CA1077460A - Catalysts for polymerizing olefins - Google Patents

Abstract

ABSTRACT OF THE DISCLOSURE:
New catalysts for the polymerization and copolymeri-zation of olefins are disclosed. The catalysts are prepared from (1) a new class of metal compounds containing at least one atom of Mg, Mn or Ca and at least one atom of Ti, V or Zr and (2) organometallic compounds of metals belonging to one of Groups I to III of the Mendelyeev Periodic Table.

Description

1C)77460 . . .
It is known to polymerize and copolymerize ethylene in the presence of catalysts of various types, and in particular catalysts consisting of the product of reaction between a compound of Ti, V or Zr and an organomet~llic compound of a Group I to III metal.
Among the titanium compound~ suggested for use were the halo-titanates having the formula M2TiXn+2, in which M i9 an alkali metal or a quaternary ammonium group; X i~ a halogen, preferably Cl or Br; and n is the titanium valence. Some t~pical compounds of this class are Na2TiC16; ~2TiC16; and [N(C2H5) ~ 2 ~iC16-The catalysts prepared starting from the above-mentloned halo-titanates exhibit a very low activity in the polymerization of ethylene and alpha-olefins and are generally much less active than the corresponding titanium halides.
For this reason, they are not employed in the com- ~ -mercial production of polyolefins.
With one exception, the halo-titanates having the formula M2~iXn+2, in which N iB a metal of Group II of the Mendelyeev Periodic ~able were unknown heretofore. The ex-CeptioD is MgTlF6 which, however, exhibits no meaningful catalytic activity ln the polymerization of olefins.
Surpri~ingly , we have found it iB possible to use, a~ one component of catalysts for olefin polymerization, a Dew class of metal compounds containing at least one atom of Mg, Mn or Ca and at least oDe atom of ~i, V or Zr. Such compounds, when combined with organometallic compounds of the metals belonging to one of Group~ I to III of the Mendelyeev Periodic Table provide catalysts which are very hi~hly active in the polymerization of olefins.
The new catalyst component~ of this invention are complexes having the general formula - 1 _ 10774~i0 MmM'X2mY-nE
wherein M = Mg, Mn and/or Ca;
m - a number from 0.5 to 2;
M'- Ti, V and/or Zr;
X ~ Cl, Br or I;
Y = one or more atoms or groups of atom~, which may be the same or differeDt, selected from atoms of halogen; atoms of halogen and, con-temporaneously, atoms of oxygen; -NR2; -OR; -SR
-O-C-R; -O-~-R; (in which groups R is a hydro- . :-carbon radical, in partioular an alkyl, aryl, cycloalkyl or aralkyl radical), acetylacetonate anion; acetylacetonate anion and, contemporaneous- .:
ly o~ggen atom~; the eroups or atoms being present in such an amount as to satisfy the ~alence of M';
n , number from 0.5m to 20m;
E - an electron-donor compound selected from the following cla~ses of compounds:
(a) esters of organic carbo~ylic acids;
(b) alcohols;
(c) ethers;
(d) amines;
(e) esters of carbonic acid;
(f) nitriles;
(g) phosphoramides, esters of phosphoric and phosphorous acid and phosphorus oxychlorids.
In the above formula, a portion of the ~i, V and~or Zr may be substituted by metals selected from Zn, Al, SD and transitioD metals, such as Fe, Co, Ni, Cr, Mo in such an amount that the atomic ratio between such metals and ~i, V and/or Zr '

- 2 -~ 77460 will range from 0.1:1 to 2:1.
Among the cited classes of uaeful electroD-donora (a) to (g), particularly interesting reaults are obtaiDed with alkyl esters of aliphatic or aromatic acida in whi¢h the alkyl radical contains from 1 to 8 carbon atoms; ROR' ethers iD which R and R', the same or dlfferent, are alkyl radicals contaiDing from 1 to 8 carbon atoms or aryl radicals; aromatl¢ nitriles; and alkyl r' esters Or phosphoric or phosphorou~ acid, in which the alkyl 4 radicals contain from 1 to 8 oarbon atoms.
Typical compounda of the laat-mentioned preferred cla~ses Or electron-donors, which have given the best results ae regards the activity of the catalysts obtained from them, are: ethyl acetate, ethyl benzoate, diethyl malonate, methanol, ethanol, ethyl ether, tetrahydrofuran, pyridine, ethylene carbon-ate, benzonitrile, phosphorus oxychloride, hexamethyl phosphor-; ~mi de and triphenyl phosphite.
The new catalyst-forming complexea can be prepared by reacting, in sultable ratios, the halide MX2 with the compound M'Y, at a temperature of from room temperature to 150C, in ~ 20 particular solvents E which act as electron-donor compounds, and are isolated by crystallization from the same aolvent, by evaporation of the sol~ent, or by precipitation with a solvent in whi¢h the complexes are insoluble.
If the halide ~ , the compound M'Y, or both, are poorly soluble in solvent E, the reaction can be carried out in another suitable electron-donor ~olvent E', to obtain a complex ~M'X2mY.nE' which, after isolation, can be treated, at a temperature of from room temperature to 150C, with an excesa of solvent E that shift~ ~ol~ent E'. To effeot such ~hift, it ia also pos~ible to mix an excesa o~ solvent E with the sQlution of the complex ~ M'~ mY.nE' in aolvent E~.
In general, the molar ratio of the reactants MX2 to M'Y

