Carbon Nanotubes Modified With Low Temperature Plasma And Initiated Styrene Grafting Copolymerization

Among the numerous strategies of modifying carbon nanotubes (CNTs), low temperature plasma treatment has the advantages of time-saving, clean, controllable, and through this technique can successfully trigger the olefin monomers grafted on the surface of CNTs.In this dissertation, low temperature plasma was firstly used to modify single-walled carbon nanotubes (SWNT) and multi-walled carbon nanotubes (MWNT). The effect of the modification on the structure, morphology and properties of CNTs were investigated. Meanwhile, combined with the advantages of plasma initiated polymerization, SWNT/ styrene composites was prepared through emulsion polymerization. The best reaction condition was obtained by discussing the influence factors on polymerization productivity.SWNT and MWNT were modified mainly by air,argon(Ar),nitrogen(N2) and carbon dioxide(CO2) plasma, especially focusing on the influences of plasma parameters such as trearment time and processing gas. The results of X-ray photoelectron spectroscopy (XPS) and infrared spectroscopy(FTIR) indicated the introuduction of oxygen-containing groups onto the surface of the SWNT and MWNT, such as C-O,C=O,-COO-. The air was the best modification plasma gas. The CNTs surface properties and dispersant polarity had close contact for its dispersion; the modified CNTs were dispersed well in organic solvents as toluene and anhydrous alcohol. The Raman spectrum indicated the diameter of used SWNT was 1.3 nm around and had little defect. After 20min treatment by Ar, the polar groups were introduced because the D peak of SWNT was enhanced with its integrity destroyed.Fully integrated with the double advantages of plasma surface modification and induced polymerization, the composites of SWNT and PS were prepared, mainly researched the effect of different post polymerization time, discharge time, gas flow, polymerization temperature, emulsifying agent, initiated gas on the productivity. The reaction products were characterized through FTIR, XPS, Raman spectrum and so on.