Meltblown fibers and webs produced from liquid crystal polymers

Abstract

This invention relates to a novel microfiber, to a nonwoven web comprising said microfiber, and to a method of preparing said web. The meltblown microfibers have a diameter of less than 150 micrometers. The microfibers are prepared by meltblowing a liquid crystal polymer such as a wholly aromatic polyester amide of p, p' biphenol, p-hydroxybenzoic acid and terephthalic acid or a wholly aromatic polyester amide of 2-hydroxynaphthoic acid, p-aminophenol and terephthalic acid.

That which is claimed is: 
     
       1. A nonwoven web formed of meltblown microfibers consisting essentially of a liquid crystalline polyester polymer which comprises a wholly aromatic polyester amide wherein the polyester moieties are derived from p, p' biphenol, p-hydroxybenzoic acid and terephthalic acid. 
     
     
       2. A nonwoven web according to claim 1 wherein said meltblown microfibers have a diameter of less than 150 micrometers. 
     
     
       3. A nonwoven web according to claim 1 wherein said meltblown microfibers have a diameter of less than 20 micrometers. 
     
     
       4. A nonwoven web according to claim 1 wherein said meltblown microfibers are in the annealed state. 
     
     
       5. A nonwoven web formed of meltblown microfibers consisting essentially of a liquid crystalline polyester polymer which comprises a wholly aromatic polyester amide of 2-hydroxynaphthoic acid, p-aminophenol and terephthalic acid. 
     
     
       6. A nonwoven web according to claim 1 including a multiplicity of discrete point bonds in which the fibers of the web are fused and bonded together. 
     
     
       7. Meltblown microfibers formed of a liquid crystalline polyester polymer which comprises a wholly aromatic polyester amide wherein the polyester moieties are derived from p, p' biphenol, p-hydroxybenzoic acid and terephthalic acid. 
     
     
       8. Meltblown microfibers according to claim 7 wherein said microfibers are of a diameter of less than 150 micrometers. 
     
     
       9. Meltblown microfibers according to claim 7 wherein said microfibers are of a diameter of less than 20 micrometers. 
     
     
       10. Meltblown microfibers according to claim 7 in which said microfibers are in the annealed state. 
     
     
       11. Meltblown microfibers formed of a liquid crystalline polyester polymer which comprises a wholly aromatic polyester amide of 2-hydroxynaphthoic acid, p-aminophenol and terephthalic acid. 
     
     
       12. A filter comprising the meltblown nonwoven web of claim 1. 
     
     
       13. A battery separator comprising the meltblown nonwoven web of claim 1. 
     
     
       14. A packing for glands or shafts comprising the meltblown nonwoven web of claim 1. 
     
     
       15. A high temperature laminate comprising the meltblown nonwoven web of claim 1 laminated to at least one other component layer. 
     
     
       16. A reinforced molded article comprising a molding resin having reinforcing fibers according to claim 7 dispersed therein. 
     
     
       17. A reinforced molded article according to claim 16 wherein the molding resin is a thermoplastic resin selected from the group consisting of polyesters, nylons, and acetals. 
     
     
       18. A reinforced molded article according to claim 16 wherein the molding resin is a thermosetting composition selected from the group consisting of epoxides, phenolics and amino-resins.