US4167544A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Polymer blends
Assignee: Massachusetts Institute of Technology
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Filing: 1978-08-23
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Granted: 1979-09-11
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Expires: 1998-08-23
Abstract
Abstract Homogeneous blends are provided comprising a diblock copolymer of isoprene and butadiene and a homopolymer constituent which is polyisoprene, polybutadiene or mixtures of polyisoprene and polybutadiene.
Inventors
- 👤 Alonso R. Ramos
- 👤 Robert E. Cohen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 07:53
CPC Classifications
C; C08; C08L; C08L9/00; Y; Y10; Y10S; Y10S260/00; Y10S260/30; Y10S260/32
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
60 words
A homogeneous composition comprising a diblock copolymer of isoprene and butadiene, and a homopolymer constituent selected from the group consisting of polyisoprene, polybutadiene and mixtures thereof wherein the average molecular weight of the homopolymer constituent is within the range of about 50 to 1000% of the average molecular weight of the corresponding polyisoprene or polybutadiene chain of the diblock copolymer.
Claim 2
Dependent Claim
60 words
A homogeneous composition comprising a diblock copolymer of isoprene and butadiene, and a homopolymer constituent selected from the group consisting of polyisoprene, polybutadiene and mixtures thereof wherein the average molecular weight of the homopolymer constituent is within the range of about 50 to 1000% of the average molecular weight of the corresponding polyisoprene or polybutadiene chain of the diblock copolymer.
Claim 3
Dependent Claim
18 words
The composition of claim 1 comprising a diblock copolymer of isoprene and butadiene and a homopolymer of isoprene.
Claim 4
Dependent Claim
18 words
The composition of claim 1 comprising a diblock copolymer of isoprene and butadiene and a homopolymer of butadiene.
Claim 5
Dependent Claim
26 words
The composition of claim 1 wherein the homopolymer constituent comprises polyisoprene and ploybutadiene and said copolymer comprises at least about 50 weight percent of said composition.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-09-10 | 1983-03-12 | 1983-09-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-09-10 | 1987-03-12 | 1987-09-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-09-10 | 1991-03-12 | 1991-09-11 | $7700.00 | Window Closed / Lapsed |