~; `

,: :
; correspoDds to the value of m in the complex to be prepared.
However, it is also possible to obtain very active catalyst-forming components by using an exce~s of halide ~ with respect to the amount usually used for preparing the desired complex, i.e., a M~2/M'Y molar ratio higher than 2. In that case, by cry3talllzatlon, by evaporation Or the solvent, or by precipi-tation wlth a suitable solvent, a mixture iQ isolated conæisting Or the desired complex or the complex containing the solvent E~
and of a complex made up Or halide M~2 and of solvent E or solvent E'.
; Analogously, it i8 possible to use an exce~s of compouDd M'Y over the amount usually employed to obtain the desired complex, i.e., a M'Y/M~2 molar ratio higher than 2. In that event, a mixture is isolated consi~ting Or the de~ired complex or the complex containing solvent E', and of a complex -~
oonsisting of compound M~Y and solvent E or ~olvent El.
It is also possibl6 to uee mi~ure~ Or said performed complexes of the invention wlth an anhydrow Mg dihalide, the X-ray spectrum Or said mixtures showing a halo having an iD-tensity peak shifted with respect to the interplanar distance of the most intense line appearing in the 9pectrum of the Mg dihalide of normal type. The spectrum of Mg dichloride and -;
dibromide of norm~l type is defined in AS~M 3-0854 for the dichloride and in AS~M 15-836 for the dibromide.
The content Or Mg dih~lide is compr~sed between 1 and 99~ by wt., more particularly between 20 and 80%, Said mixtures ¢an be prepared, for example, by co-grinding the components under ¢onditions such that the X-ray speotrum of the ground produ¢t shows the above modifi¢ation.
The Ti, V and Zr compounds useful for preparing the new catalyst-forming complexes of the invention include: TiC12, TiC13, TiCli, ~iOC12, ~iBr4, ~iI4, C13TiOCH3, C12Ti(OC4Hg) ,. . . . . .
, 7741;~

~( 4 9)4, C13TiN(C6H5)2- C13TiCC6H5, Cl32~sc6H5~ C13~i -acetyla¢etonate, C13~iOS02C6H5, C13TiOC6H5, V 3, 4 3 C12VOC4Hg, V(OC4Hg)3, ClV(acetylacetonate)2, C12VOCOC6H5, VO-acetylacetQnate, ZrC14, C13ZrOC4Hg.
Complexes within the general formula ~M'X2mY.nE
include:
MgTiC15.2CH3COOC2H5 Mg3~12C112 . 7CH3aOOa2H5 MgTiC15.6C2H50H
MgTlGl5.locH3oH
MgTiC15.5 tetrahydrofuran Mg3!ri2C112 7C6H5CN
Mg3Ti2cll26G6H5~ 00C2H5 MgTiC16 .2CH3COOC2H5 ~OCH2 MgTiC16 . 9CO'~ ¦

NgTlC16-6C5H5N
MgTiC15(0CH~). 2CH3COOa2H5 MgTlclsN(c6H5)2-3cH3cooc2H5 g 1 2 14.2(C2H5)?0 MnTlC15.4C2H50H
Mg3V2C112.7CH3COoC2H5 MgZrC16.4 tetrahydrofuran.
Organometallic compound~ wbich are particularly sultable for use as second cataly~t-forming com~oneDt in the preparation of the catalysts of the invention are: Al~ (C2H5)3, Al(C2H5)2Cl, Al(l-C4Hg)3. ~1(1-C4H9)2Cl~ A12( 2 5 3 3 AL(C2H5)2H' Al(l-C4H9)2H' ~l(a2Hs)2Br~ (C2H5)~ o_Al(C2H5)2, ( 2 5)2Al IN Al(a2H5)2, (C2H5)2A10 - O - OAl(C2H5)2, ~iAl(i-C4Hg)4~ Li-i-C4Hg- Zn(C4H9)2' . ' .:. - - -- .

.. . .
~ he molar ratio between the organometallic ¢ompound and the complex containing Ti, and/or V, and/or Zr is not crlti-cal. For polymerizing or copolymerizing ethylene and alpha-olefins it i8 preferably comprised between 10 and 1,000.
The catalysts of this invention are employed in the polymerization or copolymerizatior of olefins, in particular of ethyleDef propylene, butene-l and 4-methylpentene-1 by conventional technique~, i.e., in a liquid phase, either in the presence or absence of an inert solveDt, or in gas phase. An aliphatic or cycloalyphatic hydrocarbon, such as, for example, hexane, heptane cyclohexane, ma~ be used as inert polymerization solvent.
The (co) polymerizatlon temperature may be comprised between -80C and 200C, preferably between 50C and 100C, operating at atmospheric pressure or under pressure. Regulation of the molecular weight of the homopolymer or copolymer produced can be effected by known methods, rOr example by carrying out the polymerization reaction in the presence of known molecular weight regulators, such a~ alkyl halides, organometallic ¢ompounds of Zn or Cd, or hydrogen.
The following examples are given to illustrate the invention and are not intended to be limiting.
; EXAMPLE 1 l.lg of ~ial3 Or the HR type, prepared by reduction ~ iC14 with H2,(7.1 m. moles) are dis~olved, in a nitrogen atmosphere, in 100 ml of anhydrous ethyl acetate.
Similarly, 0.68 g of anhydrou~ MgC12 (7.1 m. moles) are dissolved in 31 ml of anhydrous ethyl acetate.
The two solutlons are mixed and reacted at 60C for 2 hours. ~he extremely soluble reaction product was isolated by evaporation of the solve~t.
A grey-green powder ~A) was thu~ obtained that .. ~ . . . . .. .

