SOLVENT SYSTEM COMPRISING A MIXTURE OF DIMETHYL SULFOXIDE AND AT LEAST ONE LACTONE

Abstract

Provided is a solvent system containing from 5% to 95% by weight of a composition (A) containing dimethyl sulfoxide (DMSO), with respect to the total weight of the solvent system and from 5% to 95% by weight of a composition (B) comprising at least one lactone, with respect to the total weight of the solvent system. The solvent system has a variety of uses and is highly effective in dissolving polymer materials.

Claims

1. A solvent system comprising: from 5% to 95% by weight of a composition (A) comprising dimethyl sulfoxide (DMSO), with respect to the total weight of the solvent system; and from 5% to 95% by weight of a composition (B) comprising at least one lactone, with respect to the total weight of the solvent system.

2. The solvent system as claimed in claim 1, in which said lactone comprises from 4 to 12 carbon atoms, said lactone being saturated or unsaturated and optionally substituted by one or more C.sub.1-C.sub.10 alkyl chains.

3. The solvent system as claimed in claim 1, in which said lactone is chosen from ?-butyrolactone, ?-pentalactone, ?-hexalactone, ?-octalactone, ?-octalactone, ?-decalactone, ?-decalactone, ?-dodecalactone, ?-dodecalactone, ?-amyl-?-pyrone, ?-valerolactone, ?-valerolactone, ?-caprolactone, coumarin and ascorbic acid.

4. The solvent system as claimed in claim 1, in which said lactone or the mixture of lactones exhibits a boiling point of between 150 and 250? C.

5. The solvent system as claimed in claim 1, in which said lactone is soluble in water.

6. The solvent system as claimed in claim 1, in which said solvent system comprises from 5% to 80% by weight of a composition (A) with respect to the total weight of the solvent system.

7. The solvent system as claimed in claim 1, in which said system comprises from 20% to 95% by weight of a composition (B) with respect to the total weight of the solvent system.

8. The solvent system as claimed in claim 1, in which said system comprises from 0% to 20% by weight of one or more additional solvent(s), with respect to the total weight of the solvent system.

9. The solvent system as claimed in claim 8, in which said additional solvent exhibits a boiling point of between 150 and 250? C.

10. The solvent system as claimed in claim 8, in which said additional solvent is soluble in water.

11-12: (canceled)

13. A process for dissolution of a fluoropolymer or of a polymer comprising at least one X?O double bond, X being chosen from the sulfur atom, the carbon atom, an NC group and an OC group, comprising at least one stage in which said polymer is brought into contact with at least one solvent system as defined in claim 1.

14. A solution comprising: from 1% to 50% by weight of at least one fluoropolymer or one polymer comprising at least one X?O double bond, X being chosen from the sulfur atom, the carbon atom, an NC group and an OC group, with respect to the total weight of the solution, and from 50% to 99% by weight, with respect to the total weight of the solution, of at least one solvent system as defined in claim 1.

15. (canceled)

16. The process as defined in claim 13, wherein the polymer comprising at least one X?O double bond comprises at least one member selected from the group consisting of polyurethanes, polyethersulfones, polysulfones, poly(vinylidene fluoride)s, cellulose acetates, polyesters, polyamides, polyamide-imides, and polyimides.

17. A method of preparing the solvent system as defined in claim 1 comprising combining composition (A) and composition (B).

18. A method of manufacturing a film, artificial leather, polymer suede, polymer fiber, coating, membrane, electric cable, battery or electronic circuit, comprising incorporating the solvent system as defined in claim 1 into the film, artificial leather, polymer suede, polymer fiber, coating, membrane, electric cable, battery or electronic circuit.

19. A method of preparing the solution as defined in claim 14 comprising combining the fluoropolymer or polymer comprising at least one X?O double bond and the solvent system.

20. A method of manufacturing a film, artificial leather, polymer suede, polymer fiber, coating, membrane, electric cable, battery or electronic circuit, comprising incorporating the solution as defined in claim 14 into the film, artificial leather, polymer suede, polymer fiber, coating, membrane, electric cable, battery or electronic circuit.

21. The method of claim 20, further comprising removing the solvent system.

Description

EXAMPLES

Example 1: Solution Comprising Polyurethane and a DMSO/GBL Solvent System

[0085] a) Solubility Test at T=70? C. and at Ambient Temperature

[0086] 12.5% by weight of Desmoderm? KB2H polyurethane are introduced into different solvent systems comprising DMSO and ?-butyrolactone (GBL), with respect to the total weight of the solution formed by the polymer and the solvent system.

[0087] The mixture is heated to 70? C. with gentle stirring. The solubility of the solutions tested is evaluated.

[0088] The solutions are cooled to ambient temperature and the appearance of the solutions tested is evaluated.

[0089] The results are presented in table 1:

TABLE-US-00001 TABLE 1 Appearance of the Solution comprising Solvent system solution after 12.5% by weight (% by weight) Solubility at returning to of PU DMSO GBL 70? C. ambient temperature A 100 Yes Fluid (comparative) B 65 35 Yes Fluid (invention) C 50 50 Yes Fluid (invention) D 100 No dissolution observed (comparative)

[0090] After a few hours, the polymer is completely dissolved, except in the case of the solution D. Fluid solutions are obtained for the solutions A to C.

