EP0024810A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Production of shaped articles by removal of solvent from gels of high molecular weight crystalline polymers
Assignee: Syngenta Ltd
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Filing: 1980-07-23
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Granted: —
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Expires: 2000-07-23
Abstract
Abstract A process of forming shaped articles comprising forming a free draining gel from a solution of a crystallisable, high molecular weight polymer under conditions which cause crystallisation of the polymer and subjecting the gel to a non-random deformation process so that the associated solvent is expressed. Some residual solvent may be present and can assist in subsequent fabrication processes but the solvent may also be completely removed for such processes. The resulting products have good physical properties, particularly in modulus after uniaxial or biaxial drawing.
Inventors
- 👤 Peter John Barham
- 👤 Alan Selwood
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-26 13:52
CPC Classifications
D; D01; D01F; D01F6/00; D01F6/58; D01F6/62; D01F6/625; B; B29; B29C; B29C55/00; B29C55/005; C; C08; C08F; C08F6/00; C08F6/06; C08F6/12; C08G; C08G63/00; C08G63/02; C08G63/06; C08G63/88; C08J; C08J3/00; C08J3/02; C08J3/09; C08J3/11; C08J5/00; C08J5/18; C12; C12P; C12P7/00; C12P7/62; C12P7/625; D01D; D01D5/00; B29K; B29K2023/00; B29K2023/04; B29K2023/06; B29K2105/00; B29K2105/0058; B29K2105/0061; B29K2995/00; B29K2995/0037; B29K2995/0088
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
35 words
A process comprising forming a free draining gel from a solution of a crystallisable high molecular weight polymer under conditions which cause crystallisation of the polymer and subjecting the gel to a non-random deformation process.
Claim 2
Dependent Claim
35 words
A process comprising forming a free draining gel from a solution of a crystallisable high molecular weight polymer under conditions which cause crystallisation of the polymer and subjecting the gel to a non-random deformation process.
Claim 3
Dependent Claim
28 words
A process according to Claim 1 in which the gel is formed by cooling a solution of the polymer to a temperature at which the solution is supersaturated.
Claim 4
Dependent Claim
18 words
A process according to Claim 2 in which the solution is agitated at least during the cooling step.
Claim 5
Dependent Claim
45 words
. A process according to Claim 2 in which the solution is not agitated during the cooling step and is quenched through the temperature at which crystallisation is at its maximum rate to a temperature at least below that at which fibrous crystals can grow.
Claim 6
Dependent Claim
23 words
A process according to any one of the preceding claims in which a miscible non-solvent is added to the solution of the polymer.
Claim 7
Dependent Claim
22 words
A process according to any of the preceding claims in which the non-random deformation process comprises pressing the gel between opposed surfaces.
Claim 8
Dependent Claim
21 words
A process according to any one of Claims 1 to 5 in which the non-random deformation process comprises stretching the gel.
Claim 9
Dependent Claim
36 words
A process according to any one of Claims 1 to 7 in which the non-random deformation process is applied to remove only part of the solvent and the product thereof is fabricated into a shaped article.
Claim 10
Dependent Claim
27 words
A process according to any one of the preceding claims in which the product obtained by subjecting the gel to the non-random deformation process is then oriented.
Claim 11
Dependent Claim
16 words
A process according to any one of the preceding claims in which the polymer is poly(hydroxybutyrate).
Claim 12
Dependent Claim
21 words
Poly(hydroxybutyrate) exhibiting a first melting point as measured by Differential Thermal Analysis at a heating rate of 10°C/min of approximately 150°C.
Claim 13
Dependent Claim
21 words
Poly(hydroxybutyrate) exhibiting a first melting point as measured by Differential Thermal Analysis at a heating rate of 10°C/min of approximately 150°C.
Claim 14
Dependent Claim
22 words
Shaped articles which have been formed by subjecting a gel of a crystallisable, high molecular weight polymer to a non-random deformation process.
Claim 15
Dependent Claim
22 words
Shaped articles which have been formed by subjecting a gel of a crystallisable, high molecular weight polymer to a non-random deformation process.
References Cited (Backward Citations)
No citation records indexed.
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