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US4108945A Expired / Lapsed US ⏱️ 0.0 years remaining

Star polymers and process for the preparation thereof

Assignee: University of Akron
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Filing: 1976-03-03
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Granted: 1978-08-22
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Expires: 1996-03-03
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Abstract

Abstract Disclosed is a series of star polymer products having at least three polymeric arms which radiate from a nucleus having at least two molecules of a linking compound. The polymeric arms may be copolymers of conjugated dienes and monovinyl aromatic compounds and/or homopolymers of either monomer. A novel process for the preparation of the polymer products includes the steps of forming the polymeric arms with an organometallic initiator to form polymers terminated by an active chain end and thereafter forming a nucleus with the simultaneous linking of the active chain ends thereto. The nucleus is formed from at least two molecules of a linking compound each having at least two functional groups.

Inventors

  • 👤 Lewis J. Fetters
  • 👤 Le-Khac Bi

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 16:37
CPC Classifications
C; C08; C08G; C08G81/00; C08G81/02; C08G81/021; C08G81/022; C08C; C08C19/00; C08C19/30; C08C19/42; C08C19/44

Claims Analysis

Total Claims: 9
Claim 1
Independent Claim 112 words
A star polymer product comprising: a nucleus having a plurality of molecules of a linking compound selected from the group consisting of aliphatic and aromatic diisocyanates, and aliphatic and aromatic diepoxides, diketones and dialdehydes having up to about 12 carbon atoms; at least ten polymeric arms linked to said nucleus wherein said polymeric arms are formed from conjugated dienes and the ratio of molecules of linking compound to the number of polymeric arms in said star polymer is at least 6:1; and characterized in that: the number average molecular weight of said star polymer product is at least 500,000 and the intrinsic viscosity thereof ranges from about 0.1 to about 2.0 dl/gm.
Claim 2
Dependent Claim 112 words
A star polymer product comprising: a nucleus having a plurality of molecules of a linking compound selected from the group consisting of aliphatic and aromatic diisocyanates, and aliphatic and aromatic diepoxides, diketones and dialdehydes having up to about 12 carbon atoms; at least ten polymeric arms linked to said nucleus wherein said polymeric arms are formed from conjugated dienes and the ratio of molecules of linking compound to the number of polymeric arms in said star polymer is at least 6:1; and characterized in that: the number average molecular weight of said star polymer product is at least 500,000 and the intrinsic viscosity thereof ranges from about 0.1 to about 2.0 dl/gm.
Claim 3
Dependent Claim 41 words
A star polymer product, as set forth in claim 1, further characterized in that: the tensile strengths of said star polymers are higher than those exhibited for linear products formed from said block copolymers of comparable molecular weight and percentage composition.
Claim 4
Dependent Claim 123 words
A star polymer product comprising: a nucleus having a plurality of molecules of a linking compound selected from the group consisting of aliphatic and aromatic diisocyanates, and aliphatic and aromatic diepoxides, diketones and dialdehydes having up to about 12 carbon atoms; at least ten polymeric arms linked to said nucleus wherein said polymeric arms are selected from the group consisting of block copolymers of conjugated diene and monovinyl aromatic homopolymers and the ratio of molecules of linking compound to the number of polymeric arms in said star polymer is at least 6:1; and characterized in that: the number average molecular weight of said star polymer product is at least 500,000 and the intrinsic viscosity thereof ranges from about 0.5 to about 1.4 dl/gm.
Claim 5
Dependent Claim 123 words
A star polymer product comprising: a nucleus having a plurality of molecules of a linking compound selected from the group consisting of aliphatic and aromatic diisocyanates, and aliphatic and aromatic diepoxides, diketones and dialdehydes having up to about 12 carbon atoms; at least ten polymeric arms linked to said nucleus wherein said polymeric arms are selected from the group consisting of block copolymers of conjugated diene and monovinyl aromatic homopolymers and the ratio of molecules of linking compound to the number of polymeric arms in said star polymer is at least 6:1; and characterized in that: the number average molecular weight of said star polymer product is at least 500,000 and the intrinsic viscosity thereof ranges from about 0.5 to about 1.4 dl/gm.
Claim 6
Dependent Claim 17 words
A star polymer product, as set forth in claim 3, wherein said linking compound is 1,6-hexamethylene diisocyanate.
Claim 7
Dependent Claim 17 words
A star polymer product, as set forth in claim 3, wherein said linking compound is diphenylmethane diisocyanate.
Claim 8
Dependent Claim 39 words
A star polymer product, as set forth in claim 3, wherein said conjugated diene has a molecular weight ranging from 5,000 to about 200,000 and said monovinyl aromatic compound has a molecular weight ranging from 5,000 to about 100,000.
Claim 9
Dependent Claim 48 words
A star polymer product, as set forth in claim 3, wherein said conjugated diene is selected from the group consisting of butadiene and isoprene and said monovinyl aromatic compound is selected from the group consisting of sytrene and alkylated styrenes having from 8 to about 20 carbon atoms.

References Cited (Backward Citations)

US3281383A Cited
GB1025295A Cited
DE1245132B Cited
US3637554A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1981-08-21 1982-02-20 1982-08-22 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1985-08-21 1986-02-20 1986-08-22 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1989-08-21 1990-02-20 1990-08-22 $7700.00 Window Closed / Lapsed

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