Stereoregular diblock polybutadienes having a 1,4-cis/syndiotactic 1,2 structure from stereospecific polymerization

Patent metadata

Field	Value
Publication number	US-2016264706-A1
Application number	US-201415032207-A
Country	US
Kind code	A1
Filing date	Nov 3, 2014
Priority date	Nov 5, 2013
Publication date	Sep 15, 2016
Grant date	—

Abstract

Stereoregular diblock polybutadiene composed of a polybutadiene block having a 1,4-cis structure and a polybutadiene block having a syndiotactic 1,2 structure. Said stereoregular diblock polybutadiene can be advantageously used in both the footwear industry (for example, in the production of soles for shoes) and in the production of tires for motor vehicles and/or trucks.

First claim

1 . A stereoregular diblock polybutadiene composed of a polybutadiene block having a 1,4-cis structure and a polybutadiene block having a 1,2 syndiotactic structure, having the following formula (I):
PB 1 —PB 2   (I)

wherein:
PB 1 corresponds to the polybutadiene block having a 1,4-cis structure;
PB 2 corresponds to the polybutadiene block having a 1,2 syndiotactic structure;

essentially free of 1,4-trans units.

2 . The stereoregular diblock polybutadiene according to claim 1 , wherein said stereoregular diblock polybutadiene has the following characteristics:
upon infrared analysis (FT-IR), bands typical of the 1,4-cis and 1,2 sequences centered at 737 cm −1 and at 911 cm −1 , respectively; upon 13 C-NMR analysis; signals characteristic of the junctions between the polybutadiene block having a 1,4-cis structure and the polybutadiene block having a 1,2 structure at 30.7 ppm, at 25.5 ppm and at 41.6 ppm.

3 . The stereoregular diblock polybutadiene according to claim 1 , wherein, in said stereoregular diblock polybutadiene:
the block having a 1,4-cis structure has a glass transition temperature (TO lower than or equal to −100° C., a melting point (T m ) lower than or equal to −2° C., and a crystallization temperature (T c ) lower than or equal to −25° C., the block having a 1,2 syndiotactic structure has a glass transition temperature (T g ) lower than or equal to −10° C., a melting point (T m ) higher than or equal to 70° C., and a crystallization temperature (T c ) higher than or equal to 55° C.

4 . The stereoregular diblock polybutadiene according to claim 1 , wherein said stereoregular diblock polybutadiene has a polydispersion index (PDI) corresponding to a M w /M n ratio (M w =weight average molecular weight; M n =number average molecular weight) ranging from 1.9 to 2.2.

5 . The stereoregular diblock polybutadiene according to claim 1 , wherein in said stereoregular diblock polybutadiene, the polybutadiene block having a 1,4-cis structure is amorphous, at room temperature under quiescent conditions (i.e. not subjected to stress), and has a 1,4-cis content higher than or equal to 96% molar, with respect to the total molar quantity of butadiene units present in said polybutadiene block having a 1,4-cis structure.

6 . The stereoregular diblock polybutadiene according to claim 1 , wherein in said stereoregular diblock polybutadiene, the polybutadiene block having a 1,2 syndiotactic structure has a content of syndiotactic triads [(rr) %] higher than or equal to 15%.

7 . The stereoregular diblock polybutadiene according to claim 1 , wherein in said stereoregular diblock polybutadiene, the 1,4-cis/1,2 molar ratio ranges from 15:85 to 80:20.

8 . The stereoregular diblock polybutadiene according to claim 1 , wherein said stereoregular diblock polybutadiene has a weight average molecular weight (M w ) ranging from 100,000 g/mol to 800,000 g/mol.

9 . A process for the preparation of a stereoregular diblock polybutadiene according to claim 1 , comprising:
subjecting 1,3-butadiene to total or partial stereospecific polymerization in the presence of a catalytic system comprising at least one complex of cobalt including at least one imine nitrogen, in order to obtain polybutadiene with a 1,4-cis living structure; adding at least one monodentate aromatic phosphine and optionally 1,3-butadiene, and continuing said stereospecific polymerization, in order to obtain said stereoregular diblock polybutadiene composed of a polybutadiene block having a 1,4-cis structure and a polybutadiene block having a 1,2 syndiotactic structure.