[0091] It is also found that the solutions A to C exhibit a fluid appearance after they have been cooled to ambient temperature.

[0092] b) Solubility Test at T=?2? C.

[0093] The solutions are subsequently stored at low temperature (?2? C.) for several days in order to observe their stability over time.

[0094] The results are presented in table 2:

TABLE-US-00002 TABLE 2 Solution Time from which gelling of the solution is observed A (comp.) 2 hours B (inv.) Solution fluid after 6 days C (inv.) Solution fluid after 6 days D (comp.) No dissolution observed during test a)

[0095] Thus, it is found that the solution A exhibits a solid appearance only two hours after it has been stored at a temperature of ?2? C. This is because the solution gels very rapidly.

[0096] On the other hand, the solutions B and C still exhibit a fluid appearance after storage at this temperature for 6 days. The solution is thus stable for at least 6 days.

[0097] Thus, the solvent system according to the invention exhibits an improvement in the stability of the polymer solution, thus showing a surprising advantage in using these two solvents as a mixture.

Example 2: Solution Comprising Polyurethane and a DMSO/GVL Solvent System

[0098] a) Solubility Test at T=70? C. and at Ambient Temperature

[0099] 12.5% by weight of Desmoderm? KB2H polyurethane are introduced into different solvent systems comprising DMSO and ?-valerolactone (GVL), with respect to the total weight of the solution formed by the polymer and the solvent system.

[0100] The mixture is heated to 70? C. with gentle stirring. The solubility of the solutions tested is evaluated.

[0101] The solutions are cooled to ambient temperature and the appearance of the solutions tested is evaluated.

[0102] The results are presented in table 3:

TABLE-US-00003 TABLE 3 Appearance of the Solution comprising Solvent system solution after 12.5% by weight (% by weight) Solubility at returning to of PU DMSO GVL 70? C. ambient temperature E 100 Yes Fluid (comparative) F 50 50 Yes Fluid (invention) G 30 70 Yes Fluid (invention) H 100 No dissolution observed (comparative)

[0103] After a few hours, the polymer is completely dissolved, except in the case of the solution H. Fluid solutions are obtained for the solutions E to G.

[0104] It is also found that the solutions E to G exhibit a fluid appearance after they have been cooled to ambient temperature.

[0105] b) Solubility Test at T=?2? C.

[0106] The solutions are subsequently stored at low temperature (?2? C.) for several days in order to observe their stability over time.

[0107] The results are presented in table 4:

TABLE-US-00004 TABLE 4 Solution Time from which gelling of the solution is observed E (comp.) Solution set solid after 1 week F (inv.) Solution stable after 1 week G (inv.) Solution stable after 1 week H (comp.) No dissolution observed during test a)

[0108] Thus, it is found that the solution E exhibits a set-solid appearance only one week after it has been stored at a temperature of ?2? C.

[0109] Other the other hand, the solutions F and G remain stable after storage at a temperature of ?2? C.

[0110] Thus, the solvent system according to the invention exhibits an improvement in the stability of the polymer solution, thus showing a surprising advantage in using these two solvents as a mixture.

Example 3: Solution Comprising Polyvinylidene Fluoride and a DMSO/GVL Solvent System

[0111] a) Solubility Test at T=70? C. and at Ambient Temperature

[0112] 10% by weight of Kynar? K761 polyvinylidene fluoride are introduced into different solvent systems comprising DMSO and ?-valerolactone (GVL), with respect to the total weight of the solution formed by the polymer and the solvent system.

[0113] The mixture is heated to 70? C. with gentle stirring. The solubility of the solutions tested is evaluated.

[0114] The solutions are cooled to ambient temperature and the appearance of the solutions tested is evaluated.

[0115] The results are presented in table 5:

TABLE-US-00005 TABLE 5 Appearance of the Solution comprising Solvent system solution after 10% by weight (% by weight) Solubility at returning to of PVDF DMSO GVL 70? C. ambient temperature I 100 Yes Fluid (comparative) J 80 20 Yes Fluid (invention) K 50 50 Yes Fluid (invention) L 100 No dissolution observed (comparative)

[0116] After a few hours, the polymer is completely dissolved, except in the case of the solution L. Fluid solutions are obtained for the solutions I to K.

[0117] It is also found that the solutions I to K exhibit a fluid appearance after they have been cooled to ambient temperature.

[0118] b) Solubility Test at Ambient Temperature Over Time

[0119] The solutions are subsequently stored at ambient temperature for several days in order to observe their stability over time.

[0120] The results are presented in table 6:

TABLE-US-00006 TABLE 6 Time from which cloudiness of Solution the solution is observed I (comp.) Solution clouded after 1 week J (inv.) Solution colorless/transparent after 2 weeks K (inv.) Solution slightly clouded after 2 weeks L (comp.) No dissolution observed during test a)

[0121] Thus, it is found that the solution I exhibits a clouded appearance only one week after it has been stored at ambient temperature.

