Impact of Functional Groups in MWCNT on Surface Hydrophilicity, Mechanical and Thermal Properties of Polystyrene/CNT Composites

We prepared nanocomposites of MWCNTs/polystyrene via a solution casting method, and DI water was used as coagulation bath. The influence of pristine and two functionalized MWCNTs on surface morphology, thermal properties and mechanical properties of MWCNT/polystyrene composites were extensively discussed. Analysis of SEM shows that the porous structures with narrow size distribution from micro- to nano-size appear in all composites, which decrease the tensile strength of the composites. Despite the glass transition temperatures (Tg) of all the composites lower compared with Tg of pure polystyrene, which increase with the loading of MWCNTs. The mechanical properties of the composite with 5 wt.% MWCNTs are enhanced greatly, and the phenomenon is especially pronounced for the addition of the MWCNT-OH. (paper)