Influence of Carboxyl Group Content on the Quality of Photonic Crystal Self-Assembled by Latex Spheres

Polystyrene-poly (methyl methacrylate)-poly (acrylic acid)(PS-PMMA-PAA) latex spheres were obtained through the copolymerization of active monomer styrene(St),methl methacrylate(MMA) and carboxyl acid(AA) possessing functional carboxyl group,ammonium persulfate((NH₄)₂S₂O₈) was also added as initiator,then high quality photonic crystal(PC) was prepared through the vertical deposition of as prepared latex spheres.The morphology and properties of latex spheres and PC were characterized by the field emission Scanning Electron Microscopy(SEM),Dynamic Light Scattering(DLS)and conductivity meter.The optical property and water retention capacity were evaluated by the spectrometer and contact angle analyzer.Results demonstrate that the carboxyl group at the surface of latex sphere can not only increase the hydrogen bond interactions between latex spheres,but also improve the water retention capacity of latex spheres.The cracks in PC are eliminated under simple self-assemble condition,and high quality PC is fabricated.