EP0144983A2
Expired / Lapsed
EP
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Process for preparing polyacrylonitrile articles having high tensile strength and modulus
Assignee: DSM BV
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Filing: 1984-12-06
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Granted: —
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Expires: 2004-12-06
Abstract
Abstract Polyacrylonitrile articles, such as filaments, tapes and films, having high tensile strength and modulus, and prepared by adding to a solution of polyacrilontrile with a molecular weight above 3 x 10 5 , pref. above 5 x 10 5 , a minor amount of a bivalent metal compound, converting the solution into a solvent containing article, cooling this article to form a gelarticle, removing from this gel the solvent and metal compound, and stretching the resulting article at increased temperature. With this process filaments with a tensile strength above 1.2 GPa and a modulus above 16 GPa can be obtained.
Inventors
- 👤 Ronald Michael Alexander Maria Schellekens
- 👤 Pieter Jan Lemstra
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-04 16:24
CPC Classifications
D; D01; D01F; D01F6/00; D01F6/28; D01F6/38; B; B29; B29D; B29D7/00; D01F6/02; D01F6/18; B29K; B29K2033/00; B29K2033/18; B29K2233/00; B29K2233/18
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
162 words
Process for preparing articles having a high tensile strength and a high modulus by converting a solution of polyacrylonitrile into a solvent containing article, cooling the articles formed and, stretching them at increased temperature, this process being characterized in that a. to a 0.5-15 % (wt) solution of polyacrylonitrile or a copolymer of acrylonitrile with at most 15 % (wt) comonomer with a weight-average molecular weight of 0.3 x 10 6 to 10 x 10 6 in a solvent suitable for that purpose a bivalent metal compound is added in a quantity of 0.01-0.2 mole per mole acrylonitrile units; b. the solution thus obtained is converted at increased temperature into a solvent containing article; c. this article is cooled to below the gelation temperature; d. the gel article thus formed is largely freed of solvent and metal compound; e. the article thus obtained is stretched at a temperature above the glass transition point of polyacrylonitrile and below the decomposition temperature of polyacrylonitrile.
Claim 2
Dependent Claim
162 words
Process for preparing articles having a high tensile strength and a high modulus by converting a solution of polyacrylonitrile into a solvent containing article, cooling the articles formed and, stretching them at increased temperature, this process being characterized in that a. to a 0.5-15 % (wt) solution of polyacrylonitrile or a copolymer of acrylonitrile with at most 15 % (wt) comonomer with a weight-average molecular weight of 0.3 x 10 6 to 10 x 10 6 in a solvent suitable for that purpose a bivalent metal compound is added in a quantity of 0.01-0.2 mole per mole acrylonitrile units; b. the solution thus obtained is converted at increased temperature into a solvent containing article; c. this article is cooled to below the gelation temperature; d. the gel article thus formed is largely freed of solvent and metal compound; e. the article thus obtained is stretched at a temperature above the glass transition point of polyacrylonitrile and below the decomposition temperature of polyacrylonitrile.
Claim 3
Dependent Claim
32 words
Process according to claim 1, characterized in that a 1-10 % (wt) solution of polyacrylonitrile having a weight-average molecular weight of 0.5 x 10 6 to 5 x 10 6 is used.
Claim 4
Dependent Claim
23 words
Process according to claim 1 or 2, characterized in that the bivalent metal compound used is a soluble salt of calcium or zinc.
Claim 5
Dependent Claim
31 words
Process according to any one of claims 1-3, characterized in that 0.02-0.1 mole zinc chloride per mole acrylonitrile units is added to a 3-7 % (wt) solution of polyacrylonitrile in dimethylformamide.
Claim 6
Dependent Claim
31 words
Process according to any one of claims 1-4, characterized in that the solvent containing article is cooled in a liquid medium in which the polyacrylonitrile does not dissolve, or hardly so.
Claim 7
Dependent Claim
20 words
Process according to claim 5, characterized in that the article is cooled in toluene, dichloromethane, water or mixtures of these.
Claim 8
Dependent Claim
24 words
Process according to any one of claims 1-6, characterized in that the gel article obtained during the cooling is treated in an evaporation zone.
Claim 9
Dependent Claim
36 words
Process according to any one of claims 1-6, characterized in that the gel article obtained during the cooling is subjected to extraction in a liquid medium at a temperature below the dissolving temperature of the gel.
Claim 10
Dependent Claim
22 words
Process according to claim 8, characterized in that the extraction medium used is dichloromethane, water or a mixture of water and dimethylformamide.
Claim 11
Dependent Claim
32 words
Process according to any one of claims 1-9, characterized in that the stretching is carried out at a temperature between 140 and 180 °C with a stretch ratio of at least 10.
Claim 12
Dependent Claim
20 words
Process according to any one of claims 1-10, characterized in that a stretch ratio of at least 20 is applied.
Claim 13
Dependent Claim
34 words
Process according to any one of claims 1-11, characterized in that the polyacrylonitrile solution is spun at a temperature between 90 and 150 °C through a spinning hole to form a filament or tape.
Claim 14
Dependent Claim
15 words
Articles obtainable while applying the process according to one or more of the preceding claims.
Claim 15
Dependent Claim
28 words
Filaments of polyacrylonitrile with a weight-average molecular weight of at least 0.3 x 10 6 having a tensile strength above 1.2 GPa and a modulus above 16 GPa.
Claim 16
Dependent Claim
28 words
Filaments of polyacrylonitrile with a weight-average molecular weight of at least 0.3 x 10 6 having a tensile strength above 1.2 GPa and a modulus above 16 GPa.
References Cited (Backward Citations)
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