Effect of zone-drawing conditions on the tensile properties of gel-spun ultrahigh molecular weight polyethylene fiber

Ultrahigh molecular weight polyethylene (PE) solution of concentration of 5 wt% was quenched to room temperature to form gel and spun to form fiber, and the effects of zone-drawing conditions on the tensile properties were investigated. Breaking stress and tensile modulus of drawn gel-spun fiber increased and breaking strain decreased with decreasing heat band speed and with increasing drawing temperature. On the other hand, there was a optimum drawing stress for the maximum draw ratio. Maximum draw ratio up to 26.4 was achieved at the heat band speed, drawing temperature, and drawing stress of 1 mm/min, 128 °C, and 20 MPa, respectively. Breaking stress, tensile modulus, and breaking strain of gel-spun fiber drawn at these conditions were 2.63 GPa, 43.3 GPa, and 12.75%, respectively. It was identified that breaking stress and tensile modulus increased with an increase in the draw ratio and fraction of tie molecules. Fraction of tie molecules in this study was 0.1732. This value was about 26% of maximum fraction of tie molecules obtained by the drawing of PE.