Polyimide precursor prepared by using polycyclic monomer including trifluoromethyl group and flexible polyimide obtained by using the same

A polyimide precursor compound represented by the following Chemical Formula I:

• wherein, in the above Chemical Formula I:
• X is a combination of a dianhydride monomer represented by the following Chemical Formula 1 and a diamine monomer represented by the following Chemical Formula 2,
• Y is a combination of a dianhydride monomer represented by the following Chemical Formula 3 and the diamine monomer represented by the following Chemical Formula 2,
• a is an integer of 1 to 1,000,
• b is an integer of 1 to 1,000,
• n is an integer of 1 to 50,000,
• a:b is 80:20 or 97.5:2.5, and
• wherein, in the above Chemical Formula 1, Chemical Formula 2 and Chemical Formula 3:
• each of R1 to R4 is independently H, —CF3, a substituted or unsubstituted linear or branched C1-20 alkyl group, a substituted or unsubstituted C6-20 aryl group, or a substituted or unsubstituted C4-20 heteroaryl group containing at least one hetero atom(s) from N, O, or S,
• at least one of R1 and R2 is —CF3, the alkyl group, aryl group, or heteroaryl group substituted with —CF3,
• at least one of R3 and R4 is —CF3, the alkyl group, aryl group, or heteroaryl group substituted with —CF3, and
• A1 is represented by the following Chemical Formula 4 or Chemical Formula 5:
• wherein, in the above Chemical Formula 4 and Chemical Formula 5:
• each of R5 to R8 or R9 to R12 is independently H, —CF3, a substituted or unsubstituted linear or branched C1-20 alkyl group, a substituted or unsubstituted C6-20 aryl group, or a substituted or unsubstituted C4-20 heteroaryl group containing at least one hetero atom(s) from N, O, or S, and
• at least one of R5 to R8, or at least one of R9 to R12 is —CF3, the alkyl group, aryl group, or heteroaryl group substituted with —CF3.