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US-12628546-B2 - Polymer and organic light-emitting diode using same

US12628546B2US 12628546 B2US12628546 B2US 12628546B2US-12628546-B2

Abstract

The present specification relates to a polymer and an organic light emitting device using the same, wherein the polymer is represented by the following Chemical Formula 1: E1-[A] a —[B] b —[C] c -E2  [Chemical Formula 1] Wherein A, B, C, E1, E2, a, b and c are described herein.

Inventors

  • Ji Hoon Kim
  • Jaesoon Bae
  • Jaechol LEE
  • Juhwan Kim
  • Dongyoon Khim
  • Min Suk Jung

Assignees

  • LG CHEM, LTD.

Dates

Publication Date
20260512
Application Date
20210112
Priority Date
20200113

Claims (15)

  1. 1 . A polymer represented by Chemical Formula 1: E1-[A] a —[B] b —[C] c -E2 [Chemical Formula 1] in Chemical Formula 1, A is represented by Chemical Formula 2-1, B is represented by Chemical Formula 3, C is a substituted or unsubstituted arylene group; a substituted or unsubstituted divalent heterocyclic group; R37 to R39 are the same as or different from each other, and are each independently deuterium; a substituted or unsubstituted alkyl group; a substituted or unsubstituted aryl group; or a cross-linkable group, k4 is an integer from 0 to 4, k5 is an integer from 0 to 3, when k4 and k5 are each 2 or higher, each occurrence of R37 to R39 is the same as or different from each other, respectively, and * is a part that bonds to at least one of E1, A, B, C, or E2, E1 and E2 are the same as or different from each other, and are each independently hydrogen; deuterium; a substituted or unsubstituted alkyl group; a substituted or unsubstituted silyl group; a substituted or unsubstituted aryl group; a substituted or unsubstituted arylamine group; a substituted or unsubstituted siloxane group; a cross-linkable group; or a combination thereof, a, b, and c are each a mole fraction, a is a real number of 0<a≤1, b is a real number of 0<b<1, c is a real number of 0≤c<1, and a+b+c=1, in Chemical Formula 2-1, Ar2 and Ar3 are the same as or different from each other, and are each independently an aryl group unsubstituted or substituted with an alkyl group, Ar1 and Ar4 are the same as or different from each other, and are each independently an arylene group, R1 and R2 are each a F, R3 is a hexyl group, n3 is 2, and * is a part that bonds to at least one of E1, A, B, C, or E2, in Chemical Formula 3, m is an integer of 3 or 4, when m is 3, Z is CRa; SiRa; N; or a substituted or unsubstituted trivalent aryl group, when m is 4, Z is C; Si; or a substituted or unsubstituted tetravalent aryl group, Ra is hydrogen; a substituted or unsubstituted alkyl group; or a substituted or unsubstituted aryl group, Y is a direct bond; a substituted or unsubstituted alkylene group; or a substituted or unsubstituted arylene group, when Y is a direct bond; or a substituted or unsubstituted alkylene group, Z is a substituted or unsubstituted trivalent or tetravalent aryl group, and * is a part that bonds to at least one of E1, A, B, C, or E2.
  2. 2 . The polymer of claim 1 , wherein E1 and E2 are the same as or different from each other, and are each independently a substituted or unsubstituted alkyl group; a substituted or unsubstituted aryl group; a cross-linkable group; or a combination thereof.
  3. 3 . A polymer comprising a unit represented by Chemical Formula 2-1 and an end group represented by Chemical Formula 5: in Chemical Formulae 2-1 and 5, Ar2 and Ar3 are the same as or different from each other, and are each independently an aryl group unsubstituted or substituted with an alkyl group, Ar1 and Ar4 are the same as or different from each other, and are each independently an arylene group, R1 and R2 are each a F, R3 is a hexyl group, n3 is 2, E is hydrogen; deuterium; a substituted or unsubstituted alkyl group; a substituted or unsubstituted silyl group; a substituted or unsubstituted aryl group; a substituted or unsubstituted arylamine group; a substituted or unsubstituted siloxane group; a cross-linkable group; or a combination thereof, and * is an attachment point in the polymer.
  4. 4 . The polymer of claim 3 , further comprising a unit represented by Chemical Formula 3: in Chemical Formula 3, m is an integer of 3 or 4, when m is 3, Z is CRa; SiRa; N; or a substituted or unsubstituted trivalent aryl group, when m is 4, Z is C; Si; or a substituted or unsubstituted tetravalent aryl group, Ra is hydrogen; a substituted or unsubstituted alkyl group; or a substituted or unsubstituted aryl group, Y is a direct bond; a substituted or unsubstituted alkylene group; or a substituted or unsubstituted arylene group, when Y is a direct bond; or a substituted or unsubstituted alkylene group, Z is a substituted or unsubstituted trivalent or tetravalent aryl group, and * is an attachment point in the polymer.
