Hairy polymeric nanoparticles with first and second shell block polymer arms

Patent metadata

Field	Value
Publication number	US-9493601-B2
Application number	US-201514746142-A
Country	US
Kind code	B2
Filing date	Jun 22, 2015
Priority date	Apr 3, 2009
Publication date	Nov 15, 2016
Grant date	Nov 15, 2016

Abstract

Compositions and methods are included for preparing a hairy polymeric nanoparticle including first and second shell block polymer arms are at least partially phase-separated and surround a polymeric core. One type of polymeric arm can have a greater polarity than the other type(s) of polymeric arms. A rubber composition including the hairy nanoparticles is also provided.

First claim

It is claimed:

1. A process for preparing multi-armed nanoparticles, said process comprising:
(a) polymerizing a first shell block monomer into a plurality of first shell block polymer arms;
(b) polymerizing a second shell block monomer into a plurality of second shell block polymer arms;
(c) combining the first shell block polymer arms and the second shell block polymer arms with a core monomer and polymerizing the core monomer onto the first shell block polymer arms and the second shell block polymer arms, wherein monomer residues of the first shell block polymer arms are different than monomer residues of the second shell block polymer arms;
wherein the first shell block polymer arm includes a functional group, wherein the functional group includes a heterocyclic aromatic compound;
wherein at least one of steps (a), (b), and (c) is performed by solution polymerization.

2. The process of claim 1 , wherein said polymerizing of steps (a), (b), and (c) is performed by living anionic polymerization.

3. The process of claim 1 , wherein the block polymer arms are formed into nanoparticles by micelle assembly and subsequent crosslinking of the core block polymer with a cross-linking agent.

4. The process of claim 1 , further comprising, after step (c), wherein the functional group is added to reactive functionalities on the first block polymer arms, wherein the second block polymer arms are substantially exclusive of reactive functionalities.

5. The process of claim 1 , wherein the first shell block polymer arm and the second shell block polymer arm phase separate in a solid state blend and are miscible in a hexane solution.

6. The process of claim 1 , wherein said first shell block polymer arms comprise one or more monomer residues derived from a conjugated diene; and said second shell block polymer arms comprise one or more monomer residues derived from an alkenyl substituted aromatic compound.

7. The process of claim 1 , wherein the first shell block polymer arm includes a functional group selected from the group consisting of a heterocyclic aromatic compound or styrene substituted with a heteroatomic group.

8. The process of claim 1 , wherein said first shell block polymer arms each comprise at least one monomer residue having at least one polar moiety with a dipole moment of at least 0.5 D.

9. The process of claim 1 , wherein the second shell block polymer arms are substantially exclusive of reactive functionalities.

10. The process of claim 1 , wherein said nanoparticle has a ratio of said first shell block polymer arms to said second shell block polymer arms in the range of from about 0.5:1 to about 2:1.

11. The process of claim 1 , wherein the core is at least 3% by weight of the nanoparticle.

12. A living anionic polymerization process for preparing Janus nanoparticles, said process comprising:
(a) polymerizing a first shell block monomer into a plurality of first shell block polymer arms;
(b) polymerizing at least one core monomer onto said first shell block polymer arms;
(c) cross-linking the core monomer residues;
(d) polymerizing a second shell block monomer onto said core block polymer to form a plurality of second shell block polymer arms; and
(e) allowing at least partial phase separation between said first and second shell block polymer arms, thereby forming said Janus nanoparticles;
wherein the first shell block polymer arm includes a functional group, wherein the functional group includes a heterocyclic aromatic compound;
wherein at least one of steps (a), (b), and (c) is performed by solution polymerization.

13. A process for preparing a rubber composition including multi-armed nanoparticles, said process comprising:
polymerizing the multi-armed nanoparticle and mixing the multi-armed nanoparticle into a rubber composition;
wherein polymerizing the multi-armed nanoparticle comprises:
(a) polymerizing a first shell block monomer into a plurality of first shell block polymer arms;
(b) polymerizing a second shell block monomer into a plurality of second shell block polymer arms;
(c) combining the first shell block polymer arms and the second shell block polymer arms with a core monomer and polymerizing the core monomer onto the first shell block polymer arms and the second shell block polymer arms, wherein monomer residues of the first shell block polymer arms are different than monomer residues of the second shell block polymer arms;
wherein the first shell block polymer arm includes a functional group, wherein the functional group is selected from the group consisting of heterocyclic aromatic compound, styrene substituted with a heteroatomic group, a hydroxyl functional group, an acyl functional group, an anhydride functional group, an epoxy functional group, and a silane functional group; wherein at least one of steps (a), (b), and (c) is performed by solution polymerization;
wherein the rubber composition comprises a first matrix polymer and a second matrix polymer, and the first and second matrix polymer and the first and second shell block polymer arms are selected from the following combinations:
the first matrix polymer is a high 1,4 polyisoprene or natural rubber and the second matrix polymer is a high 1,4 polybutadiene, the first shell block polymer arm is a high 1,4 polyisoprene; or a 1,2 polybutadiene, and the second shell block polymer arm is a high 1,4 polybutadiene,
the first matrix polymer is high 1,2 polybutadiene and the second matrix polymer is a high 1,4 polybutadiene, the first shell block polymer arm is a high 1,2 polybutadiene or a 1,4 polyisoprene, and the second shell block polymer arm is a high 1,4 polybutadiene,
the first matrix polymer is high 1,4 polybutadiene and the second matrix polymer is poly(styrene-co-butadiene), the first shell block polymer arm is a high 1,4 polybutadiene, and the second shell block polymer is a poly(styrene-co-butadiene);
the first matrix polymer is high 1,4 polyisoprene or natural rubber, the second matrix polymer is poly(styrene-co-butadiene), the first shell block polymer arm is high 1,4 polyisoprene, and the second shell block polymer is poly(styrene-co-butadiene);
wherein the first shell block polymer arm includes the functional group.

14. The process of claim 13 , further comprising mixing a filler into the rubber composition, wherein the filler is selected from the group consisting of silica, carbon black, and combinations thereof.

15. The process of claim 13 , further comprising forming the rubber composition into a tire component.

16. The process of claim 13 , wherein the rubber comprises a rubber polymer, and an Mn of the first or second shell block polymer is more than 50% of an Mn of the rubber polymer.

17. The process of claim 13 , wherein said rubber composition has a Mooney viscosity (ML 1+4 ) of less than 70 MU after curing and a storage modulus (G′) after curing of at least 60 MPa at −30° C., 5 Hz, and 2% strain.

18. The process of claim 13 , wherein said first shell block polymer arms comprise one or more monomer residues derived from a conjugated diene, and the second shell block polymer arms comprise one or more monomer residues derived from an alkenyl substituted aromatic compound.

19. The process of claim 13 , wherein said polymerizing of steps (a), (b), and (c) is performed by living anionic polymerization.

Assignees

• Bridgestone Corp

Inventors

• Wang Xiaorong
• Kitano Hideki
• Pawlow James Herman
• Robertson Christopher G
• Chen Yaohong
• Yan Yuan-Yong

Classifications

• C08F297/046

  polymerising vinyl aromatic monomers and isoprene, optionally with other conjugated dienes · CPC title

• C08L2205/03

  containing three or more polymers in a blend · CPC title

• C08L9/06

  Copolymers with styrene · CPC title

• C08L2207/53

  Core-shell polymer · CPC title

• C08L21/00 Primary

  Compositions of unspecified rubbers · CPC title