PROCESS FOR THE PRODUCTION OF POLYMER FILAMENTS HAVING HIGH TENSILE STRENGTH

摘要

PROCESS FOR THE PRODUCTION OF POLYMER FILAMENTS HAVING HIGH TENSILE STRENGTH An improved process for the preparation of polymer filaments having a high tensile strength and modulus by spinning a solution of high-molecular weight polymer and thereafter stretching the filament thus formed. A solution of an ethylene polymer or copolymer, containing at least 80 percent by weight solvent, is spun at a temperature above the gel point of the solution. The ethylene polymer or copolymer contains at most about 5 percent by weight of an alkene having 3 to 8 carbon atoms, has a weight-average molecular weight Mw higher than 4 x 105 kg/kmole, and has a weight/number average molecular weight ratio Mw/Mn lower than 5. The spun polymer solution, is thereafter cooled to a temperature below its gel point to form a gel filament, which gel filament is thereafter strenght to form a polymer filament having a tensile strength of at least about 1.5 GPa at room temperature.