The wear-resistant polyester mixt. with more reliable processing properties, with a m.pt. of 200-230 degrees C (I) contains (I) a thermoplastic polyester, (B) a thermoplastic