Fluorinated unsaturated compound and polymers obtainable therefrom

Abstract

A compound of formula CF.sub.2CFCF.sub.2OSF.sub.5 and polymers comprising recurring units deriving from CF.sub.2CFCF.sub.2OSF.sub.5 are disclosed as well as processes for their preparation.

Claims

1. A compound of formula CF.sub.2CFCF.sub.2OSF.sub.5.

2. Process for the preparation of the compound of claim 1 comprising reacting SOF.sub.4 with CF.sub.2CFCF.sub.2OSO.sub.2F in the presence of a fluoride catalyst.

3. A polymer comprising recurring units derived from CF.sub.2CFCF.sub.2OSF.sub.5.

4. Polymer according to claim 3 further comprising recurring units derived from at least one ethylenically unsaturated monomer.

5. Polymer according to claim 4 wherein the ethylenically unsaturated monomer is selected from a fluorinated monomer and/or a non-fluorinated monomer.

6. Polymer according to claim 5 wherein the fluorinated monomer is selected from the group consisting of: C.sub.2-C.sub.8 fluorofluoroolefins; C.sub.2-C.sub.8 hydrogenated fluoroolefins; fluoroalkylethylenes of formula CH.sub.2CHR.sub.m, wherein R.sub.f0 is a C.sub.1-C.sub.6 fluoroalkyl or a C.sub.1-C.sub.6 fluorooxyalkyl having one or more ether groups; chloro- and/or bromo- and/or iodo-C.sub.2-C.sub.6 fluoroolefins; fluoroalkylvinylethers of formula CF.sub.2CFOR.sub.f1 in which R.sub.f1 is a C.sub.1-C.sub.6 fluoroalkyl; hydrofluoroalkylvinylethers of formula CH.sub.2CFOR.sub.f1 in which R.sub.f1 is a C.sub.1-C.sub.6 fluoroalkyl; fluorooxyalkylvinylethers of formula CF.sub.2CFOR.sub.O1, in which R.sub.O1 is a C.sub.1-C.sub.12 alkyl or a C.sub.1-C.sub.12 fluoroalkyl having one or more ether groups; fluoroalkyl-difluoromethoxy-vinylethers of formula CF.sub.2CFOCF.sub.2OR.sub.f2 in which R.sub.f2 is a C.sub.1-C.sub.6 fluoroalkyl or a C.sub.1-C.sub.6 fluoroalkyloxyl having one or more ether groups; functional fluoro-alkylvinylethers of formula CF.sub.2CFOY.sub.0, in which Y.sub.0 is a C.sub.1-C.sub.12 alkyl or fluoroalkyl, or a C.sub.1-C.sub.12 alkyloxy, or a C.sub.1-C.sub.12 fluoroalkyloxyl, said Y.sub.0 group having one or more ether groups and Y.sub.0 comprising a carboxylic or sulfonic acid group, in its acid, acid halide or salt form; and fluorodioxoles of formula: ##STR00003## wherein each of R.sub.f3, R.sub.f4, R.sub.f5, R.sub.f6, equal or different each other, is independently a fluorine atom, a C.sub.1-C.sub.6 fluoro- or (halo)fluoroalkyl, optionally comprising one or more oxygen atom.

7. Polymer according to claim 5 wherein the non-fluorinated monomer is selected from the group consisting of: C.sub.2-C.sub.8 olefins; C.sub.2-C.sub.8 chloroolefins; acrylic- or methacrylic monomers of formula CH.sub.2=CR.sub.h1R.sub.h2 in which R.sub.h1 is chosen from hydrogen and the methyl group and R.sub.h2 is the COR.sub.h3 group in which R.sub.h3 is chosen from the OH group and the OR.sub.h4 groups with R.sub.h4 chosen from the linear or branched alkyl groups containing from 2 to 18 carbon atoms optionally bearing one or more OH group.

8. Polymer according to claim 4 wherein the ethylenically unsaturated monomer is a fluorinated monomer selected from tetrafluoroethylene, hexafluoropropylene, vinylidene fluoride, trifluoroethylene, and fluoroalkylvinylethers of formula CF.sub.2CFOR.sub.f1 wherein R.sub.f1 is CF.sub.3, C.sub.2F.sub.5, or C.sub.3F.sub.7.