[0122] On the other hand, the solution K exhibits a slightly clouded appearance two weeks after it has been stored at ambient temperature.

[0123] Finally, the solution J still exhibits a colorless and transparent appearance after storage for two weeks.

[0124] Thus, the solvent system according to the invention exhibits an improvement in the stability of the polymer solution, thus showing a surprising advantage in using these two solvents as a mixture.

Example 4: Solution Comprising a Polyethersulfone and a DMSO/GBL Solvent System

[0125] a) Solubility Test at T=70? C. and at Ambient Temperature

[0126] 15% by weight of Ultrason? E3010 polyethersulfone are introduced into different solvent systems comprising DMSO and ?-butyrolactone (GBL), with respect to the total weight of the solution formed by the polymer and the solvent system.

[0127] The mixture is heated to 70? C. with gentle stirring. The solubility of the solutions tested is evaluated.

[0128] The solutions are cooled to ambient temperature and the appearance of the solutions tested is evaluated.

[0129] The results are presented in table 7:

TABLE-US-00007 TABLE 7 Appearance of the Solution comprising Solvent system solution after 15% by weight (% by weight) Solubility at returning to of PES DMSO GBL 70? C. ambient temperature M 100 Yes Liquid (comparative) N 65 35 Yes Liquid (invention) O 50 50 Yes Liquid (invention) P 100 Yes Solid after 1 week (comparative)

[0130] After a few hours, the polymer is completely dissolved and a fluid solution is obtained for all the solutions M to P.

[0131] It is also found that the solutions M to O exhibit a fluid appearance after they have been cooled to ambient temperature for several weeks. On the other hand, the solution P exhibits a solid appearance at ambient temperature after one week.

[0132] b) Solubility Test at T=?2? C.

[0133] The solutions are subsequently stored at low temperature (?2? C.) for several days in order to observe their stability over time.

[0134] The results are presented in table 8:

TABLE-US-00008 TABLE 8 Time from which gelling of the solution is observed M (comp.) 2 hours N (inv.) Solution still liquid after 3 weeks O (inv.) Solution still liquid after 1 week P (comp.) ?15 minutes

[0135] Thus, it may be found that the solution M exhibits a solid appearance only two hours after it has been stored at a temperature of ?2? C. This is because the solution gels very rapidly.

[0136] Furthermore, the solution P very rapidly exhibits a solid appearance at ambient temperature.

[0137] On the other hand, the solution O exhibits an appearance which is still liquid one week after it has been stored at a temperature of ?2? C.

[0138] Finally, the solution N still exhibits a liquid appearance three weeks after it has been stored at a temperature of ?2? C.

[0139] Thus, the solvent system according to the invention exhibits an improvement in the stability of the polymer solution, thus showing a surprising advantage in using these two solvents as a mixture.

Example 5: Solution Comprising a Polysulfone and a DMSO/GVL Solvent System

[0140] a) Solubility Test at T=70? C. and at Ambient Temperature

[0141] 10% by weight of Solvay Udel? P-3500 polysulfone (PSU) are introduced into different solvent systems comprising DMSO and ?-valerolactone (GVL), with respect to the total weight of the solution formed by the polymer and the solvent system.

[0142] The mixture is heated to 70? C. with gentle stirring. The solubility of the solutions tested is evaluated.

[0143] The solutions are cooled to ambient temperature and the appearance of the solutions tested is evaluated.

[0144] The results are presented in table 9:

TABLE-US-00009 TABLE 9 Appearance of the Solution comprising Solvent system solution after 10% by weight (% by weight) Solubility at returning to of PSU DMSO GVL 70? C. ambient temperature Q 100 Yes Gelled (comparative) R 50 50 Yes Fluid (invention) S 30 70 Yes Fluid (invention) T 100 Yes Fluid (comparative)

[0145] After a few hours, the polymer is completely dissolved and a fluid solution is obtained for all the solutions Q to T.

[0146] It is also found that the solutions R to T exhibit a fluid appearance after they have been cooled to ambient temperature, except for the solution Q, which exhibits a gelled appearance.

[0147] b) Solubility Test at T=?2? C.

[0148] The solutions are subsequently stored at low temperature (?2? C.) for several days in order to observe their stability over time.

[0149] The results are presented in table 10:

TABLE-US-00010 TABLE 10 Solution Time from which gelling of the solution is observed Q (comp.) Solution gelled at ambient temperature R (inv.) Solution slightly viscous after 1 week S (inv.) Solution fluid after 3 weeks T (comp.) Solution set solid after 1 week

[0150] Thus, it is found that the solution T exhibits a set-solid appearance only one week after it has been stored at a temperature of ?2? C.

[0151] On the other hand, the solution R exhibits a viscous appearance one week after it has been stored at a temperature of ?2? C.

[0152] Finally, the solution S still exhibits a fluid appearance one week after it has been stored at a temperature of ?2? C., it additionally being possible for this fluid appearance to still be observed after storage for three weeks.

[0153] Thus, the solvent system according to the invention exhibits an improvement in the stability of the polymer solution, thus showing a surprising advantage in using these two solvents as a mixture.