US3886683A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Degradable plastic
Assignee: Princeton Chemical Research Inc
•
Filing: 1970-11-27
•
Granted: 1975-06-03
•
Expires: 1990-11-27
Abstract
Abstract Films and containers are made from polymers of butene-1 such as polybutene-1 which contains a small amount of stabilizer whereby the rapid degradation rate of polybutene-1 can be controlled so that it will degrade after predetermined exposure to sunlight. This renders such products especially suited for agricultural mulch films, where they need not be removed after a growing season, and for throw-away containers where they will decompose in garbage dumps or if discarded as litter. The thermal history of the polymer will also affect its degradation rate. The rate is measured in terms of thermally adjusted Langley units (TALU) since it has been found that the ambient temperature affects decomposition as well as the Langley units of solar radiation exposure.
Inventors
- 👤 Donald E Hudgin
- 👤 Murray Reich
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 19:01
CPC Classifications
A; A01; A01G; A01G13/00; A01G13/30; A01G13/32; A01G13/33; C; C08; C08K; C08K5/00; C08K5/0008; C08K5/0033; Y; Y10; Y10S; Y10S260/00; Y10S260/43
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
198 words
IN THE GROWING OF AN AGRICULTURAL CROP IN A FIELD IN WHICH THE FIELD IS AT LEAST PARTIALLY COVERED WITH A PLASTIC FILM FOR A PREDETERMINED GROWTH PERIOD, THE IMPROVEMENT WHICH COMPRISES ASCERTAINING, FROM THE METERIOLOGICAL DATA FOR THE GEOGRAPHIC AREA IN WHICH SAID FIELD IS LOCATED, THE AMOUNT OF TALU FOR SAID PREDETERMINED GROWTH PERIOD, AND COVERING SAID FIELD WITH A FILM HAVING A THICKNESS UP TO ABOUT 100 MILS AND COMPRISING A POLYMER COMPRISING AT LEAST ABOUT 75% BY WEIGHT OF UNITS OF BUTENE-1, BEING OVER 50% ISOTACTIC AND HAVING A MOLECULAR WEIGHT IN EXCESS OF ABOUT 40,000, AND ABOUT 0.01 TO 5% BY WEIGHT OF A STABILIZER, THE THERMAL TREATMENT OF SAID POLYMER PRIOR THE TIME WHEN IT IS APPLIED TO SAID FIELD AS A FILM HAVING BEEN SUCH AS TO REDUCE ITS INITIAL STABILITY BY AT LEAST ABOUT 5,000 TALU, SAID FILM HAVING A STABILITY APPROXIMATELY THAT OF THE TALU DETERMINED BUT AT LEAST ABOUT 5,000 BUT NOT IN EXCESS OF ABOUT 70,000 TALU, WHEREBY THE FILM WILL DEGRADE AFTER SAID PREDETERMINED GROWTH PERIOD, THE DEGRADATION BEING ACCELERATED OR DECELERATED IN ACCORDANCE WITH AN ACCELERATION OR DECELERATION OF CROP GROWTH DUE TO CLIMATIC CONDITIONS.
Claim 2
Dependent Claim
198 words
IN THE GROWING OF AN AGRICULTURAL CROP IN A FIELD IN WHICH THE FIELD IS AT LEAST PARTIALLY COVERED WITH A PLASTIC FILM FOR A PREDETERMINED GROWTH PERIOD, THE IMPROVEMENT WHICH COMPRISES ASCERTAINING, FROM THE METERIOLOGICAL DATA FOR THE GEOGRAPHIC AREA IN WHICH SAID FIELD IS LOCATED, THE AMOUNT OF TALU FOR SAID PREDETERMINED GROWTH PERIOD, AND COVERING SAID FIELD WITH A FILM HAVING A THICKNESS UP TO ABOUT 100 MILS AND COMPRISING A POLYMER COMPRISING AT LEAST ABOUT 75% BY WEIGHT OF UNITS OF BUTENE-1, BEING OVER 50% ISOTACTIC AND HAVING A MOLECULAR WEIGHT IN EXCESS OF ABOUT 40,000, AND ABOUT 0.01 TO 5% BY WEIGHT OF A STABILIZER, THE THERMAL TREATMENT OF SAID POLYMER PRIOR THE TIME WHEN IT IS APPLIED TO SAID FIELD AS A FILM HAVING BEEN SUCH AS TO REDUCE ITS INITIAL STABILITY BY AT LEAST ABOUT 5,000 TALU, SAID FILM HAVING A STABILITY APPROXIMATELY THAT OF THE TALU DETERMINED BUT AT LEAST ABOUT 5,000 BUT NOT IN EXCESS OF ABOUT 70,000 TALU, WHEREBY THE FILM WILL DEGRADE AFTER SAID PREDETERMINED GROWTH PERIOD, THE DEGRADATION BEING ACCELERATED OR DECELERATED IN ACCORDANCE WITH AN ACCELERATION OR DECELERATION OF CROP GROWTH DUE TO CLIMATIC CONDITIONS.
Claim 3
Dependent Claim
199 words
In the growing of an agricultural crop in a field in which the field is at least partially covered with a plastic film for a predetermined growth period, the improvement which comprises ascertaining, from the meteorological data for the geographic area in which said field is located, the amount of TALU for said predetermined growth period, and covering said field with a film having a thickness up to about 100 mils and comprising a polymer comprising at least about 75% by weight of units of butene-1, being over 50% isotactic and having a molecular weight in excess of about 40,000, and about 0.01 to 5% by weight of a stabilizer, the thermal treatment of said polymer prior to the time when it is applied to said field as a film having been such as to reduce its initial stability by at least about 5,000 TALU, said film having a stability approximately that of the TALU determined but at least about 5,000 but not in excess of about 70,000 TALU, whereby the film will degrade after said predetermined growth period, the degradation being accelerated or decelerated in accordance with an acceleration or deceleration of crop growth due to climactic conditions.
Claim 4
Dependent Claim
199 words
In the growing of an agricultural crop in a field in which the field is at least partially covered with a plastic film for a predetermined growth period, the improvement which comprises ascertaining, from the meteorological data for the geographic area in which said field is located, the amount of TALU for said predetermined growth period, and covering said field with a film having a thickness up to about 100 mils and comprising a polymer comprising at least about 75% by weight of units of butene-1, being over 50% isotactic and having a molecular weight in excess of about 40,000, and about 0.01 to 5% by weight of a stabilizer, the thermal treatment of said polymer prior to the time when it is applied to said field as a film having been such as to reduce its initial stability by at least about 5,000 TALU, said film having a stability approximately that of the TALU determined but at least about 5,000 but not in excess of about 70,000 TALU, whereby the film will degrade after said predetermined growth period, the degradation being accelerated or decelerated in accordance with an acceleration or deceleration of crop growth due to climactic conditions.
Claim 5
Dependent Claim
17 words
The process of claim 1 wherein the film has a stability of at least about 10,000 TALU.
References Cited (Backward Citations)
US2675366A
Cited
US3265648A
Cited
US3218276A
Cited
US3266918A
Cited
US3280220A
Cited
US3356666A
Cited
US3274731A
Cited
US3320695A
Cited
US3341357A
Cited
US3502613A
Cited
US3454510A
Cited
US3454523A
Cited
US3440212A
Cited
US3536661A
Cited
US3580898A
Cited
US3549588A
Cited
US3538092A
Cited
US3679777A
Cited
US3590528A
Cited
US3673134A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-06-02 | 1978-12-02 | 1979-06-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-06-02 | 1982-12-02 | 1983-06-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-06-02 | 1986-12-02 | 1987-06-03 | $7700.00 | Window Closed / Lapsed |