US4770837A
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Method for making articles from polymer blends
Assignee: Mobil Oil AS
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Filing: 1986-11-03
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Granted: 1988-09-13
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Expires: 2006-11-03
Abstract
Abstract Polymer blends comprising a continuous matrix phase of thermoplastic polymer with a discontinuous phase of thermoplastic polymer distributed through it are produced by extruding a blend of immiscible thermoplastic polymers through an annular extrusion die which subjects the polymer blend to transverse shear forces prior to passing through the die lips. The application of the shear forces to the polymer blends produces improved uniformity of distribution of the continuous phase within the matrix, producing better properties in the finished article which may be a blown film or a blow molded product. The continuous matrix phase is suitably a polyolefin such as polyethylene and the discontinuous phase may be selected to provide the desired properties in the extruded article, for example, vapor barrier properties, strength, stiffness, and tear resistance. Typical polymers for the discontinuous phase are polyamides, EVA copolymers, polyacrylonitrile, polystyrene and various copolymers. The annular extrusion die which is used has an annular flow passage between two relatively moving walls in which the resin blend is subjected to the shear forces which promote the distribution of the continuous phase in the matrix.
Inventors
- 👤 Pang-Chia Lu
- 👤 Gordon V. Sharps
- 👤 Tien-Kuei Su
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 03:55
CPC Classifications
B; B29; B29C; B29C48/00; B29C48/25; B29C48/36; B29C48/362; B29C48/022; B29C48/03; B29C48/09; B29C48/10; B29C48/14; B29C48/147; B29C48/1472; B29C48/16; B29C48/18; B29C48/21; B29C48/30; B29C48/32; B29C48/33; B29C48/335; B29C48/337; B29C2791/00; B29C2791/004; B29C2791/007; B29C48/001; B29C48/0018; B29C48/0019; B29C48/05; B29C48/07; B29C48/08; B29K; B29K2023/00; B29K2023/04; B29K2023/06; B29K2023/08; B29K2023/083; B29K2995/00; B29K2995/0037; B29K2995/0063
Claims Analysis
Total Claims: 26
Claim 1
Independent Claim
136 words
In a method of making an extrudate of a ternary heterogenous polymer blend comprising a continuous thermoplastic resin matrix having a discontinuous phase of a thermoplastic resin distributed within the matrix wherein the blend contains a compatibilizer resin to improve interfacial adherence between the resin of the continuous matrix phase and the resin of the discontinuous phase, the improvement which comprises subjecting the polymer blend to shear forces transverse to the direction of polymer movement in the extrusion die prior to passing through the die lips, said die having an annular flow passage which extends axially of the die between an outer die wall and an inner die wall wherein one of the inner and outer die walls is rotated relative to one another, and thereby obtaining an extruded polymer blend having improved vapor barrier properties.
Claim 2
Dependent Claim
136 words
In a method of making an extrudate of a ternary heterogenous polymer blend comprising a continuous thermoplastic resin matrix having a discontinuous phase of a thermoplastic resin distributed within the matrix wherein the blend contains a compatibilizer resin to improve interfacial adherence between the resin of the continuous matrix phase and the resin of the discontinuous phase, the improvement which comprises subjecting the polymer blend to shear forces transverse to the direction of polymer movement in the extrusion die prior to passing through the die lips, said die having an annular flow passage which extends axially of the die between an outer die wall and an inner die wall wherein one of the inner and outer die walls is rotated relative to one another, and thereby obtaining an extruded polymer blend having improved vapor barrier properties.
Claim 3
Dependent Claim
25 words
A method according to claim 1 in which the polymer forming the discontinuous phase constitutes less than 50 weight percent of the total resin composition.
Claim 4
Dependent Claim
25 words
A method according to claim 2 in which the polymer forming the discontinuous phase constitutes 10 to 30 weight percent of the total resin composition.
Claim 5
Dependent Claim
31 words
A method according to claim 1 in which the discontinuous phase of the extrudate is present in the form of thin, overlapping substantially parallel layers embedded in the continuous matrix phase.
Claim 6
Dependent Claim
16 words
A method according to claim 1 in which the continuous matrix phase polymer comprises a polyolefin.
Claim 7
Dependent Claim
19 words
A method according to claim 1 in which the discontinuous phase resin comprises a resin having vapor barrier properties.
Claim 8
Dependent Claim
27 words
A method according to claim 6 in which the polymer having vapor barrier properties comprises a polyamide or an ethylene/vinyl acetate copolymer or an ethylene/vinyl alcohol copolymer.
Claim 9
Dependent Claim
20 words
A method according to claim 1 in which the extrudate from the die is expanded to form a blown film.
Claim 10
Dependent Claim
32 words
A method according to claim 8 in which the polymer blend is fed into the annular flow passage through at least one ring of holes arranged concentrically with the annular flow passage.
Claim 11
Dependent Claim
47 words
A method according to claim 9 in which the tubular extrusion die includes a plurality of concentrically arranged rings of holes for injecting polymer into the annular flow passage, each ring being arranged between the inner and outer wall and connected with an inlet for molten polymer.
Claim 12
Dependent Claim
33 words
A method according to claim 10 in which the die has three concentric rings of holes and the polymer blend is passed into the annular flow passage through the middle ring of holes.
Claim 13
Dependent Claim
27 words
A method according to claim 11 in which a thermoplastic polymer is passed into the annular flow passage through the inner and outer rings of concentric holes.
