Preparation And Separation Of Polymer/Inorganic Hybrid Materials Via SI-ATRP

Polymer/inorganic hybrid material is a novel type of functional polymer for adsorption and separation, and is developed rapidly in recently years. Surface-initiated atom transfer radical polymerization (SI-ATRP) was one of the most popular methods for preparing the hybrid materials because this technique allows the synthesis of well-defined polymers on massive substrates and can tolerate functional groups and trace of impurities. In this paper, three kinds of polymer/silica gel hybrid materials were prepared via SI-ATRP, and their application in bioseparation was investigated. The main results have been obtained as follows:1. Functional monomer,5-vinyltetrazole (VT), with strong acidity and coordination was synthesised. VT was polymerized on the surface of silica gel via SI-ATRP technique in aqueous solution to prepare polyvinyltetrazole (PVT)/silica gel hybrid materials for the first time. Different chain lengths of VT molecular layer were obtained by adjusting the molar ratio among monomer, catalyzer and ligand. The resulting hybrid materials were applied as stationary phase for cation exchange chromatography. The results showed that the prepared materials have a certain separation ability to the mixture of proteins, cytochrome C, ribonuclease and myoglobin. The retention time of proteins were increased with chain length of VT, indicating that the stationary phase with different adsorptive function could be obtained by controlling the polymerized conditions in the preparation of stationary phase via ATRP technique.2. The monomer, acrylic acid, was polymerized on silica in aprotic solvent by SI-ATRP. Elemental analysis showed that AA was grafted successfully on silica, with the grafted amount 1.60 mg/m2. The poly(acrylic acid)/silica hybrid material was applied as stationary phase for cation exchange chromatography, five proteins mixture (lysozyme, a-chymotrypsin, cytochrome C, ribonuclease and myoglobin) could be separated with good performance.3. The method for the preparation of sulfo-based hybrid material with Sodium 4-styrenesulfonate via SI-ATRP in DMSO was preliminary studied. The grafed amount of poly(sodium 4-styrenesulfonate) on hybrid materials was low with only 0.27 mg/m2 by the polymerization system described in this paper. The separation efficiency of lysozyme, a-chymotrypsin, cytochrome C, ribonuclease and myoglobin on the hybrid materials was low under cation exchange chromatography mode. Therefore, this route need further studying and improving.