Mixed ionic surfactant system for stable susp ension of multiwall ed carbon nanotubes

Carbon nanotubes ( CNT) and CNT materials have attr acted widespread interest in researc h and increasing industrial attention. These materials h ave extra ordinary conductivity that varies with length c hange۱. Car bon nanotub es have many applications in polymer industry۲ and water treatment۳.Carbon nanotubes have high V anderWaals interaction energy that causes a strong bundling of carbon nan otubes. Thi s high interaction force makes t he dispersion stability a challengi ng task. Dif ferent way s have been examined to solve this problem. But using the surfactan t is one of the chemical methods that does not impact on t he nanotube properties. Herein, we investigated the dispersive effects achieved by surface-acti ve agents on MWNTs. Dodecyl trimethyl ammonium bro mide (DTA B) is a week dispersi ve agent in bellow its critical micelle concentration (cmc). But wh en DTAB is mixed with sodium d odecyl sulf ate (SDS), in high percent of DTAB, shows littl e dispersion and when t he percent of SDS is higher than D TAB, due to synergis m effect, sh ows good dispersion. W e should note that there is limitation in choosing the percent of surf actants in mixture. Ionic surfactan ts make ion pairs in som e percent and sediment.

کلیدواژه ها:

dispersio n ، carbon nanotube ، surfactant.