Filament or Fibre

Abstract

A filament or fibre comprising a liquid crystalline elastomer, and an actuator for enabling actuation of the filament or fibre to thereby cause a change in the dimensions of the filament or fibre.

1 . A filament or fibre ( 10 ) comprising a liquid crystalline elastomer ( 2 ), and an actuator ( 14 ) for enabling actuation of the filament or fibre to thereby cause a change in the dimensions of the filament or fibre.  
   
   
       2 . A filament or fibre according to  claim 1  wherein the liquid crystalline elastomer comprises a functional long chain elastomer ( 4 ), a plurality of mesogenic side chains ( 6 ), and a cross linker ( 8 ).  
   
   
       3 . A filament or fibre according to  claim 2  wherein at least some of the mesogenic side chains are aligned.  
   
   
       4 . A filament or fibre according to  claim 1  wherein the actuator comprises an electrode ( 14 ) extending axially along the fibre or filament.  
   
   
       5 . A filament or fibre according to  claim 4  in which the electrode ( 16 ) is elastic.  
   
   
       6 . A filament or fibre according to  claim 5  in which the electrode ( 14 ) is corrugated.  
   
   
       7 . A filament or fibre according to  claim 1  wherein the electrode comprises a spiralled wire ( 22 ) extending at least partially along the length of the fibre or filament.  
   
   
       8 . A filament or fibre according to  claim 4  in which the electrode is a Cr—Au electrode.  
   
   
       9 . A filament or fibre according to  claim 4  in which the electrode extends substantially along an outer surface of the fibre or filament.  
   
   
       10 . A filament or fibre according to  claim 4  in which the electrode extends within the fibre or filament.  
   
   
       11 . A filament or fibre according to  claim 1  wherein the actuator comprises first ( 30 ) and second ( 30 ) electrodes, each of which are separate from one another.  
   
   
       12 . A filament or fibre according to  claim 11  wherein each of the first and second electrodes extends substantially along an outer surface of the filament or fibre.  
   
   
       13 . A filament or fibre according to  claim 11  wherein the first electrode extends substantially along an outer surface of the filament or fibre, and the second electrode extends within the filament or fibre.  
   
   
       14 . A filament or fibre according to  claim 11  wherein the first and second electrode each comprise finger electrodes ( 32 ,  34 ).  
   
   
       15 . A filament or fibre according to  claim 1  wherein the actuator comprises a conducting species.  
   
   
       16 . A filament or fibre according to  claim 15  in which the conducting species comprises carbon fibres.  
   
   
       17 . A filament or fibre according to  claim 15  in which the conducing species comprises conducting polymers.  
   
   
       18 . A filament or fibre according to  claim 1  wherein the liquid crystalline elastomer comprises a ferro-electric liquid crystalline elastomer.  
   
   
       19 . A filament or fibre according to  claim 2  dependent thereon wherein the actuator comprises azo groups incorporated into the mesogenic side chains.  
   
   
       20 . A fabric ( 42 ) comprising a plurality of elastomer fibres formed form a liquid crystalline elastomer, and a plurality of conductive wires interwoven with the elastomer fibres.  
   
   
       21 . A fabric formed from a plurality of filaments or fibres according to  claim 1 .  
   
   
       22 . A garment formed from fabric according to  claim 20 .  
   
   
       23 . A blood pressure measuring device formed from a fabric according to  20 .  
   
   
       24 . A device for controlling thermal insulation formed from a fabric according to  claim 20.