  5. 5 . The polymer of claim 3 , further comprising a unit represented by Chemical Formula 4: *—[C]—* [Chemical Formula 4] in Chemical Formula 4, C is a substituted or unsubstituted arylene group; a substituted or unsubstituted divalent heterocyclic group; R37 to R39 are the same as or different from each other, and are each independently deuterium; a substituted or unsubstituted alkyl group; a substituted or unsubstituted aryl group; or a cross-linkable group, k4 is an integer from 0 to 4, k5 is an integer from 0 to 3, when k4 and k5 are each 2 or higher, each occurrence of R37 to R39 is the same as or different from each other, respectively, and * is an attachment point in the polymer.
  6. 6 . The polymer of claim 1 , wherein Chemical Formula 3 is represented by any one of Chemical Formulae 3-1 to 3-4: in Chemical Formulae 3-1 to 3-4, Z1 is CRa; SiRa; N; or a substituted or unsubstituted trivalent aryl group, Z2 and Z3 are the same as or different from each other, and are each independently C; Si; or a substituted or unsubstituted tetravalent aryl group, L1 is a direct bond; or a substituted or unsubstituted arylene group, Ra is hydrogen; a substituted or unsubstituted alkyl group; or a substituted or unsubstituted aryl group, R10 to R20 are the same as or different from each other, and are each independently hydrogen; deuterium; a halogen group; a cyano group; an alkoxy group; an aryloxy group; a fluoroalkoxy group; a siloxane group; a substituted or unsubstituted amine group; a substituted or unsubstituted alkyl group; a substituted or unsubstituted aryl group; a substituted or unsubstituted heterocyclic group; or a cross-linkable group, and adjacent groups may be bonded to each other to form a ring, k1 is an integer from 1 to 4, k2 is an integer from 1 to 5, when k1 is 2 or higher, each occurrence of R10 to R19 is the same as or different from each other, respectively, when k2 is 2 or higher, each occurrence of R20 is the same as or different from each other, and * is a part that bonds to at least one of E1, A, B, C, or E2.
  7. 7 . The polymer of claim 1 , which has a weight average molecular weight of 70,000 g/mol to 2,000,000 g/mol.
  8. 8 . The polymer of claim 1 , wherein Chemical Formula 3 is represented by any one of the following structures: * is a part that bonds to at least one of E1, A, B, C, or E2.
  9. 9 . The polymer of claim 1 , wherein the C is represented by any one of the following structures: wherein: Y1 is S, O, or NR100, R30 to R33 and R36 to R39 are the same as or different from each other, and are each independently deuterium; a substituted or unsubstituted alkyl group; a substituted or unsubstituted aryl group; or a cross-linkable group, k3 is an integer of 0 to 2, k4 is an integer from 0 to 4, k5 is an integer from 0 to 3, k6 is an integer from 0 to 8, when k3 to k6 are each 2 or higher, each occurrence of R30 to R33 and R36 to R39 is the same as or different from each other, respectively, R34, R35 and R100 are the same as or different from each other, and are each independently hydrogen; deuterium; a substituted or unsubstituted alkyl group; a substituted or unsubstituted aryl group; or a cross-linkable group, and * is a part that bonds to at least one of E1, A, B, C, or E2.
  10. 10 . The polymer of claim 1 , wherein E1 and E2 are each any one of the following structures: * is a part that bonds to A, B or C, respectively.
  11. 11 . The polymer of claim 1 , wherein a is a real number from 0.4 to 1, b is a real number from 0 to 0.4, and c is a real number from 0 to 0.2.
  12. 12 . An organic light emitting device comprising: a first electrode; a second electrode provided to face the first electrode; and an organic material layer having one or more layers, which includes a light emitting layer provided between the first electrode and the second electrode, wherein one or more layers of the organic material layer comprise the polymer of claim 1 .
  13. 13 . The organic light emitting device of claim 12 , wherein the organic material layer comprising the polymer is a hole injection layer, a hole transport layer, or a layer which simultaneously injects and transports holes.
  14. 14 . The organic light emitting device of claim 12 , wherein the light emitting layer comprises an organic compound.
  15. 15 . The organic light emitting device of claim 12 , wherein the light emitting layer comprises a quantum dot.

