Methods for modulated degenerative transfer living polymerization and isotactic-atactic stereoblock and stereogradient poly(olefins) thereby

1. A method of producing a monomodal, multiblock, stereoblock polyolefin having substantially uniform microstructure comprising:

(a) contacting a Ziegler-Natta pre-catalyst with a co-catalyst and an olefin to polymerize said olefin and form a first stereoblock;

(b) adding a methyl donator that changes the stereoregularity of the polymerization, wherein the methyl donator does not catalyze the polymerization of an olefin; and

(c) polymerizing said olefin to form a second stereoblock;

whereby a monomodal, multiblock, stereoblock polyolefin is produced.

2. The method of claim 1 , further comprising quenching the polymerization by adding a protic solvent.

3. The method of claim 1 , wherein said Ziegler-Natta pre-catalyst catalyst has the formula:

wherein the dotted lines indicate a delocalized bond;

M is Ti, Zr or Hf;

each R 1 is independently hydrogen, alkyl, cycloalkyl, optionally substituted phenyl or two adjacent R 1 form an aromatic ring;

R 2 , R 3 and R 4 are independently alkyl, cycloalkyl, Si(alkyl) 3 , Si(aryl) 3 , optionally substituted phenyl, or alkylphenyl;

each R 5 is halo, alkyl, cycloalkyl, aryl or arylalkyl; and

said optional substituents on phenyl are amino, hydroxy, alkoxy, amide, aryl, alkyl, halo, ketone, ester, —SO 3 H, aldehyde, carboxylic acid, cyano, nitro and ammonium.

4. The method of claim 3 , wherein said Ziegler-Natta pre-catalyst is 1,2,3,4,5-pentamethylcyclopentadienyl dimethyl zirconium (N-ethyl-N- t butyl-2-methyl)amidinate.

5. The method of claim 1 , wherein said co-catalyst is an MAO-type co-catalyst or boron-containing co-catalyst.

6. The method of claim 5 , wherein said co-catalyst has one of the formulae:

[A] + [BR 6 4 ] − or BR 6 3

wherein A + is Si(R 7 ) 3 , a cationic Lewis acid or a cationic Brønsted acid;

B is the element boron;

R 6 is alkyl or optionally substituted phenyl;

each R 7 is independently selected from alkyl and optionally substituted phenyl; and

said optional substituents on phenyl are alkoxy, amino, amide, aryl, alkyl, halo, ketone, ester, —SO 3 H, aldehyde, carboxylic acid, cyano, nitro and ammonium.

7. The method of claim 6 , wherein said co-catalyst is [PhNMe 2 H][B(C 6 F 5 ) 4 ].

8. The method of claim 1 , wherein said olefin is ethene, propene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, styrene, alpha-methyl styrene, butadiene, isoprene, acrylonitrile, methyl acrylate, methyl methacrylate, vinyl acetate, vinyl chloride, vinyl fluoride, vinylidene chloride, N-vinyl pyrrolidone, 3-methylbutene, 3-methyl-1-pentene, vinylcyclohexane, vinylcyclobutane, vinylcyclopentane, vinylcyclooctane, 1-decene, enantiomerically pure β-citronellene, 3,5,5-trimethyl-1-hexene, 4-methyl-1-pentene; a non-conjugated diene having the formula:

wherein X is CH 2 , CO, N(R 13 ), O or S;

R 12 and R 13 are independently H, alkyl or phenyl; and

n and m are each independently an integer from 0-5;

oligomers thereof, polymers thereof or mixtures thereof.

9. The method of claim 1 , wherein (a) comprises contacting said Ziegler-Natta pre-catalyst with about a stoichiometric amount of co-catalyst.

10. The method of claim 9 , wherein said first stereoblock is an isotactic polyolefin stereoblock.

11. The method of claim 1 wherein said methyl donator changes the polymerization from a stereoregular to a non-stereoregular polymerization.

12. The method of claim 1 , wherein said methyl donator has the formula:

wherein the dotted lines indicate a delocalized bond;

M is Ti, Zr or Hf;

each R 1 is independently alkyl, cycloalkyl, optionally substituted phenyl or two adjacent R 1 form an aromatic ring;

R 2 , R 3 and R 4 are independently bulky alkyl, cycloalkyl, Si(alkyl) 3 , Si(aryl) 3 , optionally substituted phenyl, or alkylphenyl;

each R 5 is methyl; and

said optional substituents on phenyl are amino, hydroxy, alkoxy, amide, aryl, alkyl, halo, ketone, ester, —SO 3 H, aldehyde, carboxylic acid, cyano, nitro and ammonium.

13. The method of claim 12 , wherein

R 1 is methyl;

one of R 2 and R 3 is tert-butyl;

R 4 is tert-butyl; and

R 5 is methyl.

14. The method of claim 13 , wherein said methyl donator is 1,2,3,4,5-pentamethylcyclopentadienyl dimethyl zirconium (N-ethyl-N- t butyl-2- t butyl)amidinate.

15. The method of claim 1 , wherein said methyl donator is added in an amount of about 10-50 mole % of said Ziegler Natta pre-catalyst.

16. The method of claim 15 , wherein said second stereoblock is an atactic stereoblock.

17. The method of claim 16 , wherein said multiblock, stereoblock polyolefin comprises an isotactic-atactic microstructure.

18. The method of claim 1 , wherein (c) further comprises:

adding a second olefin to said polymerization and polymerizing said second olefin to form said second stereoblock.

19. The method of claim 1 , further comprising after (c):

(d) adding co-catalyst to change the stereoregularity of the polymerization; and

(e) polymerizing said olefin to form a third stereoblock.

20. The method of claim 19 , wherein said co-catalyst is added in sufficient amount to form an isotactic third stereoblock.

21. The method of claim 20 , wherein said stereoblock polyolefin comprises an isotactic-atactic-isotactic microstructure.

22. The method of claim 21 , wherein said stereoblock polyolefin is isotactic-atactic-isotactic polypropylene.

23. The method of claim 19 , wherein (e) further comprises:

adding a third olefin to said polymerization and polymerizing said third olefin to form said third stereoblock.

24. The method of claim 23 , wherein said olefin in (a) and said third olefin are the same.

25. The method of claim 19 , wherein (b) through (e) are repeated one, two, three, four or five times.

26. The method of claim 25 , wherein (b) through (e) are repeated one time to form a pentablock stereoblock polyolefin comprising an isotactic-atactic-isotactic-atactic-isotactic microstructure.

27. The method of claim 26 , wherein said stereoblock polyolefin is iso-poly(octene)-a-poly(hexene)-iso-poly(octene)-a-poly(hexene)-iso-poly(octene).