Magnesium dichloride-ethanol adducts and catalyst components obtained therefrom

Abstract

A solid adduct comprising magnesium chloride and ethanol in which the moles of ethanol per mole of magnesium chloride range from 2 to 5 and in which the ratio between the average pore radius measured in Angstrom of said adduct, determined by mercury porosity, and the moles of ethanol, is higher than 500.

Claims

1. A catalyst component comprising: a solid adduct, wherein the solid adduct comprises magnesium chloride and ethanol; wherein the moles of ethanol per mole of magnesium chloride ranges from 2 to 5, and wherein the solid adduct has a ratio between the average pore radius of the adduct measured in Angstroms, as determined by mercury porosity and due to pores up to 1 m, and the moles of ethanol per mole of magnesium chloride is higher than 500, wherein the mercury porosity is determined by intrusion of mercury under pressure using a porosimeter and the solid adduct has a mercury porosity ranging from 0.05 to 0.2 cm.sup.3/g with pores having an average pore radius from 0.18 to 0.35 m.

2. The catalyst component of claim 1, wherein the ethanol is present in an amount ranging from 2.2 to 4.5 moles.

3. The catalyst component of claim 1, wherein the solid adduct has a spherical morphology and an average diameter between 5 and 150 m.

4. The catalyst component of claim 1, wherein the solid adduct is prepared by (i) mixing MgCl.sub.2, and ethanol to form a MgCl.sub.2-ethanol adduct; (ii) heating the MgCl.sub.2-ethanol adduct at or above the melting temperature of MgCl.sub.2-ethanol adduct, until the adduct is completely melted; (iii) adding water until the melted MgCl.sub.2-ethanol adduct is present in a concentration in water of at least 0.8%, based upon the total volume of the MgCl.sub.2-ethanol adduct and water mixture; (iv) emulsifying the MgCl.sub.2-ethanol adduct and water mixture in a liquid medium which is immiscible with the MgCl.sub.2-ethanol adduct and water mixture, wherein the liquid medium is and chemically inert to the MgCl.sub.2-ethanol adduct and water mixture; and (v) quenching emulsion of step (iv) by contacting the emulsion of step (iv) with an inert cooling liquid producing the solid adduct.

5. The solid catalyst component of claim 4, wherein the solid adduct is reacted with at least one transition metal compound.

6. The solid catalyst component of claim 5, wherein the transition metal compound is TiCl.sub.4.

7. The solid catalyst component of claim 5, wherein the reaction between the transition metal compound and the solid adduct is carried out in the presence of an internal electron donor compound selected from the group consisting of diisobutylphthalate, n-butylphthalate, and di-n-octylphthalate and an external electron donor comprising cyclohexylmethyldimethoxysilane.

8. The solid catalyst component of claim 5, further comprising the product of the reaction between the solid catalyst component, and an organoaluminum compound.

9. The solid catalyst component of claim 8, wherein the organoaluminum compound is an Al-trialkyl compound.

10. The solid catalyst component of claim 1, wherein the solid catalyst component is contacted with an olefin of formula CH.sub.2CHR, in which R is hydrogen or a hydrocarbon radical having 1-12 carbon atoms, to product a polyolefin.

11. A process comprising polymerizing an olefin of formula CH.sub.2CHR, in which R is hydrogen or a hydrocarbon radical having 1-12 carbon atoms, by contacting the olefin with the solid catalyst component of claim 1 to produce a polyolefin.

12. The solid catalyst component of claim 1, wherein the ratio between the average pore radius of the adduct measured in Angstroms, as determined by mercury porosity and due to pores up to 1 m, and the moles of ethanol per mole of magnesium chloride is higher than 540.