9. Polymer according to claim 4, wherein the polymer comprises recurring units derived from CF.sub.2CFCF.sub.2OSF.sub.5 and recurring units derived from tetrafluoroethylene.

10. Polymer according to claim 9, wherein the polymer further comprises recurring units derived from hexafluoropropylene.

11. Polymer according to claim 4, wherein the polymer comprises recurring units derived from CF.sub.2CFCF.sub.2OSF.sub.5 and recurring units derived from vinylidene fluoride.

12. Polymer according to claim 11, wherein the polymer further comprises recurring units derived from hexafluoropropylene.

13. Polymer according to claim 3, wherein the amount of recurring units derived from CF.sub.2CFCF.sub.2OSF.sub.5 ranges from 0.1 to 99.9 mole %.

14. Process for the preparation of a polymer of claim 3 comprising the step of polymerizing the compound of formula CF.sub.2CFCF.sub.2OSF.sub.5 and optionally at least one ethylenically unsaturated monomer in the presence of a polymerization initiator.

15. Process according to claim 14 wherein the polymerization initiator is a radical polymerization initiator.

16. An article comprising the polymer of claim 3.

Description

EXAMPLES

Raw Materials

(1) Fluoroallyl fluorosulfate was synthesized according to previously described techniques (KRESPAN, G, et al. Perfluoroallylfluorosulfate, a reactive new perfluoroallylating agent. J. Am. Chem. Soc. 1981, vol. 103, p. 5598-5599.) and obtained with a selectivity of 80% (on converted SO.sub.3) as a fluid having boiling point of 64 C.

(2) Characterization

(3) NMR: spectra were recorded on a Varian Inova 400 spectrometer operating at 376.198 MHz for .sup.19F and a Varian S 500 MHz spectrometer operating at 470.300 MHz for .sup.19F and 125.70 MHz for .sup.13C. .sup.19F NMR and .sup.13C NMR spectra of the monomer were recorded in acetone at room temperature and the spectra was referenced to CFCl.sub.3. .sup.19F NMR of the polymers were recorded in C.sub.6F.sub.6 at 60 C. and the spectra were referenced to the solvent (C.sub.6F.sub.6, 164.67 ppm).

(4) Wurzschmitt Digestion

(5) About 50 mg of the polymer sample was mixed with 0.2 g of ethylene glycol, 6 g of sodium peroxide and 0.2 g of sodium carbonate. The mixture was heated up with a flame in a closed combustion device (Wurzschmitt bomb) for 1 h 30. After cooling the residue was dissolved in 200 ml of distilled water, boiled and allowed to cool down again. After appropriate dilution the solution was subjected to the analysis by ionic chromatography in order to determine quantitatively the sulphur content of the polymer.

(6) An ion chromatograph (ICS3000 DIONEX) with an ion-exchange column (AS 14A), a suppressor (ASRS 300) and a conductivity detector was used. The mobile phase consisted of 8 mM sodium carbonate and 1 mM sodium bicarbonate. The flow rate was 1 ml/min.

(7) Transition temperatures (Melting and Glass transition temperature) were determined by DSC at a heating rate of 20 C./min following the procedure of ASTM D3418-08.

(8) Weight Loss Determination

(9) The weight loss determination at 200 C. was carried out using a TGA PYRIS 1 equipment from Perkin-Elmer according to method ASTM E 1131. A 10 mg sample of the polymer was subjected to constant heating in air at a rate of 10 C./min from 23 C. up to 750 C. The temperature at which 2% and 10% weight loss are measured is given.

Example 1

Synthesis of CF2CFCF2OSF5 (I)

(10) In an AlS1-316 reactor having 300 ml volume, equipped with magnetic stirring, was charged 9.3 g of previously dried KF and 100 ml of anhydrous diethylenglycol diethylether. The reactor was evacuated at reduced pressure, cooled at 196 C. before introducing 22.3 g of SOF.sub.4. The reactor was warmed at 0 C. under stirring, cooled again at 196 C. and 35 g of fluoroallyl fluorosulfate was charged. The reactor mixture was allowed to return to 0 C. and kept at 0 C. for 3.5 h under vigorous stirring, then at 20 C. for another 0.5 h. The reactor was connected to two consecutive traps maintained at 78 C., opened and evacuated at reduced pressure. 43.1 g of crude product were collected in the two traps. After distillation in a Spalthror Fischer apparatus (60 lates efficiency) 30 g of CF.sub.2CFCF.sub.2OSF.sub.5 (I) were collected with a purity of 99.5%.

