Structure and mechanical properties of polyoxymethylene/multi-walled carbon nanotube composites

Toughened and reinforced POM/MWCNT composites were prepared by compounding POM with MWCNTs at low filler content. The mechanical strength and toughness of the composites were enhanced at 1 wt% MWCNT loading. The fractured surface of the composite at this loading was very rough, and a certain toughness feature was presented. MWCNTs showed an obvious nucleation effect on POM, leading to an increase of crystallization temperature and crystallization rate, and a reduction of spherulite size. The storage and loss modulus of the composites both increased at all temperatures by introducing rigid MWCNTs, indicating an improved stiffness of composites and strong entanglement between POM and MWCNTs. Under shear stress, MWCNTs were pulled-out with a skin-core structure. The failure mode of the composite was supposed to be the deformation and destruction of POM matrix around the interfacial layer under load. (C) 2011 Elsevier Ltd. All rights reserved.