Telechelic polyolefin and preparation thereof

1. A process for preparing a telechelic polyolefin of formula (I):

CH 2 ═CH—(CH 2 ) p -A-Z  (I)

wherein:

A represents a (co)polymer comprising at least 95 mol % of (CH 2 —CH 2 ) units;

Z is selected from the group consisting of halogens; thiols and their derivatives; azides; amines; alcohols; the carboxylic acid function; isocyanates; silanes; phosphorous derivatives; dithioesters; dithiocarbamates; dithiocarbonates; trithiocarbonates; alkoxyamines; the vinyl function; dienes; and the group -A-(CH 2 ) p —CH═CH 2 ; and

p is a whole number between 1 and 20,

said process comprising the following steps:

preparing a compound of formula (II):

Y(A-(CH 2 ) p —CH═CH 2 ) m   (II)

wherein m is 2 or 3; and

when m=2, Y is an alkaline earth metal; and

when m=3, Y is an element of group 13; and

cleaving the bond between Y and A-(CH 2 ) p —CH═CH 2 , and functionalizing A-(CH 2 ) p —CH═CH 2 with Z.

2. A process according to claim 1 , wherein the preparing the compound of formula (II) is achieved in the presence of a transition metal or lanthanide complex, and a transfer agent of formula (III):

Y((CH 2 ) p —CH═CH 2 ) m   (III).

3. A process according to claim 2 , wherein the transition metal or lanthanide complex is a metallocene selected from the group consisting of compounds of which the formula contains the base structure: (Cp 1 )(Cp 2 )M or E(Cp 1 )(Cp 2 )M;

M being a group 3 or 4 metal, or a lanthanide; and

Cp 1 , Cp 2 being cyclopentadienyl, fluorenyl or indenyl groups or those groups featuring additional substituents;

E being a bridge between the Cp 1 and Cp 2 ligands, of the formula M′R 1 R 2 , M′ being a group 14 element, and R 1 and R 2 being alkyl or aryl groups having 1 to 20 carbon atoms.

4. A process according to claim 3 , wherein the complex is a metallocene of the formula (C 5 Me 5 ) 2 MX 2 Li(OEt 2 ) 2 , M being a group 3 metal or lanthanide and X being a halogen.

5. A process according to claim 4 , wherein M is a lanthanide.

6. A process according to claim 2 , wherein the telechelic polyolefin is represented by the formula CH 2 ═CH—(CH 2 ) p —(CH 2 —CH 2 ) n —I, I being an iodine atom, p being a whole number between 6 and 9, and n being a whole number between 17 and 360.

7. A process according to claim 1 , wherein the functionalizing step with Z comprises the addition of a compound selected from the group consisting of iodine I 2 , sulfur S 8 and tetraethylthiuram disulfide.

8. A process according to claim 1 , wherein the functionalizing step with Z is an oxidative coupling when Z=-A-(CH 2 ) p —CH═CH 2 .

9. A process according to claim 1 , further comprising, subsequent to the functionalizing with Z, modifying at least one of the chain-ends of the telechelic polyolefin by reaction of the vinyl function and/or of the Z group.

10. A process according to claim 1 , wherein, when m=2, Y is magnesium or zinc, and when m=3, Y is aluminum.

11. A process according to claim 1 , wherein p is a whole number between 6 and 9.

12. A process according to claim 1 , wherein the telechelic polyolefin is represented by the formula CH 2 ═CH—(CH 2 ) p —(CH 2 —CH 2 ) n —I, I being an iodine atom, p being a whole number between 6 and 9, and n being a whole number between 17 and 360.

13. A telechelic polyolefin of formula (I):

CH 2 ═CH—(CH 2 ) p -A-Z  (I)

wherein:

A represents a (co)polymer comprising at least 95 mol % of (CH 2 —CH 2 ) units;

Z is selected from the group consisting of halogens; thiols and their derivatives; azides; amines; alcohols; the carboxylic acid function; isocyanates; silanes; phosphorous derivatives; dithioesters; dithiocarbamates; dithiocarbonates; trithiocarbonates; alkoxyamines; and dienes; and

p is a whole number between 1 and 20.

14. A telechelic polyolefin according to claim 13 , wherein the CH 2 ═CH—(CH 2 ) p — group of formula (I) originates from a transfer agent of formula Y((CH 2 ) p —CH═CH 2 ) m , wherein m is 2 or 3; and when m=2, Y is an alkaline earth metal; and when m=3, Y is an element of group 13.

15. A telechelic polyolefin according to claim 13 , wherein A is a linear polyethylene of formula (CH 2 —CH 2 ) n , n being a whole number between 7 and 3600.

16. A telechelic polyolefin according to claim 13 , wherein the telechelic polyolefin is represented by the formula CH 2 ═CH—(CH 2 ) p —(CH 2 —CH 2 ) n —I, I being an iodine atom, p being a whole number between 6 and 9, and n being a whole number between 17 and 360.

17. A telechelic polyolefin according to claim 13 wherein p is a whole number between 6 and 9.