1~774~(~
:`
revealed, o~ analy3is, a composition corre~ponding to ~ormula ,, MgTiC15 . 2CH3COOC2H5 .
The X-ray diffraction pattern and the infrared absorption band~ characteristi¢ of group ~ C=0 revealed that ~uch product was a well-defined compound.
By way of compari~on, complexes TiC13.CH3COOC2H5 and MgC12.CH3COOC2H5 and their mechanical mixture in a 1:1 molar ratio were examined. The X-ray and infrared spectra were entirely differeDt from those of product (A).
The ethylene polymerization test~ carried out by using, a~ catalyst components, the complexe~ MgTiC15.2CH3COOC2H5, TiC13.CH3COOC2H5 and the above-cited mechanical mixture are reported in the ~able below (Teæts I, II and III).
~XAMPIE 2 6.92 g of anhydrous MgC12 (72.7;m. moles) are dis-æolved, in a nitrogen atmosphere, in 100 ml of anhydrous ethyl acetate. Analogously, 7.48 g of TiC13 o~ the HR type (48.46 m. mole~) are dissolved in 72 ml of aDhydrous ethyl - acetate. The two ~olutions are mixed and reacted under stirr-ing for 4 hour~ at 60C. ~he re~ulting reaction product i8 extremely 301uble and i9 isolated by evaporation of the solvent.
A light green powder (A) i9 obtained. ~y analy3is;it was found to have a compo~ition corre~ponding to formula Mg3Ti2C112.7CH3 The X-ray pattern of such product (A) exhibit~
diffraction3 attributable neither to TiC13.CH3COOC2H5 nor to MgC12.2CH3COOC2H5; similarly, the ab30rption band~ of ; group C,0 i~ the infrared spectrum have po~ition~ different from those corresponding to the complexe~ of TiC13 and of MgC12 with ethyl acetate.
The ethyle~e polymerization te~t~ U~iDg such complex (A) a~ catalyst component are reported in the Table (te~ts IV and V).

- ~ -.: - : ~ . . . . .
..

`~^` ~774~0 ....
I~ a nitrogen atmo~phere, 0.95 g of TiC13 of the HR
type (6.1 m,moles) and 0.65 g of anhydrous MgC12 (6.1 m.mole~) are separately dl~solved, respectively, in 80 ml of deaerated aDhydrous ethyl alcohol aDd in 20 ml of the same alcohol.
The two solutions are gathered and reacted at room ; temperature for 12 hours. ~he reaction product i~ isolated by ; evaporation Or the ~ol~ent and dried. A grey powder is thus obtained. OD aDaly~is it has a compo~ition correspoDdine to the formula: MgTiC15.6C2H50H. ~he ethylene pol~merizatioD
condu¢ted by U8iDg su¢h complex as catalytic component is reported in the Table (test VI).
EXAMPLE 4 ~ -In a nitrogen atmosphere, 1.4 g of ~iC13 of the HR
type ~9.05 m. moles) and 0.86 g Or anhydrous MgC12 t9.05 m-moles) are separately dissolved in, respecti~ely, 100 ml of deaerated anhydrous methanol and in 50 ml of the same al¢ohol. ~he two solutioDs are mi~ed and reacted at 50G for 4 hours. The reaction product 18 isolated by e~aporation of the solvent and dried.
The grey powder ~o obtained has, on analy~is, a ,composition oorre~ponding to the formula: MgTiC15.10CH39H.
The polymerization of etkyle~e condu¢ted by employing such ¢omple~ a~ ¢atalyti¢ compo~Dent i8 reported in the Table (test VII).
EXAMPLE_~
In an inert atmosphere, 2.4 g (10 m. moles) of MgC12.
.2tetrahydrofuran and 3.6 g (10 m. mole~) of TiC13.3 tetra-h~drofuran are separately dissolved in, reope¢tively, 300 ml of anhydrous tetrahydrofuran and in 200 ~1 of anhydrou~ tetra-hydrofuran. The two ~olutions are gathered and reacted under stirring at room temperature for 2 hour~. ~he product i3 , . . , . .. . - , .

10774~0 isolated by evaporatioD of the 801~ent aDd dried.
A grey powder i8 thus obtaiDed. On analy~ie it has a composition correspondlng to the rormula: MgTiC15.5 tetrahydrofuran.
The ethylene polymerization ¢arried out by usiDg such ¢omplex as catalyst component i8 reported iD the ~able (test VIII).

2.8 g Or anhydrou~ MgC12 (29.5 m. moles) are dissolved in 59 ml of aDhydrous ethyl acetate. Separately, 4.4 g of TiC13ARA, prepared by reductioD of TlC14 with metal Al and acti~ated by dry grinding, (22.1 m. moles) are di~solved in 60 ml of anhydrous ethyl a¢etate. ~he two solutions are gathered and allowed to react at 50G for 4 hours.
~he resultiDg dark greeD solution is e~aporated to dryness, thus obtaiDing a ~iolet solld which, OD analysis, has a composition corre~ponding to the formula: Mg4Ti3AlC120.
.12CH3COOC2H5. ~his complex contained also Al due to the fact that TiC13 prepared by redu¢tlon of ~lC14 with Al was in the rorm of 3TiC13.AlC13, known as ~iC13 ARA.
The ethylene polymerization te~t conducted by using such complex as catalytlc component i9 reported ln the ~able (test IX).
EX~ E~
1.6 g Or the complex Or formula Mg3~12C112.7CH3COOC2H5, prepared as described in Example 2, are suspended in 30 ml of ethyl benzoate and the suspenslon thus obtalned is heated to 100C ror 6 hour~. The reaction product i9 filtered, wa~hed at`room temperature with 200 ml o~ n-heptane, and dried under ~acuum.
~he yellow solid 80 obtained exhibited, on analysis, a composition corre~ponding to formula Mg3Ti2C112.6C6H5COOC2H5.

