Charge Transporting Semi-Conducting Material and Semi-Conducting Device

A charge transporting semi-conducting material comprising:

• a cross-linked charge-transporting polymer comprising 1,2,3-triazole crosslinking units of the general formulae Ia and/or Ib,
• wherein
• aa) Pol1-Pol4 are independently selected charge-transporting polymers,
• bb) X1, X2, X3, and X4 are independently selected spacer units or represent direct bonding of Pol1-Pol4 to the 1,2,3-triazole ring, and
• cc) R and R′ are independently selected from the group consisting of
• H, halogen, nitrile, C1-C22 saturated or unsaturated alkyl, C3-C22 cycloalkyl, C6-C18 aryl, C7-C22 arylalkyl,
• C2-C13 heteroaryl having up to three heteroatoms independently selected from oxygen, nitrogen, and sulphur,
• SiR1R2R3, wherein R1, R2 and R3 are independently selected from C1-C4 alkyl or phenyl,
• COR4 or COOR5, wherein R4 and R5 are independently selected from C1-C22 alkyl or C7-C22 arylalkyl,
• CR6R7OR8, wherein R6 and R7 are independently selected from H, C1-C6 alkyl, C6-C9 aryl, or R6 and R7 together form a C3-C7 ring, and R8 is C1-C6 alkyl, C7-C22 arylalkyl, SiR9R10R11, wherein R9, R10, and R11 are independently selected from C1-C4 alkyl or phenyl, or COR12, wherein R12 is H or C1-C21 alkyl;
• the charge transporting semi-conducting material being obtainable by a process comprising
• i) providing a solution containing
• aaa) a first precursor charge transporting polymer comprising at least one covalently attached azide group;
• and/or a second precursor charge transporting polymer comprising at least one covalently attached acetylenic group and
• bbb) at least one solvent,
• ii) depositing the solution on a substrate,
• iii) removing the solvent, and
• iv) reacting the azide and acetylenic groups to effect crosslinking,
• wherein the average number of azide and/or acetylenic groups per molecule in each the first precursor charge transporting polymer, and the second precursor charge transporting polymer is greater than 2.