Alternating copolymers of phenylene vinylene and biarylene vinylene, preparation method thereof, and organic thin flim transister comprising the same

Abstract

Disclosed herein are an alternating copolymer of phenylene vinylene and biarylene vinylene, a preparation method thereof, and an organic thin film transistor including the same. The organic thin film transistor maintains low off-state leakage current and realizes a high on/off current ratio and high charge mobility because the organic active layer thereof is formed of an alternating copolymer of phenylene vinylene and biarylene vinylene.

1 . An alternating copolymer of phenylene vinylene and biarylene vinylene, represented by Formula 1 below: 
     
       
         
         
             
             
         
       
       wherein R 1 , R 2 , R 3 , and R 4  are each independently selected from a group consisting of hydrogen, a hydroxyl group, a C 1˜20  linear, branched or cyclic alkyl group, a C 1˜20  alkoxyalkyl group, and a C 1˜16  linear, branched or cyclic alkoxy group, 
       X is selected from a group consisting of S, O, NH, N-methyl, and Se, and 
       n is an integer from 4 to 200. 
     
   
   
       2 . The alternating copolymer of  claim 1 , wherein the alternating copolymer of phenylene vinylene and biarylene vinylene comprises a compound selected from a compound group represented by Formula 2 below: 
     
       
         
         
             
             
         
       
       wherein R 1  and R 2  are each independently selected from a group consisting of a hexyl group, a heptyl group, and an octyl group, 
       R 3  is selected from a group consisting of a butyl group, a hexyl group, and an octyl group, and 
       n is an integer from 4 to 200. 
     
   
   
       3 . The alternating copolymer of  claim 1 , wherein the alternating copolymer of phenylene vinylene and biarylene vinylene comprises a compound selected from a compound group represented by Formula 3 below: 
     
       
         
         
             
             
         
       
       
         
         
             
             
         
       
     
   
   
       4 . A method of preparing an alternating copolymer of phenylene vinylene and biarylene vinylene, comprising copolymerizing a monomer represented by Formula 4 below with a monomer represented by Formula 5 below: 
     
       
         
         
             
             
         
       
       wherein R 1  and R 2  are each independently selected from a group consisting of hydrogen, a hydroxyl group, a C 1˜20  linear, branched or cyclic alkyl group, a C 1˜20  alkoxyalkyl group, and a C 1˜16  linear, branched or cyclic alkoxy group, and 
       Y is a C 1˜4  alkyl group; and 
     
     
       
         
         
             
             
         
       
       wherein R 3  and R 4  are each independently selected from a group consisting of hydrogen, a hydroxyl group, a C 1˜20  linear, branched or cyclic alkyl group, a C 1˜20  alkoxyalkyl group, and a C 1˜16  linear, branched or cyclic alkoxy group, and 
       X is selected from a group consisting of S, O, NH, N-methyl, and Se. 
     
   
   
       5 . The method of  claim 4 , wherein the monomer represented by Formula 5 comprises a monomer selected from a monomer group represented by Formula 6 below: 
     
       
         
         
             
             
         
       
       wherein R 3  and R 4  are each independently selected from a group consisting of hydrogen, a hydroxyl group, a C 1˜20  linear, branched or cyclic alkyl group, a C 1˜20  alkoxyalkyl group, and a C 1˜16  linear, branched or cyclic alkoxy group. 
     
   
   
       6 . The method of  claim 4 , wherein the monomer represented by Formula 5 comprises a monomer selected from a monomer group represented by Formula 7 below: 
     
       
         
         
             
             
         
       
     
   
   
       7 . An organic thin film transistor, comprising a substrate, a gate electrode, a gate insulating layer, an organic active layer, and source/drain electrodes, in which the organic active layer is formed of an alternating copolymer of phenylene vinylene and biarylene vinylene, represented by Formula 1 below: 
     
       
         
         
             
             
         
       
       wherein R 1 , R 2 , R 3 , and R 4  are each independently selected from a group consisting of hydrogen, a hydroxyl group, a C 1˜20  linear, branched or cyclic alkyl group, a C 1˜20  alkoxyalkyl group, and a C 1˜16  linear, branched or cyclic alkoxy group, 
       X is selected from a group consisting of S, O, NH, N-methyl, and Se, and 
       n is an integer from 4 to 200. 
     
   
   
       8 . The organic thin film transistor of  claim 7 , wherein the alternating copolymer of phenylene vinylene and biarylene vinylene comprises a compound selected from a compound group represented by Formula 2 below: 
     
       
         
         
             
             
         
       
       wherein R 1  and R 2  are each independently selected from a group consisting of a hexyl group, a heptyl group, and an octyl group, 
       R 3  is selected from a group consisting of a butyl group, a hexyl group, and an octyl group, and 
       n is an integer from 4 to 200. 
     
   
   
       9 . The organic thin film transistor of  claim 7 , wherein the alternating copolymer of phenylene vinylene and biarylene vinylene comprises a compound selected from a compound group represented by Formula 3 below: 
     
       
         
         
             
             
         
       
       
         
         
             
             
         
       
     
   
   
       10 . An electronic device, comprising the alternating copolymer of phenylene vinylene and biarylene vinylene of any one of  claims 1  to  3 . 
   
   
       11 . The electronic device of  claim 10 , which is an organic light emitting device (OLED), an organic photovoltaic device, or a sensor.