_ 9 _ ~774~0 The ethylene polymerizatlo~ tests carried out by using such complex as catalyst ¢omponent are reported ir the Iable (tests ~, Xl and XXXVI).

1.8 g of the complex having the ~ormula Mg3Ti2C112.
.7C~ COOC2H5, prepared according to Example 2, are su~pended in 30 ml of benzonitrile. Following the modalities of Example 7, a brow~n solid was isolated, that e~hibited, on analysis, a composition corresponding to formula Mg3Ti2C112.7C6H5CN.
The ethylene polymerization conducted by e~ploying such complex as catalytic component is reported in the ~able (test XII).
EXAMP~E 9 In a nitrogen atmo~phere, 2.6 g of anhydrous MgC12 (27.4 m. moles) and 3 ml oi ~iC14 (27.4 m. mole~) are dissolved separately i~ 200 ml of anhydrous ethyl acetate and in 60 ml of anhydrous ethyl acetate, respectively. ~he two solutions are gathered and reacted under stirring ~or 4 hour~ at 60C. From the concentrated solution a yellow crystalline solid precipi-20 tates on cooling, which i8 the~ isolated, recrystallized iromethyl acetate and dried under vacuum at 50C. Such product, that decomposed at 190C, revealed on anal~si~ a composition corresponding to formuia NgTiC16.2CH3COW 2H5.
~ he inirared and X-rays spectra oi such product reveal that it is a well-defi~ed compound, being thoroughly different from the infrared and X-rays spectra of the comple~e~
¦~icl4~c~3cooc2H5l2 and MgC12-CH3COOC2H5-The etbyle~e polymerization te~ts conducted byemploying, as catalyst component, the ¢omplex described herein-above and, for comparati~e purposes, the complex ~iC14.CH3COOC2H5~2 are reported iD the Table (tests XIII and XIV) .

-;~ .. , --`~ '~

0.22 ml of TiC14 (2 m. moles) are added dropwise to 20 ml of a 0.5 M solutio~ of MgC12 in ethyl acetate (10 m. moles of MgC12) heated to 50C. The mlxture i9 reacted at 50C for 2 hours, theD the sol~ent is evaporated under vacuum and the grey precipitate i~ dried at 40C.
The X-ray difrra¢tion pattern reveals that such product is a mechanical mixture of MgTiC16.2CH3COOC2H5 and E~ANPIE 11 ; Example 10 i8 repeated using 0.11 ml of pure TiC14 ~ (1 m. mole). ~he resultine pre¢ipltate i9 sub~ected, after; drying, to X-ray analysis and proves to be a mixture Or NgTiC16.
`~ .2CH3C00¢2H5 and Mgpl2.CH3COOC2H5. The titanium content of such mixture i8 ~
The ethylene polymerization te~t carried out using the abo~e-described produ¢t as oatalyti¢ ¢omponent is reported in the Table (te~t XV).
- EXAMP~E 12 Example 10 1~ repeated, but employing 4.4 ml of pure TlC14 (40 m. mole~). Tho precipitate 80 obtained 18 sub~ected, after dr~ing, to anal~sl~ aDd revealed to be a mixture of gTiC16-3CH3Cooc2H5 + [Tlcl4.c~3cooc2H5J2 The ethylene polymerization test ¢onducted by u~ing the produ¢t of this example as catalytlc component i8 reported in the Table (text XVI). --EXAM B 13 ::
2.6 g of MgC12 (27.3 m. moles) are dis~olved ln 50 ml of anhydrous ethylene carbonate at 50G. Separatel~, 3 ml of TlC14 (27.3 m. moles) are disæolved iD 100 ml of anhydrou~
ethylene ¢arbonate at 50C. ~he two solutlons are mixed and :~
allowed to rea¢t for 7 hours at 50C.

, ~, . . . . . . -. . . .
.

1~:)77~60 . ~ powdery yellow precipitate i6 thu~ obtained, .` isolated by hot filtration, and dried at 50C under vacuum.
~he dried yellow powder obtained corre~ponded on ; analysis, to the formula: .
;
,,,, OCE~
y, Mg~icl6 ~ 9co~
s, OCH2 ~ -i ~he ethylene polymerization test conducted by employing i- such complex as catalytic component is reported in the ~able ; 10 (test m I).
. - EXAMPLE 14 :
35 ml of pyridiDe are mixed, dropwise, with 20 ml of a solution of 4.6 g of the ¢omplex Mg~iC16.2CH3COOC2H5 (prepared ac¢ording to Example 9) in ethyl acetate. ~fter a 2-hour3 reaction at 60C, a yellow precipitate i~ obtained: it is filtered and dried by evaporat~on of the solvent. ~he i~olated yellow solid exhibited, on analy~is, a composition ¢orrespondiDg to formula Mg~lC16.6C5H5N. .--~1 ~he ethylene polymerization test conducted by using su¢h complex as catalytic component i~ reported in the ~able ~ (te~t m II).
i , .
EXAMP~E 15 2 g of the ¢omplex Mg~iC16.2CH3COOC2H5 (prepared a8 described in Example 9) are su~pended in 30 ml of POC13. ~he:
suspension i~ reacted for 4 hours at 60C under stirring, then evaporated to dryDess, thus iaolating a yellow powder that, on analysis, iB found to have a compo~ition corresponding to formula Mg~icl6.5pocl3~
~ he ethylene polymerization e~fe¢ted by u8ing such complex as ¢atalyti¢ component is reported in the ~able (test XIX).

