US4536425A
Expired / Lapsed
US
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Method for preparing polar thermoplastic resin compositions having improved gas barrier properties
Assignee: PLASTIC PACKAGING PRODUCTS Co A CORP OF DELAWARE
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Filing: 1984-06-08
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Granted: 1985-08-20
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Expires: 2004-06-08
Abstract
Abstract A method of preparing a polar thermoplastic resin having improved resistance to gas permeability is disclosed wherein a blend of the resin and coarse mica flakes having an average particle size of less than about 100 mesh is prepared, the blend being prepared under mixing conditions which impart a shear force to the mica flakes sufficient to delaminate the flakes into individual platelets, substantially increasing the original aspect ratio of the flakes whereby an increase in the gas barrier properties of the resin is attained greater than that attained with fine mica flakes having an average particle size greater than about 100 mesh.
Inventors
- 👤 Ihab M. Hekal
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 13:48
CPC Classifications
C; C08; C08K; C08K3/00; C08K3/34; C08K2201/00; C08K2201/008; C08K2201/016; Y; Y10; Y10T; Y10T428/00; Y10T428/13; Y10T428/1352; Y10T428/1372; Y10T428/1379
Claims Analysis
Total Claims: 30
Claim 1
Independent Claim
91 words
A method of preparing a polar thermoplastic resin having increased resistance to gas permeability which comprises providing a blend of the resin and mica flakes having a plurality of platelets, the flakes having a particle size less than about 100 mesh before blending and then admixing the mica flakes and resin at a temperature at which the resin is molten, the admixing imparting a shear force which effects delamination of the mica platelets and a substantial increase in the aspect ratio whereby improved gas barrier and heat stability properties are achieved.
Claim 2
Independent Claim
91 words
A method of preparing a polar thermoplastic resin having increased resistance to gas permeability which comprises providing a blend of the resin and mica flakes having a plurality of platelets, the flakes having a particle size less than about 100 mesh before blending and then admixing the mica flakes and resin at a temperature at which the resin is molten, the admixing imparting a shear force which effects delamination of the mica platelets and a substantial increase in the aspect ratio whereby improved gas barrier and heat stability properties are achieved.
Claim 3
Dependent Claim
14 words
The method of claim 1 wherein the polar thermoplastic resin is a polyalkylene terephthalate.
Claim 4
Dependent Claim
12 words
The method of claim 2 wherein the polyalkylene terephthalate is polyethylene terephthalate.
Claim 5
Dependent Claim
26 words
The method of claim 1 wherein the average particle size of the mica flakes blended with the polyalkylene terephthalate is about 10 to about 100 mesh.
Claim 6
Dependent Claim
20 words
The method of claim 1 wherein the aspect ratio of the mica flakes before blending is less than about 40.
Claim 7
Dependent Claim
38 words
The method of claim 1 wherein the blend mixture is comprised of about 20 to about 80 percent by weight of the polar thermoplastic resin and about 20 to about 80 percent by weight of the mica flakes.
Claim 8
Dependent Claim
26 words
The method of claim 6 wherein a polyepoxide is added to the blend at a concentration of from about 0.1 to about 10 percent by weight.
Claim 9
Dependent Claim
16 words
The method of claim 7 wherein the polyepoxide is the condensate of Bisphenol A and epichlorohydrin.
Claim 10
Dependent Claim
21 words
The method of claim 1 wherein the admixing is performed at a temperature of about 200° C. to about 350° C.
Claim 11
Dependent Claim
19 words
The composition comprised of a blend of a polar polymer and mica prepared by the method of claim 1.
Claim 12
Dependent Claim
14 words
The composition of claim 10 wherein the polar thermoplastic resin is a polyalkylene terephthalate.
Claim 13
Dependent Claim
12 words
The composition of claim 11 wherein the polyalkylene terephthalate is polyethylene terephthalate.
Claim 14
Dependent Claim
38 words
The composition of claim 10 wherein the blend mixture is comprised of about 20 to about 80 percent by weight of the polar thermoplastic resin and about 20 to about 80 percent by weight of the mica flakes.
Claim 15
Dependent Claim
26 words
The composition of claim 13 wherein a polyepoxide is added to the blend at a concentration of from about 0.1 to about 10 percent by weight.
Claim 16
Dependent Claim
15 words
The composition of 14 wherein the polyepoxide is the condensate of Bisphenol A and epichlorohydrin.
Claim 17
Dependent Claim
15 words
The composition of 14 wherein the polyepoxide is the condensate of Bisphenol A and epichlorohydrin.
Claim 18
Independent Claim
122 words
A method of forming a thermoplastic container having increased gas barrier and heat stability properties and adapted to be used for the packaging of foodstuffs highly susceptible to oxidative deterioration which comprises providing a blend of a polar thermoplastic resin and mica flakes having a plurality of platelets, the flakes having an average particle size less than about 100 mesh, admixing the mica flakes and polar thermoplastic resin at a temperature at which the resin is molten, the admixing imparting a shear force which effects delamination of the mica platelets to effect a substantial increase in the aspect ratio of the flakes with a concommitant increase in the gas barrier properties of the resin, and then molding the admixture into a container.
Claim 19
Independent Claim
122 words
A method of forming a thermoplastic container having increased gas barrier and heat stability properties and adapted to be used for the packaging of foodstuffs highly susceptible to oxidative deterioration which comprises providing a blend of a polar thermoplastic resin and mica flakes having a plurality of platelets, the flakes having an average particle size less than about 100 mesh, admixing the mica flakes and polar thermoplastic resin at a temperature at which the resin is molten, the admixing imparting a shear force which effects delamination of the mica platelets to effect a substantial increase in the aspect ratio of the flakes with a concommitant increase in the gas barrier properties of the resin, and then molding the admixture into a container.
Claim 20
Dependent Claim
12 words
The method of claim 16 wherein the resin is a polyalkylene terephthalate.
Claim 21
Dependent Claim
13 words
The method of claim 17 wherein the polyalkylene terephthalate resin is polyethylene terephthalate.
Claim 22
Dependent Claim
27 words
The method of claim 16 wherein the aspect ratio of the mica flakes blended with the polyalkylene terephthalate has an aspect ratio of less than about 40.
Claim 23
Dependent Claim
51 words
The method of claim 16 wherein the blend mixture is comprised of about 20 to about 80 percent by weight of the polyalkylene terephthalate resin and about 15 to about 75 percent by weight of the mica flakes and about 0.5 to about 10 percent by weight of an epoxy resin.
Claim 24
Dependent Claim
25 words
The method of claim 16 wherein the mica flakes added to the blend have a particle size ranging from about 10 to about 60 mesh.
Claim 25
Dependent Claim
21 words
The method of claim 16 wherein the admixing is performed at a temperature of about 200° C. to about 300° C.
Claim 26
Dependent Claim
16 words
The method of claim 16 wherein the admixture is molded into a container by compression molding.
Claim 27
Dependent Claim
16 words
The method of claim 16 wherein the admixture is molded into a container by injection molding.
Claim 28
Dependent Claim
15 words
The method of claim 16 wherein the admixture is molded into a container by thermoforming.
Claim 29
Dependent Claim
9 words
A container manufactured by the method of claim 16.
Claim 30
Dependent Claim
9 words
A container manufactured by the method of claim 20.
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) | 1988-08-19 | 1989-02-18 | 1989-08-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-08-19 | 1993-02-18 | 1993-08-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-08-19 | 1997-02-18 | 1997-08-20 | $7700.00 | Window Closed / Lapsed |