PHOSPHONATED PBI FIBER

• US 20170009383A1
• Filed: 06/27/2016
• Published: 01/12/2017
• Est. Priority Date: 07/06/2015
• Status: Active Grant

• Current Assignee: Pbi Performance Products Incorporated (Intertech Group Incorporated)
• Original Assignee: Pbi Performance Products Incorporated (Intertech Group Incorporated)
• Inventors: Shiels, Brian P., Copeland, Gregory S., Qin, Feng
• Granted Patent: US 11,959,196 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: C08G 73/18 Polybenzimidazoles
• CPC Class Codes: D01F 1/07 for making fire- or flame-proof filaments
• CPC Class Codes: D01F 6/74 from polycondensates of cyclic compounds, e.g. polyimides, polybenzimidazoles
• CPC Class Codes: D06M 11/70 with oxides of phosphorus; with hypophosphorous, phosphorous or phosphoric acids or their salts
• CPC Class Codes: D06M 11/84 combined with mechanical treatment combined with mechanical tension, e.g. mercerising D06M11/40
• CPC Class Codes: D06M 2200/30 Flame or heat resistance, fire retardancy properties

Abstract

A fiber is made with a polybenzimidazole (PBI) polymer with a phosphoric acid pick-up (APU) in the range of 1-25% (PBI-p fiber). The PBI-p fiber may have a LOI≧50% and/or an initial thermal decomposition temperature in air of 555° C. A method of making a phosphonated polybenzimidazole fiber comprises the steps of: spinning an untreated PBI resin into a PBI fiber; treating the PBI fiber with phosphoric acid, and thereby obtaining a PBI fiber with 1-25 wt. % phosphoric acid APU.

Claims

1. A fiber comprises a polybenzimidazole (PBI) polymer with a phosphoric acid pick-up (APU) in the range of 1-25%.

2. The fiber of claim 1 wherein the phosphoric acid APU is in the range of 4-20%.

3. The fiber of claim 1 wherein the phosphoric acid APU is in the range of 12-20%.

4. The fiber of claim 1 wherein the phosphoric acid APU is in the range of 8-24%.

5. The fiber of claim 1 wherein the phosphoric acid APU is 17%.

6. The fiber of claim 1 wherein the LOI (Limiting Oxygen Index) is about 47%.

7. The fiber of claim 1 wherein the initial thermal decomposition temperature in air is about ≧

555°

C.

8. The fiber of claim 1 having a denier no greater than 6 dpf.

9. The fiber of claim 1 is a staple or a filament.

10. A yarn comprises the fiber of claim 1.

11. A fabric comprises the yarn of claim 10.

12. The fabric of claim 11 is a woven fabric or a knitted fabric.

13. A garment comprises the fabric of claim 11.

14. A nonwoven comprises the fiber of claim 1.

15. A method of making a phosphonated polybenzimidazole fiber comprises the steps of:

spinning an untreated PBI resin into a PBI fiber;

treating the PBI fiber with phosphoric acid, and

thereby obtaining a PBI fiber with 1-25 wt. % phosphoric acid.

16. The method of claim 15 wherein the phosphoric acid is a 10-85 wt. % phosphoric acid (aqueous).

17. The method of claim 15 wherein the phosphoric acid is a 40-60 wt. % phosphoric acid (aqueous).

18. The method of claim 15 wherein the phosphoric acid is a 50 wt. % phosphoric acid (aqueous).

19. The method of claim 15 wherein the treating is conducted at a temperature in the range of 15-50°

C.

20. The method of claim 15 further comprising tensioning the fiber during applying the acid.