.

_ 12 -- -4~ 0 EXAMP~E 16 ID a nitrogeD atmosphere, 3.15 g (17 m. moles) of C13~iOCH3 and 1.62 g (17 m. moles) of anhydrous MgC12 are -~
separately di3solved in, respectively, 40 ml of anhydrous ethyl acetate and in 35 ml of anhydrous ethyl acetate. The two -~
solutions are gathered and heated under stirring to 60C for 5 hours. ~ -The solrent ls e~aporated and the resulting product is dried at 50C under vacuum. A yellow powder is isolated that, on an~lysis, shows a composition corresponding to formula Mg~iC15(0CH3).2CH3COOC2H5 The ethylene polymerization test conducted by using such ¢omple~ as ¢atalyst component is reported in the ~able (test XX).

3.41 g (12.4 m. moles) of C13TiOOC-C6H5 are dissolved in 50 ml of anhydrous ethyl acetate, and the resulting solution is mixed with 24.8 ml of a 0.5 M solution of anh~drou3 MgC12 in ethyl acetate (12,4 m.moles of MgC12). ~he mixture is reacted at 50C for 4 hours under stirring.
After e~aporation of the solvent and drying of the resulting product, a green powder is obtained that, on analysis, is found to have the following compo~ition: MgTiC15(00C-C6H5) .2C~7~COOC2H5 .
The ethylene polymerization test conducted by using such complex as catalytic component is reported in the Table (test XXI).
EXAMP~E 18 26 m. moles of C13TiN(C6H5)2 are dissolved in 150 ml of anhydrous ethyl acetate, and the iesulting solution is added to another solution containing 26 m. moles of anh~drous MgC12 in 52 ml of ethyl acetate. The mixture i~ allowed to react for - 13 _ - - . . .. -: . . .. . .: ~ . . : : -` ~ 1077460 `

4 hours under stirring at room temperature, the~ it i~ evaporated and dried: a brown powder is thus obtained that, on analysis, has the following composition: MgTiC15 ~(C6H5)2].3cH3cooc2 ~
The ethylene polymerization effected by using such complex as catalytic component i9 reported in the Table (te3t XXII).
EXAMPIE 1~
In a nitrogen atmosphere and at a temperature of 60C, 2,12 g of anhydrous MgC12 (22.4 m.mole~) are dissolved in 100 ml o~ deaerated anhydrous n-butyl acetate. 7.6 ml of Ti(O-nC4Hg)4 (22.4 m. moles) are added, always at 60C, to such solution, and the whole is reacted for 4 hours at 60C under E?tirring.
By evaporatio~ of the solvent under vaouu~ at 60C, a colorless pasty produ¢t is isolated; on analy~iæ it has a composition corresponding to formula MgTiC12(0-~C4Hg)4~ ~-.2C~ COOC4Hg.
The ethylee poly~ierization test carried out by using such complex as catalytic ¢amponent iæ reported in the Table (test XXIII).
EXAMP~E 20 ii 1.98 ml (18 m. moles) of TiC14 are added dropwise to a ~? . solution of 3.3 g of NgPr2 (18 m. moles) in 200 ml of anhydrous diethyl ether. A red precipitate forms immediately. It i9 reacted at reflux for 4 hours; then the solvent is evaporated and a brown powder is obtained which, on analysis, has a compo-sition corresponding to formula MgTial4Br2.2(C2H5)20.
The ethylene polymerization test effected by using ~uch complex as catalytic component is reported in the Table (test XXIV).
E~AMPIE 21 1.7 g of anhydrous MnC12 (13.5 m. mole3) are di~solved in 100 ml of anhydrous ethanol. Separately, 2.08 g of TiC13 - 14 _ -' ' ' .

7~460 ' , (13.5 m. mole~) are dissolved in 100 ml of anhydrou~ ethanol.the two solution~ are gathered together and reacted at 25C for 4 hours and at 50C for 8 hours.
The resulting ~ky-blue solutioD is evaporated to dryness, thus obta~ning a grey solid that, on analysis, has a composition correspo~ding to formula MnTiC15.4C2H50H.
~ he ethylene polymerization test condueted by employiDg such complex as catalytic component i3 reported in the Table (test XXV).

5.6 e Of anhydrous MgC12 (59 m. moles) are dissolved, in a nitrogen atmosphere, in 100 ml of anhydrous ethyl acetate.
Similarly, 6.17 g of val3 (39.2 m. moles) are dissolved ~n 150 ml of anhYdrous ethyl acetate.
~ he two solutions are gathered together and rea¢ted under stirring at 60C for 4 hours.
The resulting green solution i9 evaporated to dryness, tb~s obtaining a brown powder which, OD analysis, e~hibits a compositioD corresponding to ~ormula Mg3V2C112.7CH3COOC2H5.
The ethylene polymerization ¢onducted by using such complex - as catalytic component is reported ln the Table (test XXVI). ~-0,203 g of anhydrous Mgpl2 (2.14 m. moles) i~ di~sol~ed in 60 ml of anhydrous tetrahydrofuran. Separatel~, 0.50 g of ZrC14 (2.14 m. moles) is suspended in 100 ml of an~ydrous tetrahydrofuran. The solution is added to the suspension and the whole is reacted at 25C for 6 hour~. It is then evaporated to dryness, thus obtaining a white solid that, on analysis, has a composition corresponding to formula MgZrC16.4C4H80.
The ethylene polymerization te~t conducted by using such complex as catalytic ¢omponent is reported in the Table (test XXVII).

