No abstract

Glass fiber-multiwall carbon nanotubes (GFMWCNTs) hybrid preforms were prepared by electrostatic assembly method. Negatively charged MWCNTs by oxidization treatment were directly adsorbed onto the surfaces of positively charged GF to form tunable structure. The thickness and morphology of GF-MWCNTs preforms can be controlled by the assembly pH value and the concentration of oxidized-MWCNTs solution. We demonstrate that GF-MWCNTs preforms have uniform and porous interconnected network structure of MWCNTs on the surfaces of GF using FESEM. The multi-scale composites with the hybrid preforms were prepared by melt compounding. The presence of MWCNTs with porous nanostructure helps in the formation of interpenetrating network with polyamide 6 (PA 6) at the interface layer. As a result, the tensile tests of these multi-scale composites exhibit higher tensile properties in comparison with composites with GF, showing a promising structural composite to replace the traditional GF-reinforced composites with limited improvement of the performance.

We developed an approach to prepare the multilayered 3D composites where aligned multiwalled carbon nanotubes (MWCNTs) were grown on the surface of quartz fiber cloths (QFCs) by chemical vapor deposition method. The morphologies of the MWCNTs-QFCs preforms were analyzed by field emission scanning electron microscopy, transmission electron microscopy, and thermogravimetric analysis. The results showed that the growth of high yield and uniform alignment of MWCNTs on the surface of QFCs could be controlled by the process. The unique MWCNTs-QFCs preforms, when served as connecting bridges for structural epoxy composites, demonstrated a significant enhancement of the interlaminar shear strength and electrical conductivity along in-plane and out-of-plane directions when compared to QFCs/epoxy composites without MWCNTs, making the MWCNTs-QFCs reinforcements meaningful in structural composites.