High performance fibers UHMWPE

Table 10.3 Comparison of mechanical properties of various commercial high-performance fibers (Kim and Mai, 1998) and 5wt% MWCNT/UHMWPE fiber (Ruan etai, 2006)...

The ballistic properties of high performance fibers such as ultra high molecular weight polyethylene (UHMWPE) and aramid and their composites are very well known. The ballistic properties of flax, hemp, and jute fabric reinforced PP composites processed by hot compression molding have also been investigated. It has been shown that flax composites exhibited better properties when compared with hemp and jute composites [48]. 

Figure 8.1. Overview of high performance fibers mechanical properties. PET = poly(ethylene terephthal-ate), UHMWPE = ultra high molecular weight polyethylene, PBO = poly(benzoxazole), M5 = PIPD or poly[di-imidazo-pyridinylene-(dihydroxy phenylene)]. The p-aramids included in the area are Kevlar, Twaron, Technora and SVM (Armos, Rusar) fibers. The latter fiber tjipe accounts for the high mod-ulus/high tenacity area of aramids (Adapted from ref. [6]). For chemical structures see Scheme 8.1...

Because the excellent mechanical properties of UHMWPE fiber are the result of high drawn ratio during the fiber processing, evident fibrils are often found on the surface of the high-performance fibers, as shown in Fig. 2.24. 

In addition to para-aramid and UHMWPE fibers, other types of polymer have also been developed for nse in bullet-proof applications. Table 10.1 (Herakovich, 1998) summarizes the current high-performance polymer fibers. It shoirld be mentioned that there still exists a big gap in mechanical properties between the commercial fibers and the theoretical values, as shown in Table 10.2 (Herakovich,... 

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