 1 was dried in a muffle oven at 400 ° C for 24 hours and then impregnated with 4.0 g of Mn 2 (CO) 1Q in 200 ml of hexane. The solvent was removed by a rotary evaporator and the orange-yellow solid was treated in boiling TiCl 3 under reflux for 6 hours. The filtered violet material, washed with hexane and dried in vacuo, showed the following analysis;

Ti 5.73%

Mn 1.35%

Cl 12.60% 169 mg of this product used in standard polymerization experiments at 13 atm. H2 and 8 atm. C2H4 gave 151 g of polyethylene with MF2 ^ g = 0.350, MF22 g = 15.684, MF21 g / MF2 16 = 44, ^ = 3.3 dl / g and 79 ppm Mn + Ti, where Ti was 64 ppm.

144704 6

Example 4 416 mg of the product described in Example 3, used in a standard polymerization at relative pressure H 2 / C 2 H 4 = 10/5 atm, gave 55 3 P ° of gylene with ®2.16 = 5'1616 "21, 6 = 211'6 '"21.6 / MF2.16 = 41, t ^ l ^ ecaline = 1.6 dl / g and a content of Ti + Mn of 229 ppm, wherein Ti was 185 ppm.

Example 5 260 mg of the product used in Example 3 was used in a standard polymerization, replacing Al (i-C4H9) 3 with AlEt2Cl and operating at relative pressures H2 / C2H4 in 10/10 atmospheres. 120 g of polymer was obtained with MF2 Ig = 0.135, MF21 g = 8.727, MF21 g / MF2 Ig «64, decalin = 3.5 and a Ti + Mn content of 153 ppm, with Ti being 124 ppm.

Example 6 25 g of finely powdered MgO, dried in muffle oven at 400 ° C overnight, were reacted with 1.5 g of Co2 (CO) g in 100 ml of hexane. The solvent was then removed by rotary evaporator while the residue was treated under nitrogen in TiCl 4 (100 ml) under reflux for 8 hours. Heat filtered, a violet powder, which was washed several times with hexane and dried under vacuum had the following composition:

Ti 3.70%

Co 1.55%

Cl 31.15% 31 mg of the product thus obtained was used in a standard polymerization at a H 2 pressure of 10 atmospheres and a C 2 H 4 pressure of 10 atmospheres. 250 g of polyethylene were obtained with MF2 ^ g = 0.869, "21.6 - 34'97" ®21.6 / MF2.16 "40'2" "" decaUn = ^ 92 dl / 3 03 content of Ti + Co of 6.5 ppm, wherein Ti was 4.6 ppm.

Example 7

A commercially available MgO portion was hydrated in water at 80 ° C for 4 hours and then dried in a muffle oven at 400 ° C in air for 24 hours, 20 mg of the thus treated MgO was impregnated with V (CO) 4Cp (1 , 2 g) in hexane (100 ml) and the solvent was removed by a rotary evaporator. The dry residue was then treated in boiling TiCl 4 (100 ml) under reflux for 4 hours. A violet product was filtered, washed and vacuum dried, which product had the following composition:

Ti 3.31% V 0.58%

Cl 35.23% 20 mg of this catalyst was used in a standard polymerization at relative pressure H2 / C2H4 = 10/10 atm. 235 g of polyethylene were obtained with MF 2 + g = 1/203, MF 2 + g = 49.03, MF 2 6 6 = 2 16 = 2 decalin = dl / g and containing 3.3 ppm Ti + V, wherein Ten was 2.8 ppm.

Comparative Example for Example 7.

20 g of MgO, treated by the procedure of Example 7, was treated in boiling TiCl 4 (100 ml) for 4 hours under reflux.

A white solid was then filtered off, which was washed and vacuum dried to show the following composition:

Ti 1.43%

Cl 31.62% 42 mg of the catalyst was used for comparison in a standard polymerization performed as described in Example 7. 81 g of polygthylene were obtained with MF2 ^ = 1.81, MF ^ g = 44, MF ^ g / MF2 16 = 36'3 'to] decalin = 2'73 dl / g ° 9 a Ti content of 7.4 ppm!

Example 8 25 g of SiO 2 of the same type as used in Example 2 was dehydrated by azeotropic distillation with xylene and reacted with 2 ml of AlEtCl 2 in hexane (100 ml). The suspension was then added with V (CO) + Cp (1.0 g) and then the solvent was removed by a rotary evaporator. The material thus obtained was treated with boiling TiCl 2 for 6 hours under reflux. After filtration, washing with hexane and vacuum drying, the violet product had the following composition:

Ti 2.97% V 0.86%

Al 1.90%

Cl 8.59% 192 mg of the catalyst thus obtained was used in a standard polymerization at relative pressure H2 / C2H4 of 10/10 atm. 96 g of polyethylene were obtained with MF2 Ig = 0.335, MF21 g - 14.1, MF21 g / MF2 Ig = 42.1, [η] = 2.63 dl / g and a content of Ti + V of 80 ppm, wherein Ten was 60 ppm.

Claims (3)

Example 9 25. SiO2 / Al2O3 of the same type as used in Example 1, dried overnight in an oven at 200 ° C, was treated with an ethereal solution of chlorobutyl-Grignard reagent (10 ml, solution 1: 1 ml). in 10 ml of hexane. The solvent was evaporated on a rotary evaporator and then 1.2 g of V (CO) 2 Cp was added in 100 ml of hexane. After removal of the solvent by means of an evaporator, the dry product was treated in boiling TiCl 4 for 6 hours at reflux, after which a violet solid was filtered, washed and dried. It had the following composition: Ti 9.20% V 0.74% Mg 1.07% Cl 21.85% 212. of this product, used in a standard polymerization of 7.5 atm. ethylene and 15 atm. H2 gave 325 g of polyethylene with MF2 Ig = 1.014, MF21 6 = 45.44, MF21 g / MF2 Ig = 45.44, [η] = 2.0 dl / g and containing 65 ppm Ti + V, where Ti was 61 ppm. A process for polymerizing α-olefins using a catalyst system consisting of an organoaluminum compound and on an oxide support finely divided transition metal chloride and titanium trichloride, characterized in that the reaction is carried out in the presence of a catalyst system composed of an aluminum compound selected from AIR, and AIR Y, wherein R represents an alkyl, aryl or cycloalkyl group, x is a number between 1 and 2, Y represents halogen or hydrogen, and of a combination product prepared by treating a carrier consisting of a number of oxides of elements of Group IX-XV of the Periodic Table with a solution of a carbonyl compound of vanadium, manganese or cobalt, the amount of transition metal being 0.1-10% by weight, preferably 1-3% by weight, based on the weight of the carrier, and then reacting the impregnated carrier with titanium tetrachloride. Process according to claim 1, characterized in that the olefin used is ethylene. Process according to any one of the preceding claims, characterized in that the reaction is carried out in the presence of a hydrocarbon solvent.