Polyethylene ultra high modulus, phase structure

Recently, various techniques that produce highly oriented linear polyethylene with a ultra high modulus (hereafter, referred to as UHMPE) have been developed. In this section, we will examine the structure of the UHMPE that was prepared by highly drawing a dried gel [69]. Even if bulk polyethylene is uniaxially highly drawn by a normal method at a temperature between the Tg and Tm, the phase structure is essentially similar to the undrawn sample. That is, it involves three phases of the crystalline and two noncrystalline phases, although the mass fraction and detailed content of each phase are somewhat different. However, UHMPE samples may have a particular phase structure. 

Figure 9.18 Schematic representation of the structure of the crystalline phase in ultra-high-modulus polyethylene (constructed for p = 0.4). (Reproduced from Gibson, A.C., Davies, C.R. and Ward, I.M. (1978) Dynamic mechanical-behavior and longitudinal crystal thickness measurements on ultrahigh modulus linear polyethylene - quantitative model for elastic-modulus. Polymer, 19, 683. Copyright (1978) I PC Business Press Ltd.)...

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