Research On Preparation, Essembly And UV-curing Property Of Polymerizable Lyotropic Liquid Crystal Monomer

In this paper, the assembly and research development of lyotropicliquid crystals (LLCs) are introduced. Then, the synthesis, self-assemblyand UV-curing behavior of the polymerizable LLCs are also studied. Andin the end we make a prospect of the application probability in membranematerials.In this thesis, a polymerizable LLC monomer was preparaed first, andthe self-assembly behavior of the monomer with water in methanol wasdiscussed, followed by UV-curing and nanostructure retention. Finally, theLLC was coated on a PET membrane to form composite membranematerials and the application in membrane materials was proposed. Apolymerizable LLC monomer was synthesized by a convenient routestarting from3,4,5-trihydroxybenzoic acid via esterification followed byetherification, acrylation and finally neutralization and generated atrifunctional group monomer with three branches, and the chemicalstructure and purity were confirmed by IR and1H NMR spectral analysis.We demonstrated the self-organization behavior of monomer1with deionized water in methanol at room temperature based on the theoreticalcalculation of critical packing parameter. And the results revealed that, thefine lamellar (L) phase could be formed when the solution of monomer1/water (8/2) was allowed to equilibrate for at least48h after stirred24h atambient temperature in the presence of methanol (90%of the total amount)as a cosolvent, and the assemblies were confirmed by PLM and XRDanalysis. The preparation of inverted hexagonal (HII) phase was similar tothat of L phase, and the best ratio of monomer1/water we found until nowwas92/8. After that, we added different kind of photoinitiators to the LLCsystem and polymerized by UV-curing. The results show that, the acrylateconversion could reach up to78%when the LLC system containingphotoinitiator Darocur2959was exposed to30mW/cm2365nm UV lightfor30min, under which circumstances both L and HIIphases got retentionto some extent confirmed by XRD and PLM. Finally, the LLC containingphotoinitiator Darocur2959was coated on a nanofibrous PET membraneand polymerized, we could get composite membrane materials withsmooth surface morphology and pore diameter of1μm characterized bySEM images. The composite membrane materials obtained in this wayhave the advantage of uniform pore size, strong controllability, and goodcompatibity between the two layers, which makes it hopeful to exhibit afurther application in water filtration if the mechanical behavior could beimproved by optimizing the preparation technology.