EP0142894A2
Expired / Lapsed
EP
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Process for purifying a rubber
Assignee: DSM BV
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Filing: 1984-11-14
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Granted: —
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Expires: 2004-11-14
Abstract
Abstract The invention relates to a process for purifying ethylene-alkene-diene rubbers by extraction with an extractant chosen from substances with a critical temperature below 435 °K at a temperature above the critical temperature of the extractant and a pressure above the critical pressure of the extractant.
Inventors
- 👤 Ludovicus Anna Leonard Kleintjens
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-06 14:28
CPC Classifications
C; C08; C08F; C08F6/00; C08F6/14; C08F6/16
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
80 words
Process for purifying a rubber consisting of at least groups derived from ethylene, from alkene-1 having 3-8 C atoms per group and from diene characterized in that, per kg impurities in the rubber, the rubber is treated with at least 20 Nm 3 (NPT) of an extractant chosen from substances the critical temperatures of which are lower than 435 K, at a temperature above the critical temperature of the extractant and a pressure above the critical pressure of the extractant.
Claim 2
Dependent Claim
80 words
Process for purifying a rubber consisting of at least groups derived from ethylene, from alkene-1 having 3-8 C atoms per group and from diene characterized in that, per kg impurities in the rubber, the rubber is treated with at least 20 Nm 3 (NPT) of an extractant chosen from substances the critical temperatures of which are lower than 435 K, at a temperature above the critical temperature of the extractant and a pressure above the critical pressure of the extractant.
Claim 3
Dependent Claim
38 words
Process according to claim 1, characterized in that, before the treatment with the said extractant, the rubber to be purified is freed from water to a water content lower than 5 % (wt) in respect of the rubber.
Claim 4
Dependent Claim
24 words
Process according to claims 1 and 2, characterized in that the treatment with the extractant is made to last 1 minute - 5 hours.
Claim 5
Dependent Claim
31 words
Process according to any one of claims 1-3, characterized in that the treatment with the extractant is effected at a temperature between the critical temperature of the extractant and 600 K.
Claim 6
Dependent Claim
34 words
Process according to any one of claims 1-4, characterized in that the treatment with the extractant is effected at a pressure between the critical pressure and 10 times the critical pressure of the extractant.
Claim 7
Dependent Claim
26 words
Process according to any one of claims 1-5, characterized in that per kg impurities in the rubber 40 - 1500 Nm 3 (NPT) extractant is used.
Claim 8
Dependent Claim
31 words
Process according to any one of claims 1-6, characterized in that the extractant used is C0 2 , ethylene, propylene or a mixture of two or all three of these components.
Claim 9
Dependent Claim
15 words
Process according to claim 7, characterized in that the extractant used is C0 2 .
Claim 10
Dependent Claim
21 words
Process according to claim 8, characterized in that the extractant used is ethylene, propylene or a mixture of these two components.
Claim 11
Dependent Claim
17 words
Process as described in substance in the text and elucidated by the examples and the comparative experiments.
Claim 12
Dependent Claim
17 words
Process as described in substance in the text and elucidated by the examples and the comparative experiments.
References Cited (Backward Citations)
No citation records indexed.
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