Deformation of polymeric materials
Abstract
Abstract A PROCESS FOR THE REDUCTION OF THE CROSS-SECTIONAL AREA OF AN ARTICLE OF THERMOPLASTIC POLYMERIC MATERIAL BY DRAWING IT THROUGH A WELL-LUBRICATED DIE, AT LEAST THAT PART OF THE ARTICLE TO WHICH THE DRAW-STRESS IS APPLIED BEING PRESTRENGTHENED BY MOLECULAR ORIENTATION. A PREFERRED FORM OF THE PROCESS INVOLVES APPLYING A SUBSTANTIAL DRAW-STRESS TO THE EXTRUDATE FROM A HYDROSTATIC EXTRUSION PROCESS. EXTRUDED AND/OR DRAWN ARTICLES OF THERMOPLASTIC POLYMERS MAY BE PRODUCED HAVING A HITHERTO, UNATTAINABLE DEGREE OF MOLECULAR ORIENTATION, AND, HENCE, PHYSICAL PROPERTIES, E.G., MODULUS. IT IS ALSO POSSIBLE TO OVERCOM THE EXCESSIBE ELAXATION OF THE PRODUCT HITHERTO ASSOCIATED WITH THE APPLICATION OF HYDROSTATIC EXRUSION TO SUCH MATERIALS.
Inventors
- 👤 J Bunney
- 👤 C Cassin
Bibliographic Details
Claims Analysis
Total Claims: 0References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-05-14 | 1976-11-13 | 1977-05-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-05-14 | 1980-11-13 | 1981-05-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-05-14 | 1984-11-13 | 1985-05-15 | $7700.00 | Window Closed / Lapsed |