Patent US413298A successfully refreshed from Google Patents.
Patent US4154920A successfully refreshed from Google Patents.
US4154920A
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US
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Methods for producing improved stable polyethylene terephthalate
Assignee: OI Glass Inc
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Filing: 1978-03-13
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Granted: 1979-05-15
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Expires: 1998-03-13
Abstract
Abstract Methods for producing improved, thermally-stable polyethylene terephthalate resins are provided. Polyethylene terephthalate resins are provided that can be fabricated into products such as carbonated beverage containers with a minimum of degradation products such as acetaldehyde preferably by rapidly polymerizing a prepolymer from an i.v. of about 0.2 to an i.v. of at least about 0.7.
Inventors
- 👤 Saleh A. Jabarin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 19:51
CPC Classifications
C; C08; C08G; C08G63/00; C08G63/78; C08G63/80; B; B01; B01J; B01J10/00; B01J10/02; B01J19/00; B01J19/18; B01J19/1862; B01J4/00; B01J4/001; B01J4/004; C08G63/02; C08G63/12; C08G63/16; C08G63/18; C08G63/181; C08G63/183; C08G63/785
Claims Analysis
Total Claims: 31
Claim 1
Independent Claim
100 words
A method of producing an improved, stable, polyethylene terephthalate resin from a low-molecular weight prepolymer of ethylene glycol and terephthalic acid having an intrinsic viscosity of about 0.1 to 0.3, the method comprising the steps of: (A) Further polymerizing the prepolymer to a higher intrinsic viscosity of about 0.4 to 0.6 at a temperature of about 270° C. to 290° C. at a high reaction rate for less than about one-half hour; and (B) Further polymerizing the reaction product of Step (A) in a solid state to provide a stable resin with an intrinsic viscosity of at least about 0.7.
Claim 2
Independent Claim
100 words
A method of producing an improved, stable, polyethylene terephthalate resin from a low-molecular weight prepolymer of ethylene glycol and terephthalic acid having an intrinsic viscosity of about 0.1 to 0.3, the method comprising the steps of: (A) Further polymerizing the prepolymer to a higher intrinsic viscosity of about 0.4 to 0.6 at a temperature of about 270° C. to 290° C. at a high reaction rate for less than about one-half hour; and (B) Further polymerizing the reaction product of Step (A) in a solid state to provide a stable resin with an intrinsic viscosity of at least about 0.7.
Claim 3
Dependent Claim
23 words
A method as defined in claim 1 including the additional steps forming an article from the stable polyethylene terephthalate resin of Step (B).
Claim 4
Dependent Claim
21 words
A method as defined in claim 1 and which the further polymerizing of Step (A) is done in a wiped-film reactor.
Claim 5
Dependent Claim
20 words
A stable polyethylene terephthalate resin made according to the method of claim 1 having an acetaldehyde content that is reduced.
Claim 6
Dependent Claim
27 words
A method as defined in claim 1 in which the further polymerizing in Step (B) is conducted in a temperature of about 200° C. to 240° C.
Claim 7
Dependent Claim
19 words
A method as defined in claim 1 in which the reaction time of Step (A) is about one-quarter hour.
Claim 8
Dependent Claim
55 words
A method as defined in claim 1 in which the further polymerizing of Step (A) includes forming a liquid film of the prepolymer and heating film to provide a further polymerizable prepolymer having a viscosity equivalent to that of about 200 to 400 poises at a temperature range of about 270° C. to 290° C.
Claim 9
Dependent Claim
20 words
A method as defined in claim 7 in which the film has a thickness of about one-half to 200 mils.
Claim 10
Dependent Claim
30 words
A method as defined in claim 7 in which the further polymerizable prepolymer has a viscosity equivalent to that of about 365 poises at 270° C. at zero shear rate.
Claim 11
Independent Claim
88 words
A method of providing an improved thermally stable polyethylene terephthalate prepolymer of ethylene glycol and terephthalic acid from a relatively low-molecular weight resin having an intrinsic viscosity of about 0.1 to 0.3, the method comprising the steps of: (A) Further polymerizing the prepolymer in a liquid state from a lower intrinsic viscosity to an intrinsic viscosity of at least 0.7 at a temperature of about 270° C. to 290° C. at a higher reaction rate for less than about one-half hour to provide a thermally-stable polyethylene terephthalate resin.
Claim 12
Independent Claim
88 words
A method of providing an improved thermally stable polyethylene terephthalate prepolymer of ethylene glycol and terephthalic acid from a relatively low-molecular weight resin having an intrinsic viscosity of about 0.1 to 0.3, the method comprising the steps of: (A) Further polymerizing the prepolymer in a liquid state from a lower intrinsic viscosity to an intrinsic viscosity of at least 0.7 at a temperature of about 270° C. to 290° C. at a higher reaction rate for less than about one-half hour to provide a thermally-stable polyethylene terephthalate resin.
