Preparation,Structure And Properties Of Nanometer-Silica-acrylate Hybrid Latexes

Polymer nanometer-hybrid materials are the system in which polymers serve as organic phase while nano-materials are inorganic phase or the system containing composite precursors. Because of their good processability, plasticity and functionality, polymer nanometer-hybrid materials become one of the best carriers of hybrid materials. Polymer nanometer-hybrid materials have gained significant attention in the field of nanoscience and nanotechnology. The process to make the hybrids is the one of most important methods in the preparation of the high performance polymer material.In this thesis, 40-100 nm silica particles were first prepared through alkaline hydrolysis of TEOS. The factors on the effect of particle size were discussed and the optimal parameters were obtained. These silica nanoparticles were synthesized under pH 8.2, feeding rate below 0.08ml/min and rotating speed below 200r/min.The silica-sol-acrylate hybrid latexes, hydrophobic-silica-acrylate hybrid latexes, modified silica-acrylate hybrid latexes by miniemulsion polymerization were then studied. The effect on monomer conversion and particle size by the type of initiators, reaction temperature, the amount of emulsifiers, initiators and silica was investigated. The results showed that monomer droplets were the sites for polymerization with different initiator. Some homogeneous nucleation were observed in the presence of water-soluble initiator APS, yielding the slight decrease of the average diameter of the polymer particles. With the increase of temperature, the amount of emulsifier,initiator content and silica-sol, the reaction rate and monomer conversion increased while the average diameter of polymer partciles decreased. When the silica-sol was used, SiO₂ can be added up to 25 wt% vs. monomer content. On the...