Preparation And Performance Research Of Micro-nano Hierarchical Poly(S-co-HEA)/Ag Composite Microspheres

With surface hydroxylation polystyrene microspheres as template, the nanocomposite microspheres with hierarchical structure prepared by in situ reaction load inorganic particles (such as silver, silica, etc.). This kind of composite microspheres not only combine with physical and chemical properties of inorganic materials and polymer materials, but also effectively overcome the restrictions of reunite and oxidation on materials applied. In addition, the composite microspheres with hierarchical structure have advantages of high specific surface area, stable structure, and good dispersion, and show good structure material properties. The main content of this research is:1) the preparation and morphology structure regulation of hydroxylation polystyrene/silver (poly(S-co-HEA)/Ag) nanocomposite microspheres; 2) the application research of poly(S-co-HEA)/Ag nanocomposite microspheres on surface enhanced Raman scattering base construction and catalytic reduction methylene blue; 3) the preparation of morphology controllable poly(S-co-HEA)/ Ag/SiO2 nanocomposite microspheres and its performance research on catalytic degradation organic dyes.The specific content in the research are as follows:1. The morphology controllable research of poly(S-co-HEA)/Ag nanocomposite microspheres:With hydroxyl functional polystyrene microspheres as the template, and diethanolamine (DEA) as the reductant, the composite microspheres were prepared by chemical reduction deposition method. In order to achieve different morphology of polystyrene/silver nano composite microspheres, the silver particle size and distribution on polystyrene microsphere surface was researched by adjusting the amount of DEA, silver nitrate concentration, reaction temperature and the amount of polystyrene surface hydroxyl groups. The results show:when the adding amount of silver nitrate is 5 mL (0.2 mol/L), and the adding amount of DEA were 0.1 g,0.3 g and 0.5 g, the poly(S-co-HEA)/Ag nano composite microspheres with micro/nano hierarchical structure were prepared, and the silver particles on microspheres surface presented different aggregation states, which were small and sparse, large and dense, small and densely respectively.2. The surface enhanced Raman scattering and catalytic performance study of poly(S-co-HEA)/Ag nano composite microspheres:The main distinction of morphologies of poly(S-co-HEA)/Ag nanocomposite microspheres is the difference particle size and distribution of silver particles on the polystyrene microsphere surface. So the surface enhanced Raman Effect and catalytic effect of different composite microspheres showed certain regularity for the particle size and distribution of nanosilver. The test results showed that:Three typical morphologies of polystyrene/silver nano composite microspheres showed significant Surface enhanced Raman Effect. And the poly(S-co-HEA)/Ag nano composite microspheres with large and dense silver particles on surface showed the most remarkable surface enhanced Raman performance. The composite microspheres with the small and dense silver particles showed the most significant catalytic performance.3. The preparation and catalytic performance research of poly(S-co-HEA)/Ag /SiO2 nanocomposite:Using hydroxylation polystyrene as the template, DEA as the reducing agent and catalyst, adjusting the silver nitrate reduction time before joining tetraethyl orthosilicate, realized the control of silver particles size and distribution and the load effect of silica. Poly(S-co-HEA)/Ag/SiO2 nanocomposite microspheres with morphology differences showed different catalytic performances. The results showed that:The silver nitrate reduction time was a key influence factor in the reaction process of the final morphology of composite microspheres. When silver nitrate reduction for a short time (15 min), silver seeds were small and sparse, and got raspberry composite microspheres; While silver nitrate reduction for a long time (60 min), silver seeds were large and dense, and got core-shell structure composite microspheres. The raspberry morphology composite microspheres prepared by 15 min reduction of silver nitrate, showed good adsorption performance, and good catalytic properties.