(11) .sup.19F NMR(CFCl.sub.3 reference): +70.5 ppm (m; 4F; FSF.sub.4); +63.2 ppm (m; 1F; FSF.sub.4); 74.3 ppm (ddqd; 2F; OCF.sub.2); 91.2 ppm (ddt; 1F; CF.sub.2CF); 104.5 ppm (ddt; 1F; CF.sub.2CF); 192.8 ppm (ddt; 1F; CF.sub.2CF).

(12) .sup.13C NMR: 154.7 ppm (td; 1C; CF.sub.2CF); 121.8 ppm (m; 1C; CF.sub.2CF); 117.2 ppm (td; 1C; OCF.sub.2).

Example 2

Polymer Comprising Recurring Units of (I) and Vinylidene Fluoride (CH2CF2)Bulk Polymerization

(13) In an AISI-316 reactor having 45 ml volume, equipped with magnetic stirring, 300 l of perfluoropropionylperoxide (0.098M in CF.sub.3OCFClCF.sub.2Cl), 8.98 mmoles of (I) and 14.06 mmoles of vinylidene fluoride were introduced. The reactor was evacuated at 196 C., and then brought to room temperature. The cooling-evacuation procedure was repeated twice. At the end of the degassing procedure the reactor was maintained at 25 C. under stirring. The internal pressure decreased from 0.69 MPa to 0.23 MPa (in about 70 hours). After distillation of the unreacted monomers, the polymer was treated at 150 C. under vacuum for three hours and 2.56 g of a transparent and colourless polymer were obtained.

(14) .sup.19F-NMR analysis carried out at 60 C. on the polymer dissolved in C.sub.6F.sub.6 showed the following signals: +72.5 ppm (FSF4); +60.5 ppm (FSF.sub.4); 80 ppm (CF.sub.2OSF.sub.5); 90/120 ppm (RfCF.sub.2Rf; RfCF.sub.2Rh; RhCF.sub.2Rh); 182 ppm (CF.sub.2CF(CF.sub.2OSF.sub.5)Rf).

(15) The molar percentage of CF.sub.2CFCF.sub.2OSF.sub.5 in the polymer as determined by NMR was determined to be 36 mole %.

(16) The polymer was analyzed also with the Wurzschmitt digestion according to the procedure described above. The molar percentage of CF.sub.2CFCF.sub.2OSF.sub.5 in the polymer obtained from this method was determined to be 35 mole %.

Example 3

Polymer Comprising Recurring Units of (I) and Vinylidene Fluoride (VDF)Emulsion Polymerization

(17) In the reactor of Example 2, 4.8 g of an emulsion prepared with distilled water, Fluorolink PFPE monocarboxylate ammonium salt (FLK 7850) (7% by weight) and 0.0211 g of ammonium persulfate, 5.33 mmoles of (I) and 27.27 mmoles of VDF were sequentially introduced. The reactor was cooled to 196 C., evacuated, and then allowed to return to room temperature. The cooling-evacuation procedure was repeated twice. At the end of the degassing procedure the reactor temperature was brought to 65 C. and held at the same temperature for 19 hours under stirring while the internal pressure was allowed to decrease from 1.03 MPa to 0 MPa. The reactor was cooled down to room temperature, the emulsion discharged and coagulation induced by addition of concentrated HNO.sub.3 (65%). The polymer was separated from the liquid phase, washed with distilled water, treated at 150 C. under vacuum for three hours: 2.10 g of a solid polymer were isolated.

(18) .sup.19F-NMR analysis carried out at 60 C. on the polymer dissolved in C.sub.6F.sub.6 showed the following signals: +72.5 ppm (FSF.sub.4); +60.5 ppm (FSF.sub.4); 80 ppm (CF.sub.2OSF.sub.5); 90/120 ppm (RfCF.sub.2Rf; RfCF.sub.2Rh; RhCF.sub.2Rh); 182 ppm (CF.sub.2CF(CF.sub.2OSF.sub.5)Rf). The molar percentage, determined by NMR analysis, of CF.sub.2CFCF.sub.2OSF.sub.5 in the polymer was determined to be 16.7 mole %.

