On the Determination of the Elastic Modulus of Ultraoriented High-Strength Film Threads Obtained by Drawing of Ultra-High-Molecular-Weight Polyethylene Xerogels

Resumo

The influence of the gauge length l₀ of a sample on the modulus E of ultraoriented film filaments of ultra-high-molecular-weight polyethylene (UHMWPE) has been elucidated. The filament samples are obtained by a multistage orientation drawing on a contact heater with achieving extremely high draw ratios as large as λ = 120. Precursors were xerogels prepared by the drying of 1.5% UHMWPE gel solutions in decalin. A noticeable gain in “methodical” quantity E from 100 to 230 GPa at l₀ increasing from 10 to 80 mm with a damping behavior has been established. The E(l₀) dependence is shown to be described via the empirical equation that allows the E value to be predicted as a function of l₀. According to the prediction, a saturation of the true value E with a yield to a plateau at E = 242 GPa occurs at l₀ = 200 mm.