US4100122A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Trans-polyisoprene compositions
Assignee: Smith and Nephew Inc
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Filing: 1977-03-18
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Granted: 1978-07-11
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Expires: 1997-03-18
Abstract
Abstract Trans-polyisoprene composition of improved dimensional stability and stiffness are prepared by blending trans-polyisoprene with glass fibres and reinforcing silica. A crystalline wax may also be added to the compositions, to provide easier moldability.
Inventors
- 👤 Eric George Kent
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 20:42
CPC Classifications
A; A61; A61L; A61L15/00; A61L15/07; A61L15/12; A61F; A61F13/00; A61F13/04; A63; A63B; A63B37/00; A63B37/0003; A63B37/0023; A63B37/0024; A63B37/0026; A63B37/0029; A63B37/0037; C; C08; C08K; C08K7/00; C08K7/02; C08K7/04; C08K7/14
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
99 words
A thermoplastic remoldable composition of improved dimensional stability and stiffness comprising a mixture of 100 parts by weight of trans-1,4-poly-isoprene, 5 to 50 parts by weight of short, chopped glass fibres and 5 to 40 parts by weight of finely divided reinforcing silica filler, wherein said trans-1,4-polyisoprene is a high molecular weight polymer of isoprene having a trans-1,4 content of at least 85%, a crystallinity as determined by X-ray diffraction of about 15-40%, a Mooney viscosity (ML-4 at 100° C) of about 5 to 50 and a crystalline melting point of from about 20° C to about 80° C.
Claim 2
Dependent Claim
99 words
A thermoplastic remoldable composition of improved dimensional stability and stiffness comprising a mixture of 100 parts by weight of trans-1,4-poly-isoprene, 5 to 50 parts by weight of short, chopped glass fibres and 5 to 40 parts by weight of finely divided reinforcing silica filler, wherein said trans-1,4-polyisoprene is a high molecular weight polymer of isoprene having a trans-1,4 content of at least 85%, a crystallinity as determined by X-ray diffraction of about 15-40%, a Mooney viscosity (ML-4 at 100° C) of about 5 to 50 and a crystalline melting point of from about 20° C to about 80° C.
Claim 3
Dependent Claim
18 words
The composition of claim 1 wherein the silica filler has a particle size of 10 to 200 millimicrons.
Claim 4
Dependent Claim
26 words
The composition of claim 1 wherein the glass fibres have a length of 1/64 inch to 1/4 inch and a diameter of 2 to 50 microns.
Claim 5
Dependent Claim
28 words
The composition of claim 1 which also contains from 5 to 50 parts by weight of a crystalline wax having a melting point of at least 40° C.
Claim 6
Dependent Claim
19 words
The composition of claim 4 wherein the melting point of the crystalline wax is from 50° to 100° C.
Claim 7
Dependent Claim
19 words
The composition of claim 4 which also contains from 5 to 25 parts by weight of a hard clay.
Claim 8
Dependent Claim
29 words
The composition of claim 6 wherein the hard clay has a specific gravity of greater than 2.4 and at least 85% of particles of less than 2 micron size.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-07-10 | 1982-01-09 | 1982-07-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-07-10 | 1986-01-09 | 1986-07-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-07-10 | 1990-01-09 | 1990-07-11 | $7700.00 | Window Closed / Lapsed |