Preparation and Research of Comb Polyacrylamide and Calcium Phosphate Nanomaterials with Surfactant
|School||East China University of Science and Technology|
|Course||Materials Science and Engineering|
|Keywords||surfactant amphoteric polyacrylamide comb amorphous calcium phosphate liquid crystalline phases|
Surfactant is a kind of widely used materials. In this project, on one hand, we synthesized polyacrylamide by using quaternary ammonium-one kind of cationic surfactant as one reagent, later on as synthesized polyacrylamide was utilized to synthesize amphoteric comb like polyacrylamide with high properties. On the other hand, we synthesized amorphous calcium phosphate of different structures by using liquid crystal phase formed by self-assembly of non-ionic surfactant, which really lays the foundation for the future application of calcium phosphate in biomedicine.Polyacrylamide (abbreviation is PAM) is one of the earliest and the most widely used paper additives in the application of the paper industry. Under the effect of inhibitor, dimethylamino ethyl methacrylate (DM) reacts with bromododecane and as a result methacryloyl ethyl bromide dimethyl dodecyl ammonium generates. Then under the effect of promoter, initiator and emulsifier, the quaternary ammonium obtained reacts with acrylamide (AM) through emulsion polymerization and as a result amphoteric comb polyacrylamide generates which is the final product. The structure characterization of products was by FTIR,2H NMR, viscosity, optical microscope and SEM. The study showed that the as prepared PAM had long branched chain and comb structure. The molecular weight of the polymer was1.92x105, the solid content was94.5%. The polymer showed a typical characteristic of amphoteric compound, while the SEM images demonstrated it had obvious comb-like branched structure. The preparation and application of amphoteric polyacrylamide are highlighted which surpasses anionic/cationic polyacrylamide and comb polyacrylamide is the most promising research focus. This article provides a theoretical and experimental basis for further application in industry of paper enhance and tertiary oil recovery.One major constituent in skeletal tissues, such as bone and teeth, is calcium phosphate (CaP). In bone, the mineral growth, final composition and morphology of CaPs are modulated by organic collagen matrix and other biomacromolecules in extracellular matrix. It would be very interesting to explorehow the physicochemical properties of CaPsend up during bone mineralization in the presenceof organic matrix. In this project, liquid crystalline phases (LCPs) formed by surfactant self-assembly were utilized to mimic the collagen matrix in bone, for the study of CaP morphogenesis in organic templates. CaP formation inLCP templates with different structures was explored, includinglamellar phase (La),normal hexagonal phase(H1), bicontinuous cubic phase (I1), and reverse hexagonal phase(H2). Two different reaction systems were investigated, namely beaker method and petri dish method. The obtained CaP particles were primarily examined by Transmission Electron Microscopy (TEM) and Scanning Electron Microscopy (SEM) for the morphology. CaP rods with diameters in the range of6-20nm and sheets with width of～250nm and thickness of a few nanometers were successfully obtained from H2and La LCPs. Moreover, faceted particles with micrometer dimensions were formed from H1and I1templates.