US3679774A
Expired / Lapsed
US
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Crystallized organopolysiloxane-polycarbonate block polymers and method for making them
Assignee: General Electric Co
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Filing: 1970-03-02
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Granted: 1972-07-25
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Expires: 1990-03-02
Abstract
Abstract Random alternating organopolysiloxane-polycarbonate block polymers can be crystallized by contacting the block polymer with a methylalkylketone in the vapor or liquid state. The resulting crystallized organopolysiloxane-polycarbonate block polymers exhibit improved physical characteristics, such as tensile strength (psi) and improved resistance to distortion at elevated temperature. The crystallized organopolysiloxane-polycarbonate block polymers can be employed as dielectrics and as permselective membranes for separating gases and vapors.
Inventors
- 👤 Donald G Le Grand
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 17:42
CPC Classifications
C; C08; C08G; C08G77/00; C08G77/42; C08G77/448; C08G64/00; C08G64/18; C08G64/186; C08L; C08L83/00; C08L83/10
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
39 words
Organopolysiloxane-polycarbonate block polymers in accordance with claim 1, having from 1 to 95 percent by weight of organopolysiloxane composed of blocks consisting essentially of chemically-combined diorganosiloxy units and from 5 to 99 percent by weight of blocks of polycarbonate.
Claim 2
Dependent Claim
25 words
A block polymer in accordance with claim 2, consisting essentially of chemically combined blocks of polydimethylsiloxane and the reaction product of carbonyl chloride and 2,2-bis(4-hydroxyphenyl)propane.
Claim 3
Independent Claim
175 words
A method which comprises effecting contact at a temperature in the range of from 0* to 250* C. of an organopolysiloxane-polycarbonate block polymer and a methylalkylketone selected from ketones having at least one methyl radical and an alkyl radical containing from two to eight carbon atoms, where said organopolysiloxane-polycarbonate block copolymer has the formula, where n is at least 1, a is equal to from about 15 to about 200, inclusive, b is equal to from about 5 to about 200, inclusive, while the ratio of a to b can vary from 0.05 to about 3, inclusive, u is an integer equal to from 1 to 4, inclusive, Y is A is a member selected from the class of hydrogen and R is a member selected from the class of hydrogen, monovalent hydrocarbon radicals and halogenated monovalent hydrocarbon radicals, R'' is a member selected from the class of monovalent hydrocarbon radicals, halogenated monovalent hydrocarbon radicals, and cyanoalkyl radicals, and Z is a member selected from the class of hydrogen, lower alkyl radicals and halogen radicals.
Claim 4
Dependent Claim
11 words
The method of claim 4, where the methylalkyl ketone is methylethylketone.
Claim 5
Dependent Claim
14 words
The method of claim 4, where the organopolysiloxane-polycarbonate block polymer is immersed in methylethylketone.
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) | 1975-07-25 | 1976-01-24 | 1976-07-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-07-25 | 1980-01-24 | 1980-07-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-07-25 | 1984-01-24 | 1984-07-25 | $7700.00 | Window Closed / Lapsed |