Fibers comprising copolymers containing structures derived from 4,4 diamino diphenyl sulfone and a plurality of acid monomers and methods of making same
View Patent ↗The invention concerns a fiber, obtainable by spinning a copolymer from the polymerization solution, derived from 4,4′diaminodiphenyl sulfone amine monomer and a plurality of acid monomers, wherein the plurality of acid monomers has 55 to 85 mole percent of the monomer containing a para-oriented aromatic group and 15 to 45 mole percent of the monomer containing a meta-oriented aromatic group; and yarns, fabrics and garments comprising this fiber, and methods of making the same. This fiber has use in heat-resistant protective apparel fabrics and garments.
1. A staple fiber having a macroscopically homogeneous body comprising a copolymer having a structure derived from the reaction of an amine monomer and a plurality of acid monomers, wherein
i) the amine monomer is at least 80 mole percent 4,4′diaminodiphenyl sulfone; and
ii) the plurality of acid monomers include those having a structure of
Cl—CO—Ar 1 —CO—Cl & Cl—CO—Ar 2 —CO—Cl
wherein the plurality of acid monomers has 55 to 85 mole percent of the monomer containing aromatic group Ar 1 and 15 to 45 mole percent of the monomer containing the aromatic group Ar 2 ; and
wherein the aromatic group Ar 1 is aromatic group having para-oriented linkages and the aromatic group Ar 2 is a an aromatic group having meta-oriented linkages.
2. The staple fiber of claim 1 wherein the plurality of acid monomers includes terephthaloyl chloride, isophthaloyl chloride and mixtures thereof.
3. A flame-resistant yarn comprising the staple fiber of claim 1 having a limiting oxygen index of 21 or greater.
4. The flame-resistant yarn of claim 3 having a limiting oxygen index of 26 or greater.
5. A flame-resistant yarn comprising the fiber of claim 1 wherein the yarn has a tenacity of 3 grams per denier (2.7 grams per dtex) or greater.
6. The flame-resistant yarn of claim 5 wherein the yarn has a tenacity of 4 grams per denier (3.6 grams per dtex) or greater.
7. A fabric comprising the staple fiber of claim 1 .
8. A protective garment comprising the staple fiber of claim 1 .