Study on the Preparation and Properties of Epoxy/PEI/Nano-Attapulgite Nanocomposites

Polyether imides (PEI) and nanoattapulgite particles organically synthesized by the active silane containing epoxide groups (OAT) were used to modify the epoxy resin (ER). The effect of the concentration of OAT on the morphology, thermal and mechanical properties of ER/PEI/OAT nanocomposites was explored in the present work. The microscopic structure of nanocomposites was investigated by Scanning electric microscopy (SEM). The results showed that a homogeneous nanoattapulgite organically-modified by silane in the polymeric matrix was obtained. SEM images showed that the morphology transformation increased with the increase of OAT content, which would lead the improvement of the impact strengths of nanocomposites. The results of mechanical and thermal measurements indicated that the introduction of PEI and OAT into the epoxy resulted in the great improvement of the impact strength and storage module. With the OAT concentration increasing, the glass translation temperature (Tg) value of nanocomposites was gradually increased. Additionally, the results of thermo-gravimetric analysis (TGA) revealed that thermal stability of nanocomposites was apparently improved in comparison to the epoxy resin systems.

Study on Structure and Property of PAN//MWNTs Composite Fibers

Concentrated sulfuric and concentrated nitric acids treated multi-walled carbon nanotubes (MWNTs) and polyacrylonitrile (PAN) were fabricated via a conventional wet spinning process. Mechanical properties of the composite fibers were studied by tensile testing and structures of the fibers were investigated via SEM and DMA. The results showed that the strength, storage modulus and glass translation temperature of the composite fiber containing 5% content of MWNTs were improved compared with those of pure PAN. The fiber with 5wt% MWNTs showed its conductivity of an order of 10-3S/cm.