Relaxed polyhydroxyalkanoate fiber and fabric and article comprising the same

Abstract

A method of making a relaxed polyhydroxyalkanoate fiber is disclosed. The method comprises subjecting a polyhydroxyalkanoate fiber comprising a polyhydroxyalkanoate to a temperature greater than or equal to a glass transition temperature of the polyhydroxyalkanoate and less than the melting temperature of the polyhydroxyalkanoate to form the relaxed polyhydroxyalkanoate fiber.

1 . A method of making a relaxed polyhydroxyalkanoate fiber, the method comprising:
 subjecting a polyhydroxyalkanoate fiber comprising a polyhydroxyalkanoate to a temperature greater than or equal to a glass transition temperature of the polyhydroxyalkanoate and less than the melting temperature of the polyhydroxyalkanoate to form the relaxed polyhydroxyalkanoate fiber.   
     
     
         2 . The method of  claim 1 , wherein the polyhydroxyalkanoate comprises a homopolymer. 
     
     
         3 . The method of  claim 1 , wherein the polyhydroxyalkanoate comprises a copolymer. 
     
     
         4 . The method of  claim 1 , wherein the polyhydroxyalkanoate has a monomeric unit of the following formula:
 —OCR 1 R 2 (CR 3 R 4 ) n CO—   
       wherein
 n is an integer; and 
 R 1 , R 2 , R 3 , and R 4  independently can be a hydrocarbon radical; a halo-and hydroxy-substituted radical; a hydroxy radical; a halogen radical; a nitrogen-substituted radical; an oxygen-substituted radical; or a hydrogen atom. 
 
     
     
         5 . The method of  claim 4 , wherein n is from 1 to 3. 
     
     
         6 . The method of  claim 4 , wherein R 1 , R 2 , R 3 , and R 4  independently can be hydrocarbon radicals or hydrogen atoms. 
     
     
         7 . The method of  claim 6 , wherein the hydrocarbon radical is an alkyl radical. 
     
     
         8 . The method of  claim 1 , wherein the polyhydroxyalkanoate comprises a 3-hydroxybutyrate monomeric unit. 
     
     
         9 . The method of  claim 1 , wherein the polyhydroxyalkanoate comprises poly-3-hydroxybutyrate-co-3-hydroxyhexanoate. 
     
     
         10 . The method of  claim 1 , wherein the polyhydroxyalkanoate fiber exhibits a shrinkage of from 1% or more to 80% or less to form the relaxed polyhydroxyalkanoate fiber. 
     
     
         11 . The method of  claim 1 , wherein the polyhydroxyalkanoate fiber exhibits a shrinkage of from 10% or more to 70% or less to form the relaxed polyhydroxyalkanoate fiber. 
     
     
         12 . The method of  claim 1 , wherein the polyhydroxyalkanoate fiber exhibits a shrinkage of from 30% or more to 70% or less to form the relaxed polyhydroxyalkanoate fiber. 
     
     
         13 . A relaxed polyhydroxyalkanoate fiber made according to the method of  claim 1 . 
     
     
         14 . A fabric comprising the relaxed polyhydroxyalkanoate fiber of  claim 13 . 
     
     
         15 . The fabric of  claim 14 , wherein the fabric is a knit fabric. 
     
     
         16 . The fabric of  claim 14 , wherein the fabric is a woven fabric.