Application Of Supercritical Co <sub> 2 </ Sub> Preparation Of Uracil Molecules Imprinted P (an-co-maa) Copolymer Membrane

Molecular imprinting was an effective means of encoding information such as molecular shapes and molecular functions in the field of macromolecular material on a molecular scale. In molecular imprinting progress, templates and monomers are pre-arranged by reversible covalent bindings or noncovalent interactions during the progress of polymerization and then templates are removed from the polymer materials, thus recognition sites which contained template molecular shape, size and charge distribution are created in polymer materials. Molecular imprinting membrane could be prepared by molecular imprinting and membrane technology.Supercritical fluid has been attracted more interesting. It is well known that many substances such as CO₂ above the critical temperature (T_c) and the critical pressure (P_c) were termed supercritical fluid. It has some distinctive properties which include gaslike viscosity and diffusity, liquidlike density and dissolvability. Small changes in temperature and pressure could cause dramatic changes in the density, viscosity and dielectric properties of the fluid, which makes it a tunable solvent. Supercritical fluid technology referred as "Green Chemistry Technology" has been developed to form polymeric materials such as microspheres, porous fibers, porous foams and porous membranes. Most of the polymer membranes in use were prepared by the immersion precipitation processes. And the application of supercritical CO₂ (SCCO2) has been attracting attentions in the preparation and modification of polymer membranes.In this study, we use uracil(URA)as template molecule, use acrilonitrile (AN) as membrane formation segment, use MAA which have -COOH group as function segment, using supercritical CO2 as non-solvent, prepared uracil imprinting membrane by phase inversion imprinting method. Through adjusting the temperature and pressure of supercritical CO2, more recognition sites were formed to improve the recognition ability of polymer materials. And analyzed the interaction between copolymer materials and template molecule by FT-IR, observed morphology of resultant membrane by SEM and AFM and checked the selective ability of membrane...