- . .. . .. ..
. .. ~ .
- : . - . -10774~0 - ~XAMPhE 24 0.87 g of anhydrous CaC12 (7.8 m. mole~) i9 dissol~ed, in a nitrogen atmosphere, in 50 ml of deaerated anhydrous C2H50H; analogously, 1.2 g of TiC13 of the HR type (7.8 m, moles) are dissolved in 100 ml o$ deaerated anhydrous C2H50H. The two solutlons are gathered and allowed to react together at 40C, ~or 8 hours.
By evaporation of the solvent under vacuum at 40C, a grey solid i9 isolated. OD analysis, it i~ found to have composition corresponding to formula CaTiC15.4C2H50H.
. , , , -The ethylene polymerization test conducted by using such complex as catalytic component i8 reported in Test XXVIII
of the Table.
EXAMPLæ ? 5 2.97 g of anhydrous CaI2 (10-~. moles) are dissolved, in a nitrogen atmosphere, in 100 ml o$ deaerated anhydrou~
C2H50H; analogously, t.58 g of ~iC13 o$ the HR type (10 m. moles) are di~sol~ed in 60 ml of deaerated anhydrous C2H50H. The two solution~ are gathered and reacted together at 40C for 3 hours.
By evaporation of the solvent under vacuum at 40C, a violet solid i8 lsolated; on analysis, it has a composition corresponding to formula CaTiC13I2.5C2H50H.
The ethylene polymerization test conducted by employing sueh complex as catalytic component i8 reported in Test XXIX of the Table.

2.67 g of the complex Mg~iCl~.4 CH3COOC2H5 (prepared a~ in example 9 with the oDly difference that drying was carried out at 25C instead of at 50~C) were suspended in 30 ml of diethyl malonate. The whol~ wa~ reacted at 60C under stirring for 3 hours; the suspen~lon was then dried by evaporatlon th~s isolating a yellow powder which on analysis showed the composition 7746(~

:: COOC2H5 MgTiC16.3 IH2 The ethylene polymerization te3t conducted by U8iDg ~uch a complex as catalytic compone~t i~ reported on the Table (test XXX).
- ~XAMP~E 27 1.9 g of the complex MgTiC16.4 CH3COOC2H5 (prepared .~ a~ in example 9 with the only difference that drying wa~ carried out at 25C instead of at 50C) were added to 5 ml of anhydrous C~ COOC2~5; subsequently 20 ml of hexamethyl phosphoramide were added dropwise. ~he whole was reacted at 25C uDder ~tirring for 4 hours and then evaporated to drynes~, thus isolating a :
^' yellow powder which on analysls showed the composition MgTiC16, 4 ~(CH3)2 N] 3 The ethylene polymerization test conducted by using such a comilex as catalytic component i~ reported OD the ~able ,1 (test XXXI).

3.6 g of the complex Mg~iC16~4CH3COOC2H5 (prepared as in example 9 with the only difference that drying was ¢arried out at 25C i.n~tead of at 50C) were dissolved iD 30 ml of triphenyl pho~phite. ~he solution w~ reacted under stirring at 25C for 4 hours and the reaction mas~ was evaporated to dryDess, thus isolating an orange-coloured oil wh~ch on analysis showed the compo~itio.n MgliC16.2P(OC6H5)3 ~he ~thylene polymerization test conducted by using such a complex as catalytic compo~ent 1B reported on the ~able (test ~ZXII).
XANP~E 29 0.52 g (5.46 m. moles) of anhydxous Mgpl2 were .. . . . .
.. . . . .
.
.

dlssolved, under nltrogen atmosphere, in 11 ml of anhgdrou~
ethyl acetate and this solution wa~ added to a 8uspeD~ion of 0.65 g (5.46 m. moles) of ~iC12 in 100 ml of anhydrous eth~l acetate. The whole wa~ reacted under stirring at 60C for

