| 초록 |
Optical properties of photonic crystal film were investigated by tuning photonic band gap (PBG). The lamellar-forming photonic films were prepared by nearly symmetric poly(styrene-b-2-vinyl pyridine) (PS-b-P2VP) block copolymers. Molecular weight of PS-P2VP is 25k-25k, 52k-57k, 57k-57k, 75k-66.5k, 190k-190k(g/mol), respectively. The lamellar stacks, which are alternating layers of hydrophilic and hydrophobic moiety of PS-b-P2VP, are obtained by exposing the spin coated film under chloroform vapor. The band gaps of the lamellar films interestingly varied after immersion into the quaternizing solvents containing 5wt% of iodomethane solubilized in n-hexane. Reflection color of photonic film was measured by uv-vis spectrophotometer. The change of pH gradation, metal ions and solvents of films can be changing the photonic band gap by molecular weight of PS-b-P2VP. The methods of control of reflection color show the shift of wavelength which is red shift or blue shift. |
