Copolymer, electroluminescence device material including copolymer, and electroluminescence device

A copolymer, comprising a structural unit represented by Chemical Formula 1, a structural unit represented by Chemical Formula 2, or a combination thereof:

• wherein, in Chemical Formula 1 and Chemical Formula 2,
• R1 is a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted monovalent aromatic hydrocarbon group having 6 to 30 carbon atoms, a substituted or unsubstituted monovalent aromatic heterocyclic group having 5 to 30 ring-member atoms, or —Y—N(Ar2)(Ar3), wherein Y is a substituted or unsubstituted divalent aromatic hydrocarbon group having 6 to 30 carbon atoms, Ar2 and Ar3 are each independently a substituted or unsubstituted monovalent aromatic hydrocarbon group having 6 to 30 carbon atoms, or a substituted or unsubstituted monovalent aromatic heterocyclic group having 5 to 30 ring-member atoms,
• R2 and R3 are each independently a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted monovalent aromatic hydrocarbon group having 6 to 30 carbon atoms, or a substituted or unsubstituted monovalent aromatic heterocyclic group having 5 to 30 ring-member atoms, wherein each R2 is the same or different, and each R3 is the same or different,
• optionally wherein two R2(s) are combined with each other to provide a ring, optionally wherein two R3(s) are combined with each other to provide a ring, and optionally wherein one or more R2(s) is combined with one or more R3(s) to provide a ring,
• X1 and X2 are each independently a carbon atom (C) or a silicon atom (Si), and
• Ar1 is a substituted or unsubstituted divalent aromatic hydrocarbon group having 6 to 30 carbon atoms, or a substituted or unsubstituted divalent aromatic heterocyclic group having 5 to 30 ring-member atoms.