Description

CROSS-REFERENCE TO RELATED APPLICATION(S) The present application is a national stage entry under 35 U.S.C. § 371 of International Application No. PCT/KR2021/000378 filed on Jan. 12, 2021, which claims priority from Korean Patent Application No. 10-2020-0003988 filed on Jan. 13, 2020, all the disclosures of which are incorporated herein by reference. TECHNICAL FIELD The present specification relates to a polymer and an organic light emitting device formed by using the same. BACKGROUND ART An organic light emission phenomenon is one of the examples in which an electric current is converted into visible rays through an internal process of a specific organic molecule. The principle of the organic light emission phenomenon is as follows. When an organic material layer is disposed between a positive electrode and a negative electrode, if current is applied between the two electrodes, electrons and holes are injected from the negative electrode and the positive electrode, respectively, into the organic material layer. The electrons and the holes which are injected into the organic material layer are recombined to form an exciton, and the exciton falls down again to the ground state to emit light. An organic electroluminescent device using this principle may be generally composed of a negative electrode, a positive electrode, and an organic material layer disposed therebetween, for example, an organic material layer including a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, and an electron injection layer. A material used in the organic light emitting device is mostly a pure organic material or a complex compound where an organic material and metal form a complex, and may be classified into a hole injection material, a hole transport material, a light emitting material, an electron transport material, an electron injection material, and the like according to the use thereof. Herein, an organic material having a p-type property, that is, an organic material, which is easily oxidized and has an electrochemically stable state during oxidation, is usually used as the hole injection material or the hole transport material. Meanwhile, an organic material having a n-type property, that is, an organic material, which is easily reduced and has an electrochemically stable state during reduction, is usually used as the electron injection material or the electron transport material. As the light emitting material, a material having both p-type and n-type properties, that is, a material having a stable form in both oxidation and reduction states is preferred, and a material having high light emitting efficiency for converting an exciton into light when the exciton is formed is preferred. In addition to those mentioned above, it is preferred that the material used in the organic light emitting device additionally has the following properties. First, it is preferred that the material used in the organic light emitting device has excellent thermal stability. This is because joule heating occurs due to the movement of electric charges in the organic light emitting device. Currently, since N,N′-di(1-naphthyl)-N,N′-diphenyl-(1,1′-biphenyl)-4,4′-diamine (NPB) typically used as a hole transport material has a glass transition temperature value of 100° C. or less, there is a problem in that it is difficult to use the material in an organic light emitting device requiring a high electric current. Second, in order to obtain a high-efficiency organic light emitting device which is capable of being driven at low voltage, holes or electrons injected into the organic light emitting device need to be smoothly transferred to a light emitting layer, and simultaneously, the injected holes and electrons need to be prevented from being released out of the light emitting layer. For this purpose, a material used in the organic light emitting device needs to have an appropriate band gap and an appropriate highest occupied molecular orbital (HOMO) or lowest unoccupied molecular orbital (LUMO) energy level. Since poly(3,4-ethylenedioxythiophene) doped:poly(styrenesulfonic acid) (PEDOT:PSS) currently used as a hole transport material in an organic light emitting device to be manufactured by a solution application method has a lower LUMO energy level than the LUMO energy level of an organic material used as a light emitting layer material, it is difficult to manufacture an organic light emitting device having high efficiency and a long service life. In addition, the material used in the organic light emitting device needs to have excellent chemical stability, excellent charge mobility, excellent interface characteristics with electrodes or adjacent layers, and the like. That is, the material used in the organic light emitting device needs to be minimally deformed by moisture or oxygen. Further, the material used in the organic light emitting device needs to have appropriate hole or electron mobility so