Dissertation > Excellent graduate degree dissertation topics show

Preparation of Chiral Organic-inorganic Hybrid Mesoporous Materials Using Achiral Surfactants as Templates

Author: BiLiFeng
Tutor: YangYongGang
School: Suzhou University
Course: Polymer Chemistry and Physics
Keywords: cationic surfactants organic-inorganic hybird silicas helical chiral co-structure-directing agent phase transition
CLC: TB383.1
Type: Master's thesis
Year: 2010
Downloads: 81
Quote: 0
Read: Download Dissertation

Abstract


Organic-inorganic hybrid helical silicas were prepared using achiral cationic surfactants as supramolecular templates and chiral alcohols as co-structure-directing agents in the 25 wt% aqueous ammonia and NaOH solutions. Critical micelle concentrations of the surfactants can be reduced with the addition of the chiral alcohols which drive the formation of worm-shaped micelle and phase transition. The molecular chiral information can be transmitted to a supramolecular and showed in another form, such as helical structures. This method offers us an opportunity to fabricate chiral mesoporous materials through a simple approach. Helical organic-inorganic hybrid silicas containing different organic bridging groups such as 1,2-ethylene, methylene, 1,2-ethenylene, 1,4-phenylene were obtained. Helical mesporous hybrid silica nanorods, nanofibers, and M?bius Nanorings were obtained. Moreover, hierarchical porous structures, nanofibers with lamellar pores on their surfaces and concentric circular or rod-like pore channels inside, were obtained. The molar ratio of the co-structure-directing agent/surfactant is the key factor on controlling the morphology and pore architectures. For periodic mesoporous organosilicas, with bridging groups uniform distribution inside the walls, their groups bridge between the two silica atoms, which can enhance accessibility in absorbance and catalysis appliacations and sening devices, and thus gain the opportunities fou further modification. The formation mechanism was studied by taking field-emission electron microscopy and transmission electron microscopy images after different time.

Related Dissertations

  1. Evaluation of Image Quality of Megavoltage Computed Tomography for Helical Tomotherapy Unit and Aplication for Dose Recalculation,R730.5
  2. Study of the Temperature Distribution Model and Designing Method for Efficient Shell-and-Tube Heat Exchangers,TQ051.5
  3. Low phase transition temperature VO 2 Films,TN304.055
  4. Investigation on Vortex-Induced-Vibration of Flexible Risers with Buoyancy Modules,TB123
  5. Downhole drilling motor stator helical surface milling technology,TG54
  6. Multi-layer multi sublattice study the physical properties of thin film materials,TB383.2
  7. Elongated inner spiral surface NC machining process simulation study,TG659
  8. Voltage current-limiting fuses pre-arcing time current characteristic simulation,TM563.1
  9. The Spin-wave Excitations of the Collinear Antiferromagnetic Phase in Iron Pnictides,O469
  10. Study on the Melting Transition and Creep Motion of Two-Dimensional Vortex Lattice Using Computer Simulation,O511
  11. Thermoelectric properties of nano - PbTe under high pressure,O469
  12. Phase Transformation Research of Crystal Silicon Induced by Axial Compress and Nanoindentation,TB302.3
  13. La, Ce doped iron oxide nanoparticles and surface adsorption phase transition behavior of,TB383.1
  14. Study on Dean Vortices and Its Heat Transfer Enhancement Characteristics in Helical Tubes,TK124
  15. Parametric design of the diesel engine inlet passage,TK422
  16. Rasearch on Finite Element Analysis of Modified Helical Gear Pair for Crane Reducer,TP391.7
  17. An Analysis on Meshing Performance of Offset Cylindrical Worm Gearing and a Study on Worm Processing,TH132.44
  18. Studies on the Elastohydrodynamic Lubrication of Involute Helical Gears,TH117.2
  19. A Design and Study of Four-wheel-adsorption Wall-climbing Robot,TP242
  20. Mechanism Research on Suppression of Vortex-induced Vibration of Deep-water Top Tension Riser by Helical Strakes,P75
  21. The Mass-radius Relation of Rotating Neutron Star under Color Superconductivity Phase and Latent Heat from Spin One Color Superconductivity Phase Transitions,P145.6

CLC: > Industrial Technology > General industrial technology > Materials science and engineering > Special structural materials
© 2012 www.DissertationTopic.Net  Mobile