Low-viscosity solutions of alkaline-earth metal alkoxides in aprotic solvents, method for the production of same and use for the production of ziegler-natta catalysts

1. A method for synthesis of alkaline earth alkoxide compounds M(OCH 2 R 6 ) 2-a-b (OR 7 ) a [O(CHR 8 ) n OR 9 ] b in mixture with an alkaline earth metal alkyl compound M(R 10 R 11 ), the method comprising

(A) mixing one or more alkaline earth metals, an aprotic solvent, one or more alkyl aluminum compounds, and one or more alcohols at a temperature in the range of 0° C. and 180° C. to produce a mixture comprising the alkaline earth alkoxide compounds M(OCH 2 R 6 ) 2-a-b (OR 7 ) a [O(CHR 8 ) n OR 9 ] b ;

wherein:

(i) M is an alkaline earth metal selected from the group consisting of Mg, Ca, Ba, and Sr;

(ii) OCH 2 R 6 is an alkoxide radical having 3 to 40 carbon atoms with a branch in position 2 relative to the O function;

(iii) R 7 is an alkyl radical having 2 to 15 carbon atoms, which is either linear or has a branch in ≥position 3 relative to the O function;

(iv) R 8 is an alkyl radical having 1 to 6 carbon atoms, which is either linear or has a branch at ≥position 3 relative to the O function;

(v) R 9 is an alkyl radical having 2 to 15 carbon atoms, which is either linear or has a branch;

(vi) R 10 and R 11 each are an alkyl radical having 1 to 15 carbon atoms;

(vii) n is an integer from 1 to 4;

(viii) a+b≤2 wherein a and b each have a value of 0 to 2; and

(B) adding one or more alkaline metal alkyl compounds M(R 10 R 11 ) to the mixture comprising the alkaline earth alkoxide compounds M(OCH 2 R 6 ) 2-a-b (OR 7 ) a [O(CHR 8 ) n OR 9 ] b , wherein the molar ratio of M(OCH 2 R 6 ) 2-a-b (OR 7 ) a [O(CHR 8 ) n OR 9 ] b to M(R 10 R 11 ) is from 99.5:0.5 to 60:40.

2. The method according to claim 1 wherein the one or more alkyl aluminum compounds are selected from the group consisting of alkyl aluminum compounds, alkylalkoxy aluminum compounds, alkyl aluminum halide compounds, alkyl aluminum hydride compounds, wherein the aluminum concentration based on the dissolved alkaline earth metal is in the range of 0 mol % to about 20 mol %.

3. The method according claim 2 , wherein the aluminum concentration based on the dissolved alkaline earth metal is in the range of 0.2 mol % to about 15 mol %.

4. The method according claim 2 , wherein the aluminum concentration based on the dissolved alkaline earth metal is in the range of 0.5 mol % to about 4 mol %.

5. The method according to claim 2 wherein in step (B) the molar ratio of M(OCH 2 R 6 ) 2-a-b (OR 7 ) a [O(CHR 8 ) n OR 9 ] b to M(R 10 R 11 ) is from 99:1 to 70:30.

6. The method according to claim 2 wherein in step (B) the molar ratio of M(OCH 2 R 6 ) 2-a-b (OR 7 ) a [O(CHR 8 ) n OR 9 ] b to M(R 10 R 11 ) is from 95:5 to 80:20.

7. The method according to claim 2 , wherein step (B) occurs after the end of the reaction in step (A).

8. The method according to claim 2 wherein in step (A) half of the molar ratio of the total number of moles of all alcohols to the alkaline earth metal alkyl compound is from 99.5:0.5 to 60:40.

9. The method according to claim 2 wherein in step (A) half of the molar ratio of the total number of moles of all alcohols to the alkaline earth metal alkyl compound is from 99:1 to 70:30.

10. The method according to claim 2 wherein in step (A) half of the molar ratio of the total number of moles of all alcohols to the alkaline earth metal alkyl compound is from 99:5 to 80:20.

11. The method according to claim 1 , wherein the aprotic solvent is either (i) an aliphatic solvent selected from the group consisting of cyclohexane, methyl cyclohexane, hexane, heptane, octane, nonane, decane, dodecane, decalin and gasoline fractions; or (ii) an aromatic solvent selected from the group consisting of benzene, toluene, ethylbenzene, xylenes and cumene.

12. The method according to claim 1 , wherein the one or more alcohols are selected from the group of HOCH 2 R 6 , HOR 7 , HO(CHR 8 ) n OR 9 , and any combination of two or more of the foregoing,

wherein HO(CHR 8 ) n OR 9 is selected from the group consisting of 2-ethoxyethanol, 3-ethoxy-1-propanol, 3-ethoxy-1-butanol, 2-(2-ethylhexoxy)ethanol, 2-butoxyethanol, 2-hexyloxyethanol, 1,3-propylene glycol monobutyl ether, and any combination of two or more of the foregoing;

wherein HOCH 2 R 6 is branched in position 2 and is selected from the group consisting of isobutanol, 2-methyl-1-pentanol, 2-ethyl-1-butanol, 2-ethyl-1-pentanol, 2-ethyl-4-methyl-1-pentanol, 2-propyl-1-heptanol, 2-methyl-1-hexanol, 2-ethylhexanol and 2-ethyl-5-methyl-1-octanol, and any combination of two or more of the foregoing; and

wherein HOR 7 is selected from the group consisting of ethanol, propanol, butanol, pentanol, hexanol, octanol, decanol, dodecanol, 3-methylbutan-1-ol, and any combination of two or more of the foregoing.

13. The method according to claim 1 , wherein in step (A) the reaction conditions comprise a temperature in the range of about 40° C. and 140° C.

14. The method according to claim 1 , wherein in step (A) the reaction conditions comprise a temperature that is at the boiling point of the aprotic solvent.