Process and catalysts for hydrogen mediated anionic copolymerization of conjugated dienes and liquid copolymers thereof
AssigneeAlbemarle Corporation
InventorWilliam J. Layman
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Abstract
The disclosure relates to hydrogen mediated anionically copolymerized conjugated diene vinyl aromatic compositions, copolymers of isoprene and/or butadiene with styrene, and processes and compositions for preparing them.
Claims38
A process for copolymerizing conjugated dienes with vinylaromatic comonomers in a hydrocarbon reaction medium, comprising
- a) chemically adding a lithium alkoxide complexed saline hydride (LOXSH) catalyst to a low boiling conjugated diene to form a polymerization initiating species,
- b) contemporaneously co-feeding the vinylaromatic comonomer with at least two gaseous and/or volatile compounds to the reaction medium, wherein the at least two gaseous and/or volatile compounds comprise hydrogen and the low boiling conjugated diene, and
- c) polymerizing at least a portion of the conjugated diene,
- wherein the LOXSH reagent comprises one or more σ−μ polar modifiers.
A process for hydrogen mediated copolymerization of conjugated dienes with vinylaromatic monomers in a hydrocarbon reaction medium, comprising chemically adding lithium alkoxide complexed saline hydride (LOXSH) catalyst to a low boiling conjugated diene and/or to a vinylaromatic comonomer to form a polymerization initiating species, and co-feeding at least two gaseous and/or volatile compounds to the reaction medium, wherein the at least two gaseous and/or volatile compounds comprise hydrogen and the low boiling conjugated diene, wherein the LOXSH catalyst comprises one or more σ−μ polar modifiers.
An LOXSH catalyst or reagent composition, wherein the composition is selective for 1,4-CD monomer microstructure enchainment in a VA-CD copolymer composition, and the LOXSH composition comprises 1) at least one tertiary amino alcohol σ−μ polar modifiers having a 2° or a 3° alcohol functional group;
- 2) an organolithium compound;
- and 3) optionally elemental hydrogen and/or an organo silicon hydride.
An LOXSH catalyst or reagent composition, wherein the composition is selective for 3,4-CD and/or 1,2-CD-vinyl monomer microstructure enchainment, and the composition comprises:
- a) at least one tertiary amino alcohol σ−μ or amino-ether-alcohol polar modifiers;
- b) optionally at least one separate ether-alcohol σ−μ polar modifiers;
- c) an organo lithium compound;
- and d) optionally elemental hydrogen and/or an organo silicon hydride.
A hydrogen mediated anionic VA-CD copolymer composition that is characterized as having:
- 1) number average degree of polymerization (DPn) in the range of about 7 to about 50 repeating units;
- 2) a Brookfield viscosity (45° C.) in the range of about 10 cP to about 300,000 cP;
- 3) 1,4-CD microstructure content in the range of 20% to about 80% based on the conjugated diene portion;
- and 4) glass transition temperature Tg in the range of about −110° C. to about 5° C.
Dependencies are inferred from the claim text.