10 . The process according to claim 9 , wherein said cobalt complex including at least one imine nitrogen is selected from bis-imine complexes of cobalt having general formula (I):

wherein:
n is 0 or 1;
Y represents a group —CR′R″ wherein R′ and R″, the same or different, represent a hydrogen atom; or a linear or branched C 1 -C 20 alkyl group; or a divalent aromatic group optionally substituted;
R 1 and R 2 , the same or different, represent a hydrogen atom; or they are selected from a linear or branched C 1 -C 20 alkyl group, optionally halogenated, cycloalkyl groups optionally substituted; or R 1 and R 2 can be optionally bound to each other to form, together with the other atoms to which they are bound, a cycle containing from 4 to 6 carbon atoms, saturated, unsaturated, or aromatic, optionally substituted with linear or branched C 1 -C 20 , said cycle optionally containing heteroatoms such as oxygen, sulfur, nitrogen, silicon, phosphorous, selenium;
R 3 and R 4 , the same or different, represent a hydrogen atom; or they are selected from a linear or branched C 1 -C 20 alkyl group optionally halogenated, cycloalkyl groups optionally substituted; aryl groups optionally substituted;
or R 2 and R 4 can be optionally bound to each other to form, together with the other atoms to which they are bound, a cycle containing from 3 to 6 carbon atoms, saturated, unsaturated, or aromatic, optionally substituted with linear or branched C 1 -C 20 alkyl groups, said cycle optionally containing other heteroatoms such as oxygen, sulfur, nitrogen, silicon, phosphorous, selenium;
or R 1 and R 3 can be optionally bound to each other to form, together with the other atoms to which they are bound, a cycle containing from 3 to 6 carbon atoms, saturated, unsaturated, or aromatic, optionally substituted with linear or branched C 1 -C 20 alkyl groups, said cycle optionally containing other heteroatoms such as oxygen, sulfur, nitrogen, silicon, phosphorous, selenium;
X 1 and X 2 , the same or different, represent a halogen atom such as chlorine, bromine, iodine; or they are selected from linear or branched C 1 -C 20 alkyl groups, —OCOR 5 groups or —OR 5 groups wherein R 5 is selected from linear or branched C 1 -C 20 alkyl groups.

11 . The process according to claim 9 , wherein said cobalt complex including at least one imine nitrogen is selected from oxo-nitrogenated complexes of cobalt having general formula (Ia):

wherein:
R 1 and R 2 , the same or different, represent a hydrogen atom; or they are selected from linear or branched C 1 -C 20 alkyl groups, optionally halogenated, cycloalkyl groups optionally substituted, aryl groups optionally substituted;
R 3 represents a hydrogen atom, or it is selected from linear or branched C 1 -C 20 alkyl groups optionally halogenated, cycloalkyl groups optionally substituted; aryl groups optionally substituted; or R 3 represents a ketoimine group having formula:

wherein R′ and R″, the same or different, represent a hydrogen atom, or they are selected from linear or branched C 1 -C 20 alkyl groups, cycloalkyl groups optionally substituted, aryl groups optionally substituted;
X 1 and X 2 , the same or different, represent a halogen atom such as chlorine, bromine, iodine; or they are selected from linear or branched C 1 -C 20 alkyl groups, —OCOR 4 groups or —OR 4 groups wherein R 4 is selected from linear or branched C 1 -C 20 alkyl groups.

12 . The process according to claim 9 , wherein said cobalt complex including at least one imine nitrogen is selected from oxo-nitrogenated complexes of cobalt having general formula (Ib):

wherei

Assignees

• Versalis Spa

Inventors

• Masi Francesco
• Sommazzi Anna
• Ricci Giovanni
• Leone Giuseppe
• Coppola Salvatore

Classifications

• C08F4/7042

  NNN · CPC title

• C08F36/06

  Butadiene · CPC title

• C08F4/7008

  NO · CPC title

• C08F4/7044

  NNO · CPC title

• C08F295/00 Primary

  Macromolecular compounds obtained by polymerisation using successively different catalyst types without deactivating the intermediate polymer · CPC title