Method for making polyetherimides

• US 20070073035A1
• Filed: 11/21/2006
• Published: 03/29/2007
• Est. Priority Date: 09/23/2005
• Status: Active Grant

• Current Assignee: SHPP Global Technologies BV
• Original Assignee: General Electric Company
• Inventors: Hall, David, Stella, Albert
• Granted Patent: US 7,411,032 B2
• Time in Patent Office: Days
• US Class Current: 528/350
• CPC Class Codes: C07C 51/573 Separation; Purification; Stabilisation; Use of additives
• CPC Class Codes: C07C 65/24 polycyclic
• CPC Class Codes: C08G 73/1007 from tetracarboxylic acids or derivatives and diamines
• CPC Class Codes: C08G 73/1014 in the form of (mono)anhydrid
• CPC Class Codes: C08G 73/1028 characterised by the process itself, e.g. steps, continuous
• CPC Class Codes: C08G 73/105 with oxygen only in the diamino moiety

Abstract

A method for making polyetherimides is provided by reacting a high purity dianhydride with an aromatic diamine under condensation polymerization conditions. The dianhydrides employed are purified by a method comprising contacting a first solution containing a dianhydride compound, a solvent, and a phase transfer catalyst, with a solid inorganic adsorbent material having a total pore volume of about 0.5 milliliters/gram or greater and a cumulative pore volume distribution of about 20 percent or greater of particles having a pore diameter in a range between about 3 nanometers and about 20 nanometers. The solution containing the dianhydride compound is then separated from the solid inorganic adsorbent material to provide a purified dianhydride compound which is substantially free of the phase transfer catalyst. The purified dianhydrides are then condensed with aromatic diamines to provide polyetherimide compositions which are substantially free of residual phase transfer catalyst.

Claims

1. A method of preparing a polyetherimide, said method comprising reacting at least one aromatic diamine with a purified dianhydride, said purified dianhydride having been purified by a method, said method comprising the steps of:

a. providing a first solution comprising at least one dianhydride, at least one solvent, and at least one organic phase transfer catalyst; and

b. contacting the first solution with a solid inorganic adsorbent material, said solid inorganic adsorbent material having a total pore volume of about 0.5 milliliters/gram or greater, and a cumulative pore volume distribution of about 20 percent or greater of particles having a pore diameter in a range between about 3 nanometers and about 20 nanometers;

to provide a second solution of the dianhydride, which is substantially free of the organic phase transfer catalyst.

2. A method of preparing a polyetherimide, said method comprising reacting at least one aromatic diamine with a purified oxybisphthalic anhydride, said purified oxybisphthalic anhydride having structure (IV)

3. The method of claim 2, wherein said contacting is carried out at a temperature in a range between about 50°

C. and about 250°

C.

4. The method of claim 2, further comprising crystallizing the oxybisphthalic anhydride (IV) from the second solution to provide a purified slurry of oxybisphthalic anhydride containing less than about 150 parts per million of an organic phase transfer catalyst.

5. The method according to claim 2, wherein the oxybisphthalic anhydride is selected from the group consisting of 4,4′

-oxybisphthalic anhydride;

3,3′

-oxybisphthalic anhydride; and

mixtures thereof.

6. The method according to claim 2, wherein the oxybisphthalic anhydride is selected from the group consisting of 4,4′

-oxybisphthalic anhydride;

3,4′

-oxybisphthalic anhydride; and

mixtures thereof.

7. The method according to claim 2, wherein the oxybisphthalic anhydride is selected from the group consisting of 3,4′

-oxybisphthalic anhydride;

3,3′

-oxybisphthalic anhydride; and

mixtures thereof.

8. The method according to claim 2, wherein said oxybisphthalic anhydride has structure (V)

9. The method according to claim 2, wherein said at least one solvent is selected from the group consisting of chlorobenzene, ortho-dichlorobenzene, para-dichlorobenzene, dichlorotoluene, 1,2,4-trichlorobenzene, diphenyl sulfone, phenetole, anisole, veratrole, toluene, xylene, mesitylene, and mixtures thereof.

10. The method according to claim 2, wherein said at least one solvent is ortho-dichlorobenzene.

11. The method according to claim 2, wherein said solid inorganic adsorbent material is selected from the group consisting of silica, alumina, zeolites, inorganic ion exchange compounds, and mixtures thereof.

12. The method according to claim 2, wherein said solid inorganic adsorbent material is silica.

13. The method according to claim 2, wherein said solid inorganic adsorbent material is alumina.

14. The method according to claim 2, wherein said solid inorganic adsorbent material has a cumulative pore volume distribution of about 20 percent or greater of particles having a pore diameter in a range between about 10 nanometers and about 20 nanometers.

15. The method according to claim 2, wherein said organic phase transfer catalyst is present in said first solution in an amount corresponding to between about 0.1 and 10 mole percent based on the amount of the oxybisphthalic anhydride initially present.

16. The method according to claim 2, wherein said organic phase transfer catalyst is present in said second solution in an amount corresponding to from about 2 parts per million to about 120 parts per million.

17. A method of preparing a polyetherimide, said method comprising reacting at least one aromatic diamine with a purified oxybisphthalic anhydride, said purified oxybisphthalic anhydride having structure (IV)

18. The method of claim 17, further comprising crystallizing the oxybisphthalic anhydride (IV) from the second solution to provide a purified oxybisphthalic anhydride containing less than about 150 ppm of said phase transfer catalyst.

19. A method of preparing a polyetherimide, said method comprising reacting at least one aromatic diamine with a purified oxybisphthalic anhydride, said purified oxybisphthalic anhydride having structure (IV)

20. The method of claim 19, further comprising crystallizing the oxybisphthalic anhydride IV from the second solution to provide a purified oxybisphthalic anhydride containing less than about 150 ppm of said organic phase transfer catalyst.