Structural evolution and its effect on optical absorption/emission behavior of fluorene-thiophene conjugated alternate copolymers and naphthalene-thiophene conjugated alternate copolymers and polystyrene-poly-3octylthiophene-polystyrene triblock copolymer of upon isothermal heat treatment at elevated temperatures, and the well £k-£k stack at interchain species (ordered aggregates) be formed in dilute solutions and its effect the UV-vis and PL spectra. These conjugated polymer with mono- or disubstituted with alkyl side chain and with alkyl or alkoxyl flexible side-chains. This studied by means of a combination of polarized light microscopy, x-ray diffraction, ultraviolet-visible spectroscopy, light scattering spectroscopy and photoluminescence spectroscopy. According to the results of the experiment, the fluorene-based polymer can be observed emission from order aggregate in the solution state, but not found in naphthalene-based and triblock copolymer.