In general Formula (I), Ar1 is a tetra-valent organic group having a benzene ring or an alicyclic hydrocarbon structure, Ar2 is a di-valent organic group, R is each independently methyl or phenyl, and n is 1?5.
According to an embodiment of the present disclosure, Ar1 is a tetra-valent organic group having a monocyclic alicyclic hydrocarbon structure or a bridged-ring alicyclic hydrocarbon structure.
According to another embodiment of the present disclosure, Ar2 is a di-valent organic group having a monocyclic alicyclic hydrocarbon structure.