Claims
- 1. A process for preparing a surfactant having the formula:
- R.sub.F C.sub.2 H.sub.4 S(R)H
- in which
- R designates a chain exclusively consisting of at least 2 identical or different units of the formula C.sub.2 H.sub.4 X wherein X=O or X=S and R.sub.F is a perfluorinated C.sub.2 -C.sub.12 alkyl group, comprising the steps of:
- (a) reacting a compound having the formula R.sub.F C.sub.2 H.sub.4 S(R')H wherein R' is a sulfur-hydrogen bond or a chain exclusively consisting of one or more identical or different units of C.sub.2 H.sub.4 X wherein X=O or X=S and X when bound to H is S, R' having at least one less C.sub.2 H.sub.4 X unit than does R and R.sub.F has the meaning given above, with ethylene or polyethylene glycol monochlorohydrin, in the presence of ethanol and sodium to obtain a first product having a terminal alcohol function; and
- where said first product has less C.sub.2 H.sub.4 X units than in R:
- (b) replacing the terminal alcohol function of the product of the previously performed step with a thiol function and reacting the thiol product resulting therefrom with ethylene or polyethylene glycol monochlorohydrin in the presence of ethanol and sodium; and
- (c) repeating step (b) upon the product thereof until said surfactant is obtained.
- 2. The method of claim 1, wherein the replacement of the alcohol function by a thiol function is performed by reacting said product with thiourea in the presence of HBr.
- 3. The method of claim 1, wherein said first product has less C.sub.2 H.sub.4 X units than in R.
Priority Claims (1)
Number |
Date |
Country |
Kind |
84 08376 |
May 1984 |
FRX |
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Parent Case Info
This application is a continuation of application Ser. No. 738,701 filed May 29, 1985, now abandoned.
US Referenced Citations (5)
Foreign Referenced Citations (3)
Number |
Date |
Country |
2856616 |
Jul 1979 |
DEX |
2111253 |
Jun 1972 |
FRX |
2416222 |
Aug 1979 |
FRX |
Non-Patent Literature Citations (1)
Entry |
Derwent Abstract of French patent No. 2,516,920, published 05/1983 (Inst. Nat.). |
Continuations (1)
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Number |
Date |
Country |
Parent |
738701 |
May 1985 |
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