US 11,746,167 B2
Process for the preparation of polyisoprene with a mainly alternating cis-1,4- alt-3,4 structure in the presence of a catalytic system comprising a pyridyl iron complex
Giovanni Ricci, Parma (IT); Anna Sommazzi, Novara (IT); Guido Pampaloni, Pontedera (IT); Giuseppe Leone, Milan (IT); and Francesco Masi, Sant'angleo Lodigiano (IT)
Assigned to Versalis S.P.A., Milanese (IT)
Appl. No. 16/962,056
Filed by VERSALIS S.P.A., San Donato Milanese (IT)
PCT Filed Jan. 16, 2019, PCT No. PCT/IB2019/050333
§ 371(c)(1), (2) Date Jul. 14, 2020,
PCT Pub. No. WO2019/142108, PCT Pub. Date Jul. 25, 2019.
Claims priority of application No. 102018000001149 (IT), filed on Jan. 17, 2018.
Prior Publication US 2020/0369805 A1, Nov. 26, 2020
Int. Cl. C08F 136/08 (2006.01); A43B 1/10 (2006.01); B60C 1/00 (2006.01); C07F 15/02 (2006.01)
CPC C08F 136/08 (2013.01) [A43B 1/10 (2013.01); B60C 1/0016 (2013.01); C07F 15/025 (2013.01)] 17 Claims
OG exemplary drawing
 
1. A process for the preparation of polyisoprene with a mainly alternating cis-1,4-alt-3,4 structure the process comprising:
polymerizing isoprene in the presence of a catalytic system, the system comprising:
(a) at least one pyridyl iron complex having general formula (I):

OG Complex Work Unit Chemistry
wherein:
R1 is selected from linear or branched C1-C20 alkyl groups, optionally substituted cycloalkyl groups, and optionally substituted aryl groups;
R2 is selected from linear or branched C1-C10 alkyl groups;
X, mutually identical or different, represents a halogen atom; or X is selected from linear or branched C1-C20 alkyl groups, —OCOR3 groups and —OR3 groups wherein R3 is selected from linear or branched C1-C20 alkyl groups;
n is 2 or 3;
(b) at least one co-catalyst selected from (b1) aluminoxanes having general formula (II):
(R4)2—Al—O—[—Al(R5)—O—]m—Al—(R6)2  (II)
wherein R4, R5 and R6, mutually identical or different, represent a hydrogen atom or a halogen atom; or R4, R5 and R6 are selected from linear or branched C1-C20 alkyl groups, cycloalkyl groups, and aryl groups, the groups being optionally substituted with one or more silicon or germanium atoms; and m is an integer ranging from 0 to 1000;
(b2) aluminum compounds having general formula (III):
Al(R7)(R8)(R9)  (III)
wherein R7 represents a hydrogen atom, or is selected from linear or branched C1-C20 alkyl groups, cycloalkyl groups, aryl groups, alkylaryl groups, arylalkyl groups, alkoxy groups; R8 and R9, mutually identical or different, are selected from linear or branched C1-C20 alkyl groups, cycloalkyl groups, aryl groups, alkylaryl groups, and arylalkyl groups;
wherein the molar ratio between aluminum present in the co-catalyst and iron present in the pyridyl iron complex having general formula (I) ranges from 5 to 60.