Functional cashmere fiber and fabrication method thereof

Abstract

A functional cashmere fiber includes a cashmere fiber, a boron-doped TiO 2 layer and a carboxymethyl cellulose (CMC) binder. The CMC binder binds the boron-doped TiO 2 layer on the cashmere fiber such that the boron-doped TiO 2 layer at least partially covers the cashmere fiber. The functional cashmere fiber provides self-cleaning function under visible light and high washing stability.

1 . A functional cashmere fiber comprising:
 a cashmere fiber;   a layer comprising boron-doped titanium dioxide (TiO 2 ); and   a binder comprising carboxymethyl cellulose (CMC) for binding the layer on the cashmere fiber such that the layer at least partially covers the cashmere fiber.   
     
     
         2 . The functional cashmere fiber of  claim 1 , wherein the boron-doped TiO 2  has a molar ratio of boron to titanium between 0.3:1 and 1.2:1. 
     
     
         3 . The functional cashmere fiber of  claim 1 , wherein the layer has a thickness between 10 nm and 100 nm. 
     
     
         4 . The functional cashmere fiber of  claim 1 , wherein the layer fully covers the cashmere fiber. 
     
     
         5 . The functional cashmere fiber of  claim 1 , wherein the cashmere fiber has a diameter between 5 μm and 30 μM. 
     
     
         6 . The functional cashmere fiber of  claim 1 , wherein the boron-doped TiO 2  has a molar ratio of boron to titanium between 0.9:1 and 1.1:1, and the layer has a thickness between 10 nm and 50 nm. 
     
     
         7 . A functional yarn comprising the functional cashmere fiber of  claim 1 . 
     
     
         8 . A functional fabric comprising the functional cashmere fiber of  claim 1 . 
     
     
         9 . A method for fabricating the functional cashmere fiber of  claim 1  comprising:
 providing a CMC-coated fiber, wherein the CMC-coated fiber is a cashmere fiber coated with CMC; and 
 contacting the CMC-coated fiber with boron-doped TiO 2  thereby forming the functional cashmere fiber. 
 
     
     
         10 . The method of  claim 9 , wherein the boron-doped TiO 2  has a molar ratio of boron to titanium between 0.3:1 and 1.2:1. 
     
     
         11 . The method of  claim 9  further comprising:
 contacting the cashmere fiber with a first solution comprising CMC thereby forming the CMC-coated fiber. 
 
     
     
         12 . The method of  claim 11 , wherein the first solution is a CMC sodium salt solution. 
     
     
         13 . The method of  claim 11 , wherein the first solution has a CMC concentration between 0.1% (v/v) and 1% (v/v). 
     
     
         14 . The method of  claim 9 , wherein the step of contacting the CMC-coated fiber with boron-doped TiO 2  comprises:
 contacting the CMC-coated fiber with a second solution comprising boron-doped TiO 2  or a boron-doped TiO 2  precursor thereby forming a boron-doped TiO 2 -CMC-coated fiber; and   curing the boron-doped TiO 2 -CMC-coated fiber thereby forming the functional cashmere fiber.   
     
     
         15 . The method of  claim 14 , wherein the boron-doped TiO 2  precursor comprises a TiO 2  precursor, a boron precursor and an acidic aqueous solution. 
     
     
         16 . The method of  claim 15 , wherein the TiO 2  precursor is a titanium alkoxide or titanium tetrachloride, the boron precursor is a trialkyl borate or boric acid, the acidic aqueous solution is acetic acid, nitric acid or hydrochloric acid. 
     
     
         17 . The method of  claim 14 , wherein the step of curing comprises curing the boron-doped TiO 2 -CMC-coated fiber at a temperature between 90° C. and 150° C. 
     
     
         18 . The method of  claim 9 , wherein the method for fabricating the functional cashmere fiber comprises:
 contacting a cashmere fiber with a first solution comprising CMC thereby forming the CMC-coated fiber, wherein the first solution is a CMC sodium salt solution having a CMC concentration between 0.4% (v/v) and 0.6% (v/v);   contacting the CMC-coated fiber with a second solution comprising the boron-doped TiO 2  or a boron-doped TiO 2  precursor thereby forming a boron-doped TiO 2 -CMC-coated fiber, wherein the boron-doped TiO 2  has a molar ratio of boron to titanium between 0.9:1 and 1.1:1; and   curing the boron-doped TiO 2 -CMC-coated fiber at a temperature between 110° C. and 130° C. thereby forming the functional cashmere fiber.   
     
     
         19 . A method for fabricating a functional cashmere yarn comprising:
 providing a CMC-coated yarn, wherein the CMC-coated yarn is a cashmere yarn coated with CMC;   contacting the CMC-coated yarn with a second solution comprising the boron-doped TiO 2  or a boron-doped TiO 2  precursor thereby forming a boron-doped TiO 2 -CMC-coated yarn; and   curing the boron-doped TiO 2 -CMC-coated yarn thereby forming the functional cashmere yarn.   
     
     
         20 . A method for fabricating a functional cashmere fabric comprising:
 providing a CMC-coated fabric, wherein the CMC-coated fabric is a cashmere fabric coated with CMC;   contacting the CMC-coated fabric with a second solution comprising the boron-doped TiO 2  or a boron-doped TiO 2  precursor thereby forming a boron-doped TiO 2 -CMC-coated fabric; and   curing the boron-doped TiO 2 -CMC-coated fabric thereby forming the functional cashmere fabric.