Ultra high molecular weight polyethylene multifilament yarns, and process for producing thereof

Abstract

The invention relates to a gel spun, ultrahigh molecular weight polyethylene (UHMWPE) multifilament yarn characterized in that said yarn comprises individual monofilaments having a coefficient of variation of their linear density, hereafter CVintra, of less than 30%, wherein the CVintra of a monofilament was determined from linear density values corresponding to a number of 20 representative lengths randomly extracted by cutting from said monofilament and using Formula 1 wherein χi is the linear density of any one of the representative lengths extracted from the monofilament under investigation and Formula 1A is the averaged linear density over the n=20 measured linear densities of said n=20 representative lengths. The invention also relates to a gel spun UHMWPE multifilament yarn characterized in that the yarn has a coefficient of variation in linear density between the monofilaments comprising said yarn, hereafter CVinter, of less than 50%. The invention also relates to a gel spinning process of producing thereof characterized in that a chamber is present before the spinning plate such that no further partitioning of the UHMWPE solution takes place before said solution being finally partitioned into individual monofilaments by the spinning plate and in which chamber the solution has a residence time τ at a constant throughput of UHMWPE solution of at least 5 sec. The invention also relates to a rope, net, medical cable or a composite comprising the yarns of the invention.

Dependencies are inferred from the claim text.