Description

EXAMPLES

(1) General Procedure for the Preparation of the Catalyst Component

(2) Into a 11 steel reactor provided with stirrer, 500 cm.sup.3 of TiCl.sub.4 at 0 C. were introduced; at room temperature and whilst stirring 30 g of the adduct were introduced together with an amount of diisobutylphthalate as internal donor so as to give a Mg/donor molar ratio of 8. The whole was heated to 100 C. over 90 minutes and these conditions were maintained over 60 minutes. The stirring was stopped and after 15 minutes the liquid phase was separated from the sedimented solid maintaining the temperature at 100 C. A further treatment of the solid was carried out adding 500 cm.sup.3 of TiCl.sub.4 and heating the mixture at 110 C. over 10 min. and maintaining said conditions for 30 min under stirring conditions (500 rpm). The stirring was then discontinued and after 30 minutes the liquid phase was separated from the sedimented solid maintaining the temperature at 110 C. Two further treatment of the solid was carried out adding 500 cm.sup.3 of TiCl.sub.4 and heating the mixture at 120 C. over 10 min. and maintaining said conditions for 30 min under stirring conditions (500 rpm). The stirring was then discontinued and after 30 minutes the liquid phase was separated from the sedimented solid maintaining the temperature at 120 C. Thereafter, 3 washings with 500 cm.sup.3 of anhydrous hexane at 60 C. and 3 washings with 500 cm.sup.3 of anhydrous hexane at room temperature were carried out. The solid catalyst component obtained was then dried under vacuum in nitrogen environment at a temperature ranging from 40-45 C.

(3) General Procedure for the Polymerization Test

(4) A 4 litre steel autoclave equipped with a stirrer, pressure gauge, thermometer, catalyst feeding system, monomer feeding lines and thermostatting jacket, was used. The reactor was charged with 0.01 gr. of solid catalyst component 0.76 g of TEAL, 0.06 g of cyclohexylmethyldimethoxysilane, 3.2 1 of propylene, and 2.0 1 of hydrogen. The system was heated to 70 C. over 10 min. under stirring, and maintained under these conditions for 120 min. At the end of the polymerization, the polymer was recovered by removing any unreacted monomers and was dried under vacuum.

Example 1

(5) In a vessel reactor equipped with a IKA RE 166 stirrer containing 1062 g of anhydrous EtOH at 8 C. were introduced under stirring 547 g of MgCl.sub.2 and 11 g of water. Once the addition of MgCl.sub.2 was completed, the temperature was raised up to 108 C. and kept at this value for 20 hrs. After that, while keeping the temperature at 108 C., the melt was fed by volumetric pump set to 62 ml/min together with OB55 oil fed by volumetric pump set to 225 ml/min, to an emulsification unit operating at 2800 rpm and producing an emulsion of the melt into the oil. While melt and oil were fed in continuous, the mixture at about 108 C. was continuously discharged into a vessel containing 22 liters of cold hexane which was kept under stirring and cooled so that the final temperature did not exceed 12 C. After 24 hours, the solid particles of the adduct recovered were then washed with hexane and dried at 40 C. under vacuum. The compositional analysis showed that the particles contained 63% by weight of EtOH, 1.0% of water the remaining being MgCl.sub.2. The porosity, due to pores, up to 1 m was 0.106 cm.sup.3/g while the average pore radius was 2204. Its average particle size (P50) was 67.8 m. The SPAN was 1.6.

(6) Then, said adduct was used to prepare, according to the general procedure, the catalyst component the properties of which are reported in table 1. The catalyst was then used in a polymerization test carried out according to the procedure described above the results of which are reported in Table 2. In addition, part of the so obtained adduct particles have been subject to a mechanical stability test by ultrasounds treatment carried out according to the method described above. After 5 minutes treatment the P50 became 52.5 m while the SPAN was unchanged (1.6).

Example 2

(7) The same procedure described for example 1 was followed with the difference that 20 gr. of water were introduced.

(8) The compositional analysis showed that the particles contained 63.5% by weight of EtOH, 1.9% of water the remaining being MgCl.sub.2. The porosity, due to pores, up to 1 m was 0.152 cm.sup.3/g while the average pore radius was 2610. Its average particle size (P50) was 71.1 m. The SPAN was 1.8. Then, said adduct was used to prepare, according to the general procedure, the catalyst component the properties of which are reported in table 1. The catalyst was then used in a polymerization test carried out according to the procedure described above the results of which are reported in Table 2. In addition, part of the so obtained adduct particles have been subject to a mechanical stability test by ultrasounds treatment carried out according to the method described above. After 5 minutes treatment the P50 became 53.8 m while the SPAN became 2.0.