6 hours. The re~ulting su~pensio~ was evaporated to dryness, ; thus isolating a black powder which on analysi~ showed the composltion MgT$C14 . 2 CH3COOC2H5 The ethylene polymerization test conducted by uslng such a complex as catalytic component is reported on the Table (test XXXIII).
EXAMP~E 30 Under nitrogen atmosphere were dissolved separately:
1.9 g (20 m. moles) of anhydrous MgC12 in 40 ml of anhydrou~
ethyl acetate; 1.10 ml (10 m. mole~) of ~iC14 in 20 ml o~
anhydrous ethyl acetate; 1.15 ml (10 m. moles) of SnC14 in 20 ml of anh~drous ethyl acetate.
~ he three solutlons were gathered and reacted under stirring at 70C for 4 h~urs. From the reacted solution after concentration and cooling it precipitated a cry~talline yellow product, which ~as isolated by filtration and dried at 25C
under vacuum. The product on analy9is showed the composition Mg4i Snl.5C118-14 CH3COOC2H5 ~ hc ethylene polymerlzatlon test conducted by u~ing ~uch a complex as ¢at~lyti¢ eomponent is reported on the ~able (test XXXIV).
Ethglene ~olYmerlzation in inert ~olvent A suitable amount of one of the catalytic eomplexes prepared in the examples and 1000 ml of deaerated anhydrou~
desulphurized n-heptane are introduced, along with 2 ml of an alkyl aluminum compound, in a nltrogen atmosphere, into a stainle~ ~teel autoclave, having a capacity of 3 liters, , ` 1077460 equipped with an anchor stirrer and heated to the desired temperature.
Hydrogen and ethylene, at the prefixed partial pressures, are added thereto, and the total pressure is kept constant during the whole polymerisatioD by a continuous ethylene feeding.
~ fter a suitable reaction period, polymerizatioD is stopped, the raw polymerization produ¢t is dried. ~he polymer inherent viscosity n_in i8 measured in tetrahydronaphthalene at 135C, usiDg concentrations of 0.25 g of polymer in 100 ml of sol~ent; the yield ls expreseed in erams of polymer obtained per gram of ~i or V or Zr.
~ he results of the ~arious testæ are reported in the i ~able ~tests I to XXXIV).
Ethylene~olymerlzation in eae ~hase 200 g of powdery fully dried polyethyleDe, a suitable amount o~ one Or the ¢atalytic complexes prepared in example3, 30 ml oi deaerated aDhydrous desulphurized n-heptane and 2 m.
moles of a trialkrl aluminum were introduced into a stainless steel 2-litre autocla~e equlpped with an anchor stirrer. A~ter e~aporation o$ the sol~ent by heating at 95C under vacuum 2 atm. o~ hydrogen and ethylene up to a total pressure of 19 atm.
were fed into the autoola~e. The pres~ure wa~ ~ept constant durlng the whole reaot~on tIme by feeding ethylene coDtinuously.
~ fter a ~uitable reaction time the polymerization wa~
stopped and the formed polymer lsolated.
This te~t o~ ethglene polymerization in gas phase i~ reported on the Table (test xxxr).
Prop~lene Polymeri&ation 100 m~ of the catalyti¢ complex prepared in Example 7 and 50 ml of the deaerated, anhydrou~ desulphurized n-heptane are introduced, along with 2 ml of Al(i-C4Hg)3, under a dry _ 19 _ ` 10774~;0 ; argon presæure, into a stainles~ steel 2-liter autoclave, equipped wlth an anchor ~tirrer, heated to 65C and containing hydrogen for a partial pressure of 0.85 atm. as well as 500 g of anhydrous propylene. ~he reaction is stopped after 5 hours, the unpolymerized propylene is dis¢harged and the polymer is taken out from the autoclave, dried and weighed.
~ he result~ of thi~ polymerization test are reported in the Table (text XXXVI~.

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Claims (42)

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. Components of catalysts useful to polymerize olefins, having the general formula MmM'X2mY.nE

wherein:
M = at least one metal selected from the group con-sisting of Mg, Mn and Ca;
m = a number from 0.5 to 2;
M'= at least one metal selected from the group con-sisting of Ti, V and Zr;
X = Cl, Br or I;
Y = one or more atoms or groups, either the same or different from each other, selected from atoms of halogen, atoms of halogen and, contemporaneously, atoms of oxygen, the groups in which R is a hydrocarbon radical; acetylaceto-nate anion, acetylacetonate anion and contempora-neously oxygen atoms; such groups or atoms being present in an amount to satisfy the valence of M';
n = a number from 0.5 m to 20 m;
E = an electron-donor compound selected from the group consisting of (a) esters of organic carboxylic acids;
(b) alcohols; (c) ethers; (d) amines; (e) esters of carbonic acid; (f) nitriles; (g) phosphoramides, esters of phosphoric and phosphorous acid and phos-phorous oxychloride.

2. Components of catalysts according to claim 1, in which 8 portion of Ti, V and/or Zr is replaced by metals selected from the group consisting of Zn, Al, Sn and transition metals in such an amount that the atomic ratio between such metals and Ti, V and/or Zr will range from 0.1:1 to 2:1.

