Semiconductor compounds
This invention comprises a semiconducting polymer having a permittivity greater than 3.4 at 1000 Hz and a charge mobility in the pure state greater than 10 −7 cm 2 V −1 s −1 and more preferably greater than 10 −6 cm 2 V −1 s −1 . Preferred polymers include repeating units of triarylamines which have specific cyano and/or alkoxy substitution. They are suitable for use in electronic components such as organic thin film transistors.
1. A semiconducting polymer having a permittivity greater than 3.4 at 1000 Hz and a charge mobility in the pure state of greater than 10 −7 cm 2 V −1 S −1 , wherein the semiconductingpolymer comprises substituted triarylamine repeat units, and wherein the substituted triarylamine repeat units comprise at least one of the following attributes:
(i) indirectly substituted by at least one cyano group, wherein the at least one cyano group is attached to an aromatic group of a substituted triarylamine by a linking group;
(ii) directly substituted by at least two alkoxy groups, wherein the at least two alkoxy groups are in the 2, 4 or 6 positions of a pendant aromatic ring; and
combinations thereof.
2. The semiconducting polymer according to claim 1 , wherein the triarylamine repeat units comprise at least one of the following structures:
3. The semiconducting polymer according to claim 1 , wherein the semiconducting polymer is represented by Formula (I) comprising first monomer units, second monomer units, and combinations thereof:
wherein each R x is independently selected from the group consisting of hydrogen, an alkyl group, an alkoxy group, halogen, a nitro group, R y , and combinations thereof;
wherein each R y is independently an organic group that includes at least one CN group, with the proviso that at least one repeat unit in the semiconducting polymer includes an R y group;
wherein the sum of indices (j+k+l) is at least one;
wherein each R z is independently an alkyl group optionally substituted by at least one substituent selected from the group consisting of hydroxyl, alkoxy, alkylsulphonyl, halogen, cyano, nitro, amino, carboxyl, and combinations thereof;
wherein each A is independently selected from the group consisting of hydrogen, halogen any suitable end-capping group, and combinations thereof;
wherein j and l are independently in each occurrence 0 to 4;
wherein k is independently in each occurrence 0 to 5;
wherein a is the number of first monomer units; and
wherein b is the number of second monomer units, which may be 0.
4. A semiconducting polymer according to claim 1 , wherein the semiconducting polymer is represented by Formula (I) comprising first monomer units, second monomer units, and combinations thereof:
wherein each R x is independently selected from the group consisting of hydrogen, an alkyl group, an alkoxy group, halogen, a nitro group, R y , and combinations thereof;
wherein each R y is independently selected from the group consisting of a cyano group (CN), an organic group that includes at least one CN group, and combinations thereof;
wherein the semiconducting polymer comprises at least two alkoxy substituents R x in the 2, 4 or 6 positions of a pendant aromatic ring;
wherein the sum of indices (j+k+l) is at least one;
wherein each R z is independently an alkyl group optionally substituted by at least one substituent selected from the group consisting of hydroxyl, alkoxy, alkylsulphonyl, halogen, cyano, nitro, amino, carboxyl, and combinations thereof;
wherein each A is independently selected from the group consisting of hydrogen, halogen, any suitable end-capping group, and combinations thereof;
wherein j and l are independently in each occurrence 0 to 4;
wherein k is independently in each occurrence 0 to 5;
wherein a is the number of first monomer units; and
wherein b is the number of second monomer units, which may be 0.
5. The semiconducting polymer according to claim 4 , wherein methoxy groups are substituted in the 2- and 4-positions on the pendant aromatic ring.
6. The semiconducting polymer according to claim 1 , wherein the semiconducting polymer is a copolymer represented by the following formula:
wherein a is the number of first monomer units,
wherein b is the number of second monomer units, and
wherein each A is independently selected from the group consisting of hydrogen, halogen, any suitable end-capping group, and combinations thereof.