Comparative Example 3

(9) An MgCl.sub.2-EtOH adduct prepared according to the procedure of Example 1 with the difference that a lower amount of water was employed. The compositional analysis showed that the particles contained 64.4% by weight of EtOH, 0.5% of water the remaining being MgCl.sub.2. The porosity, due to pores, up to 1 m was 0.115 cm.sup.3/g while the average pore radius was 1640. Its average particle size (P50) was 67.3 m. The SPAN was 1.6. Then, said adduct was used to prepare, according to the general procedure, the catalyst component the properties of which are reported in table 1. The catalyst was then used in a polymerization test carried out according to the procedure described above the results of which are reported in Table 2.

(10) In addition, part of the so obtained adduct particles have been subject to a mechanical stability test by ultrasounds treatment carried out according to the method described above. After 5 minutes treatment the P50 became 33.8 m while the SPAN became 2.6.

Example 4

(11) The adduct prepared according to the procedure of Example 2 was thermally dealcoholated under nitrogen flow until the content of EtOH reached 54.3% b.w, while the water content was 1.8%. The so dealcoholated adduct showed a porosity of 0.258 cm.sup.3/g and an average pore radius of 1774. Then, said dealcoholated adduct was used to prepare, according to the general procedure, the catalyst component the properties of which are reported in table 1. The catalyst was then used in a polymerization test carried out according to the procedure described above. The results are reported in Table 2.

Example 5

(12) The adduct prepared according to the procedure of Example 2 was thermally dealcoholated under nitrogen flow until the content of EtOH reached 55.6% b.w, while the water content was 1.8%. The so dealcoholated adduct showed a porosity of 0.237 cm.sup.3/g and an average pore radius of 1807. Then, said dealcoholated adduct was used to prepare, according to the general procedure, the catalyst component the properties of which are reported in table 1. The catalyst was then used in a polymerization test carried out according to the procedure described above. The results are reported in Table 2.

Example 6

(13) The adduct prepared according to the procedure of Example 2 was thermally dealcoholated under nitrogen flow until the content of EtOH reached 57.5% b.w, while the water content was 1.8%. The so dealcoholated adduct showed a porosity of 0.151 cm.sup.3/g and an average pore radius of 2065. Then, said dealcoholated adduct was used to prepare, according to the general procedure, the catalyst component the properties of which are reported in table 1. The catalyst was then used in a polymerization test carried out according to the procedure described above. The results are reported in Table 2.

Comparative Example 7

(14) The adduct prepared according to the procedure of Comparative Example 3 was thermally dealcoholated under nitrogen flow until the content of EtOH reached 57.2% b. w. the water content was 0.4% b.w. The so dealcoholated adduct showed a porosity of 0.229 cm.sup.3/g and an average pore radius of 1069. Then, said dealcoholated adduct was used to prepare, according to the general procedure, the catalyst component the properties of which are reported in table 1. The catalyst was then used in a polymerization test carried out according to the procedure described above. The results are reported in Table 2.

Comparative Example 8

(15) The adduct prepared according to the procedure of Comparative Example 3 was thermally dealcoholated under nitrogen flow until the content of EtOH reached 54% b. w. the water content was 0.4% b.w. The so dealcoholated adduct showed a porosity of 0.249 cm.sup.3/g and an average pore radius of 1155. Then, said dealcoholated adduct was used to prepare, according to the general procedure, the catalyst component the properties of which are reported in table 1. The catalyst was then used in a polymerization test carried out according to the procedure described above. The results are reported in Table 2.

(16) TABLE-US-00001 TABLE 1 Ti Mg ID Example % wt % wt % wt 1 2.9 19.3 10.1 2 3.3 19.2 9.6 Comp. 3 2.7 19.4 10.8 4 3.1 19.4 8.9 5 3.0 19.5 8.9 6 2.8 19.2 10.2 Comp. 7 2.7 19.3 11.3 Comp. 8 3.1 18 13.4

(17) TABLE-US-00002 TABLE 2 Polymer Porosity Polymer Example Activity I.I (cm.sup.3/g) Breaks 1 66 96.9 nd Nd 2 64 96.8 nd Nd Comp. 3 56.6 97.5 nd nd 4 69.7 97.2 0.183 3.7 5 73 97.6 0.186 3.8 6 73.3 97.6 0.126 nd Comp. 7 67.2 97.5 0.095 4.5 Comp. 8 60.4 93.8 nd 4.3