The invention discloses a preparation method of high-strength
polyethylene fibers, and belongs to the technical field of
polyethylene fiber preparation. The method comprises the following steps: firstly, introducing high-molecular-weight
polyethylene resin into a pretreatment
system, introducing a
solvent into the pretreatment
system for swelling, controlling the swelling temperature and swelling time of the pretreatment
system, controlling the
mass ratio of the
solvent to the high-molecular-weight polyethylene resin, and then separating to obtain swelled high-molecular-weight polyethylene resin; mixing the swelled high-molecular-weight polyethylene resin and the non-swelled low-molecular-weight polyethylene resin according to a
mass ratio to obtain a mixed
raw material; the preparation method comprises the following steps: mixing and plasticizing the obtained mixed
raw material by using double screws, extruding and
spinning by using a single-screw extruder to obtain a polyethylene
fiber to be drafted, and carrying out hot roller drafting to obtain the high-strength polyethylene
fiber. The method has the advantages that solution
viscosity is improved, and melt fluidity is increased; the hot roller is fast in
heat transfer and high in efficiency, and fiber heating is more uniform; the drafting consistency is good, the prepared fibers are more uniform, and the comprehensive
mechanical property is better.