Preparation Of Hollow Microspheres And Ordered Macroporous Materials By Polymer Template Method And Its Application

Hollow microspheres and ordered macroporous materials that can effectively improve the main functions of the advanced materials have broad application prospects in many important fields, became a focus of material research. In order to solve the problem of serious environmental pollution, fast detection and analysis of environmental pollutants is very important. This paper successfully achieved good quality of PS colloid crystal, monodisperse hollow PANI, Ag microspheres, adjustable aperture of ordered macroporous PANI, Ag film, and preliminary study the application of ordered macroporous materials in environmental analysis. The research work and main conclusions of this paper are as follows:1、The preparation of PS microspheres and their self-assemblyDifferent particle size of PS microspheres were synthesized via the emulsifier-free emulsion polymerization and dispersion polymerization. Take the PS microspheres as colloid particles, PS colloid crystal was prepared by vertical deposition method. The quality of the PS colloidal crystals were studied under the conditions of different size, different concentrations of PS microspheres. The results were as follows:PS microspheres prepared via emulsifier-free emulsion polymerization and dispersion polymerization were uniform particle size, single dispersion; The particle size of PS microsphere in the range from220to520nm, The PS colloidal crystals prepared by vertical deposition method were good quality, higher order, and face-centered cubic close-packed structure; After PS microspheres particle size were determined, the PS colloid crystals arranged orderly most closely when the concentration of PS solution was0.1%; The transmission spectra of prepared PS colloid crystal conform to the Bragg diffraction phenomenon.2、The preparation hollow PANI and Ag microspheresPS microsphere surface was modified by dopamine. Core-shell type PS/PANI microspheres were achieved by using the modified PS microspheres as substrate, aniline as reaction monomers and potassium persulfate as oxidant, after dissolving PS microspheres, the different shell thickness of PANI hollow microspheres were obtained. With the modified PS microspheres as substrate, after adsorption of silver ion ammonia, take glucose as the reducing agent, the different shell coated density of core-shell type PS/Ag microspheres were prepared, finally dissolving of PS microspheres, hollow Ag microspheres were obtained. The results were as follows:After modified PS microspheres by dopamine, the surfaces of microspheres slightly rough; When aniline concentration was from0.5×10-3to2.0×10-3mol/L, core-shell type PS/PANI composite microspheres were prepared; The shell thickness of PANI hollow microsphere increased accordingly with the increase of reaction aniline monomer concentration increased; When silver nitrate concentration was0.6×10-1to2.4×10-1mol/L, the different coating density of PS/Ag composite microspheres were obtained; The prepared hollow Ag microspheres showed good sphericity.3、The preparation of ordered macroporous PANI and Ag filmWith PS colloidal crystal as template, in three electrode system, using cyclic voltammetry, controlled potential from-0.3to0.9V, aggregated aniline by electrochemical, ordered PS/PANI composite array was obtained. After dissolving PS colloidal crystal template, the ordered macroporous PANI thin films were prepared. PS Colloidal crystals were modified by dopamine, after adsorption of silver ion ammonia on surfaces and formaldehyde as reductive, PS/Ag composite array were obtained. finally dissolving PS colloidal crystal template,different aperture sizes of ordered macroporous Ag films were prepared. The results were as follows:The morphology of polyaniline that aggregated by electrochemica on the ITO conductive glass was nanofibers shaped; Deposition of polyaniline with colloidal crystals as a template, its morphology copied the order of colloidal crystal template; The prepared macroporous PANI film orderly, good quality; In the prepared PS/Ag composite array,the Ag particles that adsorbed on the surface of PS microspheres was granular; In the aperture size range from165to450nm, the prepared ordered macroporous silver membrane was highly ordered and the quality was good.4> Ordered macroporous membrane application in the environmental analysisTake different types of PANI film applied to pH sensor. Using rhodamine6G aqueous solution as the probe molecule, Raman enhancement was studied of different kinds of Ag film. The results were as follows:The order of PANI film for acid, alkali response potential value: ordered macroporous PANI films> PS/PANI composite array> PANI film; The response potential value of ordered macroporous PANI film in acidic and alkaline conditions were66.75mV/pH,60.43mV/pH; Such conductive polymers pH sensor are expected to be used to monitor the pH changes of the water. The Raman enhancement order of different types of Ag films: Macroporous Ag films> PS/Ag array; Within the aperture size range from165nm to450nm, the enhancement effect of Rhodamine6G increaseed accordingly with the aperture size of macroporous Ag membrane increased; Such SERS substrates is expected to be used in environmental detection of little harmful material.