US4100240A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Liquid polymer extrusion process and product
Assignee: Dow Silicones Corp
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Filing: 1976-09-30
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Granted: 1978-07-11
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Expires: 1996-09-30
Abstract
Abstract In accordance with a preferred embodiment of this invention there is provided a process for extruding an oriented-fiber reinforced tubular product. This product preferably is formed from a crosslinked polysiloxane elastomer produced by the curing of a fiber containing "liquid polymer" polysiloxane precursor. The subject process involves pumping the fiber containing precursor through a heated non-pumping extruder. The extruder initiates the curing reaction, shapes the reacting precursor into a tubular form and orients the fibers.
Inventors
- 👤 Giovanni Bassani
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 11:57
CPC Classifications
B; B29; B29C; B29C48/00; B29C48/25; B29C48/30; B29C48/32; B29C48/33; B29C48/022; B29C48/03; B29C48/09; B29K; B29K2101/00; B29K2101/10; B29K2105/00; B29K2105/06; B29K2105/12; B29K2301/00; B29K2301/10; B29K2709/00; B29K2709/08; Y; Y10; Y10T; Y10T428/00; Y10T428/13; Y10T428/1352; Y10T428/1372
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
195 words
A method of forming an oriented-fiber reinforced elastomeric tubular product by continuously extruding a liquid polymer precursor, said method employing a heated non-pumping extruder having rotatable forming surfaces to shape the precursor as it cures into said tubular product, said precursor being characterized by a room temperature Brookfield viscosity in the range of from 20 to 4000 centipoise and a cure time when heated to from about 150° to 250° C. of about 3 to about 1/2 seconds and wherein said non-pumping extruder the fibers are oriented to both provide increased strength to the tubular product and to facilitate said method by adding strength to the semi-cured extrudate as it emerges from said non-pumping extruder; said method comprising the steps of: (a) pumping said fiber containing liquid polymer precursor through said non-pumping extruder which is heated to initiate the curing reaction said precursor having a residence time in said extruder such that as the curing precursor emerges from the die it has reached a substantially self-sustaining state; and simultaneously (b) rotating at least one of the forming surfaces to orient said fibers; and (c) heating the semi-cured extrudate to drive the curing reaction toward completion.
Claim 2
Independent Claim
195 words
A method of forming an oriented-fiber reinforced elastomeric tubular product by continuously extruding a liquid polymer precursor, said method employing a heated non-pumping extruder having rotatable forming surfaces to shape the precursor as it cures into said tubular product, said precursor being characterized by a room temperature Brookfield viscosity in the range of from 20 to 4000 centipoise and a cure time when heated to from about 150° to 250° C. of about 3 to about 1/2 seconds and wherein said non-pumping extruder the fibers are oriented to both provide increased strength to the tubular product and to facilitate said method by adding strength to the semi-cured extrudate as it emerges from said non-pumping extruder; said method comprising the steps of: (a) pumping said fiber containing liquid polymer precursor through said non-pumping extruder which is heated to initiate the curing reaction said precursor having a residence time in said extruder such that as the curing precursor emerges from the die it has reached a substantially self-sustaining state; and simultaneously (b) rotating at least one of the forming surfaces to orient said fibers; and (c) heating the semi-cured extrudate to drive the curing reaction toward completion.
Claim 3
Independent Claim
196 words
A method of forming an oriented-fiber reinforced elastomeric polysiloxane tubular product by continuously extruding a liquid polymer polysiloxane precursor, said metod employing a heated non-pumping extruder having rotatable forming surfaces to form the precursor as it cures into said tubular product, said precursor being characterized by a room temperature visocity in the range of from 20 to 4000 centipoise and a cure time when heated to from about 150° to 250° C. of about 3 to about 1/2 seconds and wherein said non-pumping extruder the fibers are oriented to both provide increased strength to the tubular product and to facilitate said method by adding strength to the semi-cured extrudate as it emerges from said non-pumping extruder; said method comprising the steps of: (a) pumping said fiber containing liquid polymer precursor through said non-pumping extruder which is heated to initiate the curing reaction said precursor having a residence time in said extruder such that as the curing precursor emerges from the die it has reached a substantially self-sustaining state; and simulatenously (b) rotating at least one of the forming surfaces to orient said fibers; and (c) heating the semi-cured extrudate to drive the curing reaction toward completion.
Claim 4
Independent Claim
196 words
A method of forming an oriented-fiber reinforced elastomeric polysiloxane tubular product by continuously extruding a liquid polymer polysiloxane precursor, said metod employing a heated non-pumping extruder having rotatable forming surfaces to form the precursor as it cures into said tubular product, said precursor being characterized by a room temperature visocity in the range of from 20 to 4000 centipoise and a cure time when heated to from about 150° to 250° C. of about 3 to about 1/2 seconds and wherein said non-pumping extruder the fibers are oriented to both provide increased strength to the tubular product and to facilitate said method by adding strength to the semi-cured extrudate as it emerges from said non-pumping extruder; said method comprising the steps of: (a) pumping said fiber containing liquid polymer precursor through said non-pumping extruder which is heated to initiate the curing reaction said precursor having a residence time in said extruder such that as the curing precursor emerges from the die it has reached a substantially self-sustaining state; and simulatenously (b) rotating at least one of the forming surfaces to orient said fibers; and (c) heating the semi-cured extrudate to drive the curing reaction toward completion.
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 |