Claim 14
Dependent Claim
24 words
A method according to claim 12 in which the thermoplastic polymer passed into the inner and outer concentric rings of holes comprises a polyolefin.
Claim 15
Dependent Claim
184 words
In a method of making a thermoplastic resin film by blown film extrusion of a ternary heterogenous polymer blend comprising a compatibilizer resin, a continuous thermoplastic resin matrix and a discontinuous phase of a thermoplastic resin distributed within the matrix in which a molten stream of thermoplastic resin is extruded through an annular extrusion die to form a tubular extrudate which is expanded by means of internal gas pressure and longitudinally stretched to provide orientation in the film, the improvement which comprises extruding a thermoplastic polymer as the discontinuous phase of the blend through an annular extrusion die having an annular flow passage in which the resin mixture to be extruded is subjected to shear forces transverse to the direction of polymer movement in the extrusion die prior to passing through the die lips, said die having an annular flow passage which extends axially of the die between an outer die wall and an inner die wall wherein one of the inner and outer die walls is rotated relative to one another, and thereby obtaining an extruded polymer blend having improved vapor barrier properties.
Claim 16
Dependent Claim
184 words
In a method of making a thermoplastic resin film by blown film extrusion of a ternary heterogenous polymer blend comprising a compatibilizer resin, a continuous thermoplastic resin matrix and a discontinuous phase of a thermoplastic resin distributed within the matrix in which a molten stream of thermoplastic resin is extruded through an annular extrusion die to form a tubular extrudate which is expanded by means of internal gas pressure and longitudinally stretched to provide orientation in the film, the improvement which comprises extruding a thermoplastic polymer as the discontinuous phase of the blend through an annular extrusion die having an annular flow passage in which the resin mixture to be extruded is subjected to shear forces transverse to the direction of polymer movement in the extrusion die prior to passing through the die lips, said die having an annular flow passage which extends axially of the die between an outer die wall and an inner die wall wherein one of the inner and outer die walls is rotated relative to one another, and thereby obtaining an extruded polymer blend having improved vapor barrier properties.
Claim 17
Dependent Claim
22 words
A method according to claim 14 in which the discontinuous phase comprises less than 50 weight percent of the total resin composition.
Claim 18
Dependent Claim
14 words
A method according to claim 14 in which the continuous phase comprises a polyolefin.
Claim 19
Dependent Claim
16 words
A method according to claim 16 in which the continuous phase comprises linear, low density polyethylene.
Claim 20
Dependent Claim
25 words
A method according to claim 14 in which the discontinuous phase comprises a resin having vapor barrier properties greater than that of the continuous phase.
Claim 21
Dependent Claim
160 words
In a method of making a layered thermoplastic resin film by blown film extrusion of a ternary heterogenuous polymer blend comprising a compatibilizer resin, a continuous thermoplastic resin matrix and a discontinuous phase of a thermoplastic resin distributed within the matrix in which a plurality of streams of molten thermoplastic resin are co-extruded through an annular extrusion die to form a tubular extrudate which is expanded by means of internal gas pressure and longitudinally stretched to provide orientation in the film, the improvement which comprises subjecting the polymer blend to shear forces transverse to the direction of polymer movement in the extusion die prior to passing through the die lips, said die having an annular flow passage which extends axially of the die between an outer die wall and an inner die wall wherein one of the inner and outer die walls is rotated relative to one another, and thereby obtaining an extruded polymer blend having improved vapor barrier properties.
Claim 22
Dependent Claim
160 words
In a method of making a layered thermoplastic resin film by blown film extrusion of a ternary heterogenuous polymer blend comprising a compatibilizer resin, a continuous thermoplastic resin matrix and a discontinuous phase of a thermoplastic resin distributed within the matrix in which a plurality of streams of molten thermoplastic resin are co-extruded through an annular extrusion die to form a tubular extrudate which is expanded by means of internal gas pressure and longitudinally stretched to provide orientation in the film, the improvement which comprises subjecting the polymer blend to shear forces transverse to the direction of polymer movement in the extusion die prior to passing through the die lips, said die having an annular flow passage which extends axially of the die between an outer die wall and an inner die wall wherein one of the inner and outer die walls is rotated relative to one another, and thereby obtaining an extruded polymer blend having improved vapor barrier properties.
Claim 23
Dependent Claim
20 words
A method according to claim 19 in which the heterogeneuous blend comprises the central layer of a three layer film.
Claim 24
Dependent Claim
36 words
A method acording to claim 20 in which the heterogeneous blend comprises a blend of a polyolefin matrix and a discontinuous phase of a polymer having better vapor barrier properties or greater strength than the polyolefin.
Claim 25
Dependent Claim
18 words
A method according to claim 21 in which the discontinuous phase comprises a polyamide or an EVA copolymer.
Claim 26
Dependent Claim
12 words
A method according to claim 21 in which the polyolefin is LLDPE.
References Cited (Backward Citations)
US2973783A
Cited
US3093255A
Cited
US3632711A
Cited
US3966861A
Cited
US3759647A
Cited
US3716612A
Cited
US3933960A
Cited
US3857754A
Cited
US3962396A
Cited
US4109037A
Cited
US4420451A
Cited
US4217161A
Cited
US4233367A
Cited
JPS5388060A
Cited
JPS53108162A
Cited
US4410482A
Cited
US4247584A
Cited
US4532100A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-09-13 | 1992-03-14 | 1992-09-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-09-13 | 1996-03-14 | 1996-09-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-09-13 | 2000-03-14 | 2000-09-13 | $7700.00 | Window Closed / Lapsed |