Patent ID: 8858851

Claim:
A process for producing low-titer, high-strength and high-modulus polyethylene fiber, comprising the following steps: a). dissolving the ultra-high molecular weight polyethylene with Mw of 2.5×10 6 ˜5×10 6 into paraffin oil with a low viscosity of 6.5˜7.5 mm 2 /sto form a spinning solution with a concentration of 3˜15%; b). extruding the spinning solution through a thin spinneret with at least 10 orifices, each orifice having a leading hole and a spinning hole, a diameter Φ of 0.7˜0.8 mm and a length/diameter ratio of the spinning hole of 10˜12, by applying a high pressure in the range of 2.5±1.0 MPa to the spinning solution, such that the fluid in the orifices is extruded at a shear rate of above 200 sec −1 and not above 3 500 sec −1 , wherein the extruding flow rate for a single orifice is 2.5˜5 ml/min; and then performing a jet stretch at a deformation rate of 200˜5 000 min −1 within an air-gap of 10˜15 mm between the spinneret and the quench bath surface; c). feeding the jet-stretched fluid into the quench bath to form gel filaments; d). extracting and drying the gel filaments; and e). performing a multistage ultrahigh post stretch on the dried gel filaments with a stretch ratio of 15 or less.