Example 4

Polymer Comprising Recurring Units of (I) and Tetrafluoroethylene (TFE)Bulk Polymerization

(19) Following the same procedure of Example 2, 300 l of perfluoropropionylperoxide (0.098M in CF.sub.3OCFClCF.sub.2Cl) and 8.76 mmoles of (I) were sequentially introduced into the reactor. At the end of the degassing procedure 19.6 mmoles of TFE were introduced. The reactor temperature was maintained at 25 C. and the internal pressure was allowed to decrease from 0.95 MPa bar to 0.27 MPa bar (in about 50 hours). 2.02 g of a white crystalline polymer were obtained.

(20) Due to the low solubility, the polymer was analyzed with the Wurzschmitt digestion. The molar percentage of CF.sub.2CFCF.sub.2OSF.sub.5 in the polymer was determined to be 5 mole %.

Example 5

Polymer Comprising Recurring Units of (I) and Tetrafluoroethylene (TFE)Emulsion Polymerization

(21) Following the same procedure of Example 3, 3.5 g of an emulsion prepared with distilled water, Fluorolink PFPE monocarboxylate ammonium salt (FLK 7850) (7% by weight), 0.0132 g of ammonium persulfate and 3.25 mmoles of (I) were sequentially introduced in the reactor. At the end of the degassing procedure 9.9 mmoles of TFE were introduced. The internal pressure was allowed to decrease from 0.40 MPa to 0.05 MPa (about 21 hours). The reactor was cooled at room temperature and the solid recovered as described in Example 3, providing 0.80 g of a solid polymer.

(22) Due to the low solubility, the polymer was analyzed with the Wurzschmitt digestion. The molar percentage of CF.sub.2CFCF.sub.2OSF.sub.5 in the polymer was determined to be 16 mole %.

Example 6

Polymer Comprising Recurring Units of (I), Vinylidene Fluoride (VDF) and Hexafluoropropylene (HFP)

(23) Following the same procedure of Example 3, 11.8 g of an emulsion prepared with distilled water, Fluorolink PFPE monocarboxylate ammonium salt (FLK 7850) (7% by weight), 0.033 g of ammonium persulfate, 5.55 mmoles of (I), 16.42 mmoles of VDF and 5.47 mmoles of HFP were sequentially introduced in the reactor. At the end of the degassing procedure the reactor temperature was brought to 65 C. and the internal pressure allowed decreasing from 0.68 MPa to 0 MPa (about 22 hours). The reactor was cooled to room temperature and the solid recovered as described in Example 3, providing 3.23 g of a white rubbery material.

(24) .sup.19F-NMR analysis carried out at 60 C. on the polymer dissolved in C.sub.6F.sub.6 showed the following signals: +72.5 ppm (FSF.sub.4); +60.5 ppm (FSF.sub.4); 70/76 ppm (CF.sub.2CF(CF.sub.3)Rh; CF.sub.2CF(CF.sub.3)Rf); 80 ppm (CF.sub.2OSF.sub.5); 90/120 ppm (RfCF.sub.2Rf; RfCF.sub.2Rh; RhCF.sub.2Rh); 182 ppm (CF.sub.2CF(CF.sub.2OSF.sub.5)Rf; CF.sub.2CF(CF.sub.3)Rf).

(25) The molar percentage of each monomer in the polymer was determined by NMR analysis with the following results: CF.sub.2CFCF.sub.2OSF.sub.5: 20.4 mole %, VDF: 59.7 mole %, HFP: 19.9 mole %.

(26) The properties of the polymers of Examples 2-6 are reported in Table 1.

(27) TABLE-US-00001 TABLE 1 Melting temp. 2% 10% Monomer (mole %) (2.sup.nd heating) weight weight Ex. (I) VDF TFE HFP ( C.) loss ( C.) loss ( C.) 2 36 64 427 444 3 16.7 83.3 130 398 443 4 5 95 275-323 456 487 5 16 84 409 451 6 20.4 59.7 19.9 403 443

(28) Polymers comprising recurring units deriving from (I) and VDF may be both amorphous (Example 2) and semi-crystalline (Example 3).

(29) The same has been observed for polymers comprising recurring units deriving from (I) and TFE (Examples 5 and 4 respectively).

(30) All the polymers obtained are stable at high temperatures with a weight loss of less than 2 wt % up to about 400 C. and less than 10% up to about 450 C.