IP Library Granted Patent US 7,803,247
Granted Patent B2
US 7,803,247 · App. 12/004,901 · Granted Sep 28, 2010

Papers containing floc derived from diamino diphenyl sulfone

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Quick Facts
Patent No.
US 7,803,247
App. No.
12/004,901
Granted
Sep 28, 2010
Kind
B2
Abstract

This invention relates to papers made with floc containing a polymer or copolymer derived from a monomer selected from the group consisting of 4,4′diaminodiphenyl sulfone, 3,3′diaminodiphenyl sulfone, and mixtures thereof. Such papers have higher elongation-at-break and work-to-break (toughness) properties and exhibit less shrinkage at high temperatures than papers made with solely with poly (metaphenylene isophthalamide) floc.

Claims (15)

1. A paper useful for electrical insulation, comprising:

a) at least 20 weight percent floc containing a polymer or copolymer derived from an amine monomer selected from the group consisting of 4,4′diaminodiphenyl sulfone, 3,3′diaminodiphenyl sulfone, and mixtures thereof, the floc having a length of from 2 to 25 mm; and

b) non-granular, fibrous or film-like polymer fibrids, the fibrids containing a polymer or copolymer derived from metaphenylene diamine, the fibrids having an average maximum dimension of 0.1 to 1 mm, a ratio of maximum to minimum dimension of 5:1 to 10:1, and a thickness of no more than 2 microns,

wherein the papers have at least a 50% improvement in work-to-break values over papers made solely with poly(metaphenylene isophthalamide) floc.

2. The paper of claim 1 wherein weight ratio of fibrids to floc in the paper is from 95:5 to 3:97.

3. The paper of claim 2 wherein the weight ratio of fibrids to floc in the paper is from 60:40 to 10:90.

4. The paper of claim 1 , wherein fibrids are made from poly(metaphenylene isophthalamide).

5. The paper of claim 4 wherein the poly(metaphenylene isophthalamide) fibrids are 50 to 80 weight percent of the total amount of fibrids in the paper.

6. The paper of claim 1 , further comprising fibrids comprising polymer or copolymer derived from an amine monomer selected from the group consisting of 4,4′diaminodiphenyl sulfone, 3,3′diaminodiphenyl sulfone, and mixtures thereof.

7. The paper of claim 6 wherein the total amount of fibrids in the paper comprise 80 to 20 weight percent fibrids made from a polymer or copolymer derived from an amine monomer selected from the group consisting of 4,4′diaminodiphenyl sulfone, 3,3′diaminodiphenyl sulfone, and mixtures.

8. The paper of claim 1 , further comprising:

c) floc selected from the group of para-aramid, meta-aramid, carbon, glass, polyethylene terephthalate, polyethylene napthalate, liquid crystalline polyesters, polyphenylene sulfide, polyether-ketone-ketone, polyether-ether-ketone, polyoxadiazole, polybenzazole, and mixtures thereof, the floc having a length of from 2 to 25 mm.

9. A wire or conductor wrapped with the paper of claim 1 .

10. A laminate structure or electrical device comprising the paper of claim 1 .

11. A honeycomb structure comprising the paper of claim 1 .

Assignments (2)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Jun 25, 2019
From: E. I. DU PONT DE NEMOURS AND COMPANY
To: DUPONT SAFETY & CONSTRUCTION, INC.
Reel/Frame 051180/0648 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Apr 28, 2008
From: LEVIT, MIKHAIL R.; HENDREN, GARY LEE; GABARA, VLODEK
To: E. I. DU PONT DE NEMOURS AND COMPANY
Reel/Frame 020864/0100 →