3. Catalytic component according to claim 1, having the formula MgTiC15.2CH3COOC2H5.

4. Catalytic component according to claim 1, having the formula Mg3Ti2Cl12.7CH3COOC2H5.

5. Catalytic component according to claim 1, having the formule MgTiCl5.6C2H5OH.

6. Catalytic component according to claim 1, having the formula MgTiCl5.1OCH3OH.

7. Catalytic component according to claim 1, having the formula MgTiCl5.5 tetrahydrofuran.

8. Catalytic component according to claim 1, having the formula Mg4Ti3AlCl20.12CH3COOC2H5.

9. Catalytic component according to claim 1, having the formula Mg3Ti2Cl12.7C6H5CN.

10. Catalytic component according to claim 1, having the formula Mg3Ti2Cl12.6C6H5COOC2H5.

11. Catalytic component according to claim 1, having the formula MgTiC16.2CH3COOC2H5.

12. Catalytic component according to claim 1, having the formula

13. Catalytic component according to claim 1, having the formula MgTiCl6.6C5H5N.

14. Catalytic component according to claim 1, having the formula MgTiCl6.5POCl3.

15. Catalytic component according to claim 1, having the formula MgTiCl5(OCH3).2CH3COOC2H5.

16. Catalytic component according to claim 1, having the formula MgTiCl5(OOC-C6H5).2CH3COOC2H5.

17. Catalytic component according to claim 1, having the formula MgTiCl5[N(C6H5)2].3CH3COOC2H5.

18. Catalytic component according to claim 1, having the formula MgTiC12(O-C4H9)4.2CH3COOC4H9.

19. Catalytic component according to claim 1, having the formula MgTiCl4Br2.2(C2H5)20.

20. Catalytic component according to claim 1, having the formula MnTiC15.4C2H50H.

21. Catalytic component according to claim 1, having the formula Mg3V2Cl12.7CH3COOC2H5.

22. Catalytic component according to claim 1, having the formula MgZrC16.4 tetrahydrofuran.

23. Catalytic component according to claim 1, having the formula CaTiCl5.4C2H5OH.

24. Catalytio component according to claim 1, having the formula CaTiCl3I2.5C2H5OH.

25. Catalytic component according to claim 1, having the formula MgTiCl6.3CH2(COOC2H5)2.

26. Catalytic component according to claim 1, having the formula MgTiCl6.4[(CH3)2N]3PO.

27. Catalytic component according to claim 1, having the formula MgTiCl6.2P (OC6H5)3.

28. Catalytic component according to claim 1, having the formula MgTiC14.2CH3COOC2H5.

29. Catalytic component according to claim 1, having the formula Mg4TiSn1.5Cl18.14CH3COOC2H5.

30. Components of catalysts for the polymerization of olefins, consisting of a mixture of 99% to 1% by weight of a metal complex according to claim 1 and correspondingly 1% to 99% by weight of an anhydrous magnesium dihalide, the X-ray spectrum of said mixture showing a halo having an intensity peak shifted with respect to the interplanar distance of the most intense line appearing in the spectrum of the magnesium dihalide of normal type.

31. Process for preparing the catalytic components according to claim 1, comprising reacting a compound of formula MX2 in which M represents at least one metal selected from the group consisting of Mg, Mn and Ca and X is chlorine, bromine or iodine, at a temperature ranging from room temperature to about 150°C, with a compound of formula M'Y in which M' represents at least one metal selected from the group consisting of Ti, V and Zr and Y represents one or more atoms or groups which may be the same or different and selected from atoms of both halogen and oxygen, the groups -NR2, -OR, -SR, O-?-R, , in which groups R is a hydrocarbon radical; acetylacetonate anion, both acetylacetonate anion and oxygen atoms, in a solvent which is an electron-donor, and isolating the complex thus formed by crystallization from the solvent, by evaporation of the solvent, or by precipitation with a solvent in which the complex is insoluble.

32. The process according to claim 31, in which the halide MX2 is reacted., at a temperature comprised between room temperature and 150°C, with the compound M'Y in an electron-donor solvent in which the halide MX2 and the compound M'Y are soluble, to form a complex in solution, and the selected electron-donor solvent is then added to the solution of the complex or to the complex after isolation thereof.

33. Process according to claim 31, in which the halide MX2 and the compound M'Y are employed in a MX2/M'Y molar ratio equal to the value of m in the complex to be prepared.

34. Process according to claim 31, in which the halide MX2 and the compound M'Y are employed in a MX2/M'Y molar ratio higher than 2.

35. Process according to claim 31, in which the halide MX2 and the compound M'Y are employed in a M'Y/MX2 molar ratio higher than 2.

36. Catalysts for (co)polymerizing olefins, prepared by mixing (1) a catalyst component having the formula MmM'X2mY.nE
in which M = at least one metal selected from the group consisting of Mg, Mn and Ca;

m = a number from 0.5 to 2;
M'= at least one metal selected from the group consisting of Ti, V and Zr;
X = Cl. Br or I;
Y = one or more atoms or groups, which may be the same or different, and selected from atoms of halogen; atoms of both halogen and, contemporaneously, atoms of oxygen;
the groups -NR2, -OR, -SR, -O-?-R, and , in which R is a hydrocarbon radical; acetylacetonate anion; acetylacetonate ion and, contemporaneously, oxygen atoms; the atoms or groups Y being present in an amount corresponding to the valence of M';
n = a number from 0.5 m to 20 m; and E = an electron-donor compound selected from the group consisting of (a) esters of organic carboxylic acids; (b) alcohols;
(c) ethers; (d) amines; (e) esters of carbonic acid; (f) nitriles; (g) phosphor-amides, esters of phosphoric and phosphorous acid and phosphorus oxychloride;
with (2) an organometallic compound of a metal belonging to one of Groups I, II or III of the Mendelyeev Periodic Table.

37. Catalysts for (co)polymerizing olefins, prepared by mixing:
(1) a catalytic component as defined in claim 2, and (2) an organometallic compound of a metal belonging to one of Groups I, II or III of the Mendelyeev Periodic Table.

38. Catalysts for (co)polymerizing olefins, prepared by mixing:
(1) a catalytic component as defined in claim 30, and (2) an organometallic compound of a metal belonging to one of Groups I, II or III of the Mendelyeev Periodic Table.

39. Process for polymerizing or copolymerizing olefins, which comprises effecting the polymerization or copolymerization in the presence of a catalyst according to claim 36.

40. Process for polymerizing or copolymerizing olefins, which comprises effecting the polymerization or copolymerization in the presence of a catalyst according to claim 37.

41. Process for polymerizing or copolymerizing olefins, which comprises effecting the polymerization or copolymerization in the presence of a catalyst according to claim 38.

42. Process for polymerizing ethylene in gas phase, which comprises effecting the polymerization in the presence of a catalyst prepared by mixing:
(1) a catalyst component according to claim 1, and (2) an aluminum trialkyl compound.