Claim 13
Dependent Claim
16 words
A method as defined in claim 10 in which the reaction time is about one-quarter hour.
Claim 14
Dependent Claim
35 words
A method as defined in claim 10 employing the further step of further polymerizing the product of Step (A) in a solid state to provide a resin with an i.v. of at least about 0.8.
Claim 15
Dependent Claim
20 words
A method as defined in claim 10 including the additional step forming an article from the stable polyethylene terephthalate resin.
Claim 16
Dependent Claim
21 words
A method as defined in claim 10 in which the further polymerizing of Step (A) is accomplished in a wiped-film reactor.
Claim 17
Dependent Claim
20 words
A stable polyethylene terephthalate resin made according to the method of claim 10 having an acetaldehyde content that is reduced.
Claim 18
Dependent Claim
56 words
A method as defined in claim 10 in which the further polymerizing of Step (A) includes forming a liquid film of the prepolymer and heating the film to provide a stable polymer resin having a viscosity equal to about 3000 to 9000 poises at a range of 270° C. to 290° C. to zero shear rate.
Claim 19
Dependent Claim
20 words
A method as defined in claim 16 in which the film has a thickness of about one-half to 200 mils.
Claim 20
Dependent Claim
31 words
A method as defined in claim 16 in which the polymer of the film has a viscosity equivalent to that of about 3000 poises at 290° C. at zero shear rate.
Claim 21
Dependent Claim
40 words
A method as defined in claim 16 in which the film has a viscosity equivalent to that of about 1500 to 3000 poises at 290° C. at a shear rate of about 680 sec -1 to 6860 sec -1 .
Claim 22
Independent Claim
106 words
A method of producing an improved, stable,polyethylene terephthalate resin from a low-molecular weight prepolymer of ethylene glycol and terephthalic acid having an intrinsic viscosity of about 0.2, the method comprising the steps of (A) Further polymerizing the prepolymer at about 270° C. to 290° C. for a time greater than about one hour and less than about three hours to provide a product having an intrinsic viscosity of about 0.4 to 0.5, and (B) Further polymerizing the product of Step (A) in a solid state at about 200° C. to 240° C. to provide a stable resin having an intrinsic viscosity of at least about 0.7.
Claim 23
Independent Claim
106 words
A method of producing an improved, stable,polyethylene terephthalate resin from a low-molecular weight prepolymer of ethylene glycol and terephthalic acid having an intrinsic viscosity of about 0.2, the method comprising the steps of (A) Further polymerizing the prepolymer at about 270° C. to 290° C. for a time greater than about one hour and less than about three hours to provide a product having an intrinsic viscosity of about 0.4 to 0.5, and (B) Further polymerizing the product of Step (A) in a solid state at about 200° C. to 240° C. to provide a stable resin having an intrinsic viscosity of at least about 0.7.
Claim 24
Dependent Claim
21 words
A method as defined in claim 20 in which the further polymerizing of Step (A) is accomplished in about two hours.
Claim 25
Dependent Claim
22 words
A method as defined in claim 20 including the further step of forming the product of Step (B) into a solid article.
Claim 26
Dependent Claim
25 words
A method as defined in claim 2 in which there is included a further step of forming a bottle from the product of Step (B).
Claim 27
Dependent Claim
19 words
A method as defined in claim 2 in which the stable resin has an intrinsic viscosity of about 0.9.
Claim 28
Dependent Claim
18 words
A stable polyethylene resin made according to the method of claim 20 that has a reduced acetaldehyde content.
Claim 29
Dependent Claim
44 words
A method as defined in claim 20 in which the further polymerizable prepolymer product of Step (A) has, at a zero shear rate, a viscosity equivalent to that of about 200 to 400 poises at a temperature range of 270° C. to 290° C.
Claim 30
Dependent Claim
34 words
A method as defined in claim 20 in which the further polymerizable prepolymer product of Step (A) has a viscosity equivalent to that of about 365 poises at 270° C. at zero shear rate.
Claim 31
Dependent Claim
32 words
A method as defined in claim 20 in which the prepolymer product of Step (A) has a viscosity equivalent to that of about 1120 poises at 270° C. at zero shear rate.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-05-14 | 1982-11-13 | 1983-05-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-05-14 | 1986-11-13 | 1987-05-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-05-14 | 1990-11-13 | 1991-05-15 | $7700.00 | Window Closed / Lapsed |