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The right clothing and equipment is of vital importance to the survival and effectiveness of military personnel. Advances in military textiles and personal equipment summarises key research on the design, manufacture and applications of military textiles. Beginning with an overview of design issues, part one explores anthropometric methods, psychological, colour and camouflage issues related to the successful design of military textiles. Materials and design issues in military helmets, footwear and hand wear are also reviewed. Part two goes on to consider applications of particular types of military clothing and equipment, including optimisation of body armour design, high performance ballistic protection using polymer nanocomposite technology as well as advances in materials and modelling of chemical, biological, radiological and nuclear protective clothing. Finally, Advances in military textiles and personal equipment looks specifically at designing load carriage and advanced hydration systems for military personnel. With its distinguished editor and international team of expert contributors, Advances in military textiles and personal equipment is an invaluable resource for all those working in the design, manufacture and production of military clothing and equipment, as well as for the defence industry itself.

This thesis is concerned with the development of high performance ultrahigh molecular polyethylene (UHMWPE) fibers reinforced using multiwalled carbon nanotubes (MWCNTs). A novel process has been developed, whereby, MWCNT/UHMWPE nanocomposite fibers with Young's modulus up to 137 GPa and tensile strength of ~4.2 GPa has been produced. This fiber possesses the best specific mechanical properties amongst all current commercial high performance fibers. Systematic investigations were carried out to elucidate the mechanisms of reinforcement. Firstly, systematical experimental studies were carried out to investigate the CNT reinforcing effect on nanocomposite fibers prepared with different PE molecular orientations. The overall effect can be classified into three regions. At low molecular orientation levels, the CNTs act to toughen and strengthen the nanocomposites. At the intermediate molecular orientations, the CNTs have negligible effects on the mechanical properties of the nanocomposites. At very high molecular orientations, the CNTs act to mainly stiffen and strengthen the nanocomposite. Secondly, systematic investigations were carried out to investigate the structure evolution as well as the load transfer between the embedded CNTs and that of the matrix PE. Thermal and morphological studies demonstrate that CNTs act as effective nucleation sites for PE crystal growth. The load transfer mechanisms in both the low and high molecular orientation fibers are similar. Major differences were related to CNT alignment effects. The highly oriented fibers show CNT alignment effect in the initial elastic regime, whereas the CNTs in the fibers of low molecular orientations show no appreciable alignment in the elastic regime. Finally, based on the experimental observations, a mechanistic model has been proposed to elucidate the reinforcement mechanisms. This model proposes that there exists an absorption layer surrounding CNTs. The thickness of this layer decreases as fiber molec

This paper reports the use of multiwalled carbon nanotubes (MWCNT) to reinforce and toughen gel-spun ultra high molecular weight polyethylene (UHMWPE) fibers. By adding 5 wt\% MWCNT, ultra strong fibers with tensile strengths of 4.2 GP and strain at break of similar to 5\% can be produced. In comparison with the pure UHMWPE fiber at the same draw ratios, these values represent increases of 18.8\% in tensile strength and 15.4\% in ductility. In addition, a 44.2\% increase in energy to fracture has also been observed. The mechanism of reinforcement has been studied using a combination of high resolution scanning electron microscopy (SEM) and micro-Raman spectroscopy. Carbon nanotube alignment along the tensile draw direction has been observed at high elongation ratios. Such alignment induces strong interfacial load transfer both at small and large strains to enhance the stiffness and tensile strength of the composite fiber. Consequently, the mechanical properties of the composite fiber follow closely with the rule of mixtures. Our work also reveals potential for positive deviation from rule of mixtures if the CNT alignment can be further optimized. (c) 2006 Elsevier Ltd. All rights reserved.

The tribological properties of the high-strength and high-modulus ultrahigh molecular weight polyethylene (UHMWPE) film and the UHMWPE composites reinforced by multiwalled carbon nanotubes (MWCNT/UHMWPE) were investigated using a nanoindenter and atomic force microscope (AFM). The MWCNT/UHMWPE composites films exhibited not only high wear resistance but also a low friction coefficient compared to the pure UHMWPE films. We attribute the high wear resistance to the formation of the new microstructure in the composites due to the addition of MWCNTs. Copyright (C) 2006 John Wiley & Sons, Ltd.

We report experimental observations on the drastically enhanced toughness in the high-strength and high-modulus ultrahigh molecular weight polyethylene (UFMWPE) films due to the addition of 1 wt\% multiwalled carbon nanotubes (MWCNTs). A combination of tensile and Raman spectroscopic measurements showed that the presence of MWCNTs in the composites can lead to a similar to150\% increase in strain energy density in comparison with the pure UPMWPE film at similar draw ratios. This is accompanied with an increase of similar to140\% in ductility and up to 25\% in tensile strength. We attribute the above observations to the chain mobility enhancement in UHMWPE induced by the MWCNTs. (C) 2003 Elsevier Ltd. All rights reserved.