Fabrication And Characterization Of Membranous Composite Based On Carbon Nanotubes And Polyester

Carbon nanotubes have many excellent properties and potential applications especially in composite field, although some barriers exist. To be more cost effective, better and more feasible way of fabricating membranous composite from normal multi-wall carbon nanotubes (MWNTs) need to be explored.Dispersion of MWNTs was studied in different solvent and with different adding time for surfactant. With the aid of Field Emission Scanning Electron Microscope (FESEM) and Laser Light Scattering Spectrometer (LLS), it is proved that a more uniform and stable carbon nanotubes'suspension used de-ionized water as solvent, and added surfactant into suspension after being ultrasonic vibrated for 1 hour. MWNTs with different morphology were both dispersed in the same way and finally found L-shape is the better choice for nanotubes dispersion. The above carbon nanotubes'dispersion was also used to fabricate nanotubes-based membranous composite in two way, in which the method and some parameters were analyzed.One is based on carbon nanotubes buckypaper, which means the buckypaper was infiltrated by polymer solution to become a composite sheet. MWNTs were dispersed, then filtrated to become a buckypaper. Keys of process and parameters were discussed with the help of macro and micro analysis. The buckypaper was then infiltrated by Polyester solution to be a buckypaper/PET membranous composite. FESEM was used to observe the surface and cross section. Contact angle and linear resistance were also studied.The other way is based on electrostatic spun membrane of nanofiber, on which MWNTs would be deposited. Electrospinning is a novel method to produce nanofibers from polymer solution. By this process, fibers with diameter around 100nm can be produced using electrostatic field of high voltage which compel the polymer solution to jet and deposit as a membrane. Meanwhile, the diameter of fibers produced by traditional way, such as dry spinning, wet spinning, melt spinning and gel spinning, is in the range of several to several hundred micrometers. Because of the small diameter and large specific surface area, nanofiber produced by electrostatic spinning could be widely used in filtration and membrane materials. Furthermore, it also has many potential application in biomaterials and CNTs enforced composites.The study made 2 kinds of nanofiber membrane, and tested by DSC and FESEM. The size and distribution of holes in membrane are analyzed with the help of IMAGE J. Via the orthogonal fabrication experiment, CNTs/PET electrostatic spun membrane composite are fabricated by vacuum assisted filtration. By various analytical method, we have grasp the fabrication and parameters setting of the two membranous composites with different properties, buckypaper/PET membranous composite and CNTs/PET electrostatic spun membrane composite, which are composed of the same component, but manufactured in different way.