Multicomponent fibers comprising starch and biodegradable polymers

Abstract

The present invention discloses environmentally degradable multicomponent fibers. The configuration of the multicomponent fibers may be side-by-side, sheath-core, segmented pie, islands-in-the-sea, or any combination of configurations. Each component of the fiber will comprise destructurized starch and/or a biodegradable thermoplastic polymer. The present invention is also directed to nonwoven webs and disposable articles comprising the environmentally degradable multicomponent fibers. The nonwoven webs may also contain other synthetic or natural fibers blended with the multicomponent fibers of the present invention.

1 . An environmentally degradable multicomponent fiber having a diameter of less than 100 micrometers and having a configuration selected from the group consisting of sheath-core, islands-in-the-sea, ribbon, segmented pie, side-by-side, and combination thereof; wherein each component of the environmentally degradable multicomponent fiber comprises a material selected from group consisting of:
 a. destructurized starch having a molecular weight in the range from 3000 g/mol to 1,000,000 g/mol;   b. biodegradable thermoplastic polymer having a molecular weight of less than 500,000 g/mol and selected from the group consisting of aliphatic polyesteramides; diacids/diols aliphatic polyesters; modified aromatic polyesters; aliphatic/aromatic copolyesters; polycaprolactones; poly(hydroxyalkanoates); polyesters and polyurethanes derived from aliphatic polyols; polyamides; polyethylene/vinyl alcohol copolymers; glycolide polymers; and combinations thereof; and   c. combinations thereof; and   at least one component of the multicomponent fiber has a different material composition than one other component.   
     
     
         2 . The environmentally degradable multicomponent fiber of  claim 1  wherein one component comprises:
 a. destructurized starch having a molecular weight in the range from 3000 g/mol to 1,000,000 g/mol, 
 b. a biodegradable thermoplastic polymer; and 
 c. a plasticizer. 
 
     
     
         3 . The environmentally degradable multicomponent fiber of  claim 1  wherein one component comprises destructurized starch and a second component comprises a biodegradable thermoplastic polymer. 
     
     
         4 . The environmentally degradable multicomponent fiber of  claim 1  wherein the fiber has a diameter of less than 50 micrometers. 
     
     
         5 . The environmentally degradable multicomponent fiber of  claim 1  wherein the fiber is splittable. 
     
     
         6 . The environmentally degradable multicomponent fiber of  claim 1  wherein the fiber is thermally bondable. 
     
     
         7 . A nonwoven web comprising the environmentally degradable multicomponent fibers of  claim 6 . 
     
     
         8 . A nonwoven web wherein the environmentally degradable multicomponent fibers of  claim 6  are blended with other synthetic or natural fibers and bonded together. 
     
     
         9 . A disposable article comprising the nonwoven web of  claim 8 . 
     
     
         10 . A nonwoven web comprising environmentally degradable multicomponent fibers having a diameter of less than 100 micrometers and having a configuration selected from the group consisting of sheath-core, islands-in-the-sea, ribbon, segmented pie, side-by-side, and combination thereof; wherein each component of the environmentally degradable multicomponent fiber comprises a material selected from group consisting of:
 a. destructurized starch having a molecular weight in the range from 3000 g/mol to 1,000,000 g/mol;   b. biodegradable thermoplastic polymer having a molecular weight of less than 500,000 g/mol and selected from the group consisting of aliphatic polyesteramides; diacids/diols aliphatic polyesters; modified aromatic polyesters; aliphatic/aromatic copolyesters; polycaprolactones; poly(hydroxyalkanoates); polyesters and polyurethanes derived from aliphatic polyols; polyamides; polyethylene/vinyl alcohol copolymers; glycolide polymers; and combinations thereof; and   c. combinations thereof; and   at least one component of the multicomponent fiber has a different material composition than one other component.   
     
     
         11 . A nonwoven web wherein the environmentally degradable multicomponent fibers of  claim 10  are blended with other synthetic or natural fibers and bonded together. 
     
     
         12 . A disposable article comprising the nonwoven web of  claim 10 . 
     
     
         14 . An environmentally degradable bicomponent fiber having a diameter of less than 100 micrometers and having a sheath-core configuration wherein the sheath comprises a biodegradable thermoplastic polymer having a molecular weight of less than 500,000 g/mol and selected from the group consisting of aliphatic polyesteramides; diacids/diols aliphatic polyesters; modified aromatic polyesters; aliphatic/aromatic copolyesters; polycaprolactones; poly(hydroxyalkanoates); polyesters and polyurethanes derived from aliphatic polyols; polyamides; polyethylene/vinyl alcohol copolymers; glycolide polymers; and combinations thereof; and combinations thereof; and the core comprises destructurized starch having a molecular weight in the range from 3000 g/mol to 1,000,000 g/mol.