Electronic device, method, monomer and polymer

Abstract

The electronic device of the invention comprises one or more active elements, each comprising a first and a second electrode and an active layer of organic material separating the first and second electrodes. Examples of active elements are thin-film transistors and light-emitting diodes. The active layer comprises a polymeric material having conjugated units A and non-conjugated intermediate units B, which intermediate units B separate the conjugated units A from each other, such that no conjugation extends from a first conjugated unit A 1 to a second conjugated unit A 2 . The polymeric material may be a polymer network, an alternating copolymer or a polymer in which the conjugated units are present in side chains. The polymer can be prepared from monomers having a B 1 -A 1 -B 2 structure, wherein at least one of B 1 and B 2 comprises a reactive group enabling polymerization.

1 . An electronic device provided with an active element having a first and a second electrode, which are separated from each other by an active layer containing a semiconductive or electroluminescent organic material, characterized in that the organic material of an active layer is a polymer comprising conjugated conjugation units which are separated from each other by non-conjugated intermediate units B in such a manner that the conjugation of the first and the second conjugation unit A 1 , A 2  is interrupted in an intermediate unit B 1 .  
     
     
         2 . An electronic device as claimed in  claim 1 , characterized in that the polymer is polymer network comprising a first and a second main chain which are interconnected via side chains, a side chain containing a B 1 -A 1 -B 2  structure, with B 1 , B 2  being intermediate units and Al being a conjugation unit.  
     
     
         3 . An electronic device as claimed in  claim 1 , characterized in that the polymer is a copolymer comprising a main chain, the intermediate units B and the conjugation units A being present in the main chain as alternating units . . . -A 1 -B 1 -A 2 -B 2 - . . . .  
     
     
         4 . An electronic device as claimed in  claim 1 , characterized in that the polymer comprises a main chain with side chains, a side chain containing a B 1 -A 1 -B 2 - structure, wherein B 1 , B 2  are intermediate units and Al is a conjugation unit.  
     
     
         5 . An electronic device as claimed in  claim 1 , characterized in that the intermediate unit B 1  comprises a mesogenic group.  
     
     
         6 . An electronic device as claimed in any one of the preceding claims, characterized in that the conjugation unit is a unit of formula Y n , wherein 2≦n≦8 and Y is selected from the group composed of  
       
         
           
           
               
               
           
         
       
       wherein 
 Ar is an aromatic ring system with 4 to 6 carbon atoms that may be substituted with a substituent selected from the group composed of an unbranched C 1 -C 20 -alkyl-, C 3 -C 20 -alkoxy-, C 1 -C 20 -alkylsulphate-, a branched C 3 -C 20 -alkyl-, phenyl or benzyl group, and that may comprise up to 4 heteroatoms selected from the group composed of oxygen, sulfur and nitrogen in the aromatic ring system, and  
 R 2  and R″ 2  are selected from the group composed of a hydrogen atom and a C 1 -C 20 alkyl- and a C 4 -C 20 -aryl group, which groups may comprise substituents.  
 
     
     
         7 . An electronic device as claimed in  claim 1 , characterized in that a second active element is present, which contains a first and a second electrode which are mutually separated by the active layer, and in that the active layer has a relief structure, so that the active layer between the first and the second active element is removed.  
     
     
         8 . An electronic device as claimed in  claim 1  or 7, characterized in that the active element is a transistor wherein a third electrode is present which is separated from the active layer by a dielectric, and wherein the active layer comprises an intrinsic, undoped semiconductive material.  
     
     
         9 . A method of preparing a polymer comprising conjugated conjugation units A and non-conjugated intermediate units B, an intermediate unit B 1  mutually separating a first and a second conjugation unit A 1 , A 2  in such a manner that the conjugation of the first and the second conjugation unit A 1 , A 2  is interrupted in the intermediate unit B 1 , characterized in that the polymer is prepared from a monomer having a B 1 -A 1 -B 2  structure, wherein at least one of the groups B 1 , B 2  comprises a reactive end group.  
     
     
         10 . A monomer having a B 1 -A 1 -B 2  structure, wherein A 1  is a conjugated unit of formula Y n , wherein 2≦n≦8 and Y is selected from the group composed of  
       
         
           
           
               
               
           
         
       
       wherein 
 Ar is an aromatic ring system with 4 to 6 carbon atoms that may be substituted with a substituent selected from the group composed of an unbranched C 1 -C 20 -alkyl-, C 3 -C 20 -alkoxy-, C 1 -C 20 -alkyl sulphate-, a branched C 3 -C 20 -alkyl-, phenyl- or benzyl group, and that may contain up to 4 heteroatoms selected from the group composed of oxygen, sulfur and nitrogen in the aromatic ring system, and  
 R 2  and R″ 2  are selected from the group composed of a hydrogen atom and a C 1 -C 20 -alkyl- and a C 4 -C 20 -aryl group, which groups may comprise substituents,  
 and wherein B 1 , B 2  are non-conjugated groups.  
 
     
     
         11 . A method as claimed in  claim 9 , characterized in that the monomer used is the monomer as claimed in  claim 10 .  
     
     
         12 . A polymer that can be obtained by means of the method as claimed in  claim 9.