Due to the accumulated van der Waals attraction, the separation of single-walled carbon nanotubes (SWNTs) has been a challenge. This thesis focus on theoretical modeling and study of separating SWNT array in electrolytes and by chemical functionalization. First, the swelling behavior of SWNT fibers in superacid as well as the sudden collapse of such dispersion with introduction of water are studied by Derjaguin-Landau-Verwey-Overbeek (DLVO) theory. A simple kinetic model for the charging mechanism of SWNT is proposed. Optimization of the controlled parameters of the model has been carried out. Second, we designed a tensegrity structure with three (5,5) SWNTs connected by nine polyethylene chains. One of relative strong connection ways between polyethylene and tube cap is constructed. Structure optimization and molecular dynamics simulation are performed to analyze the stability changes in such and several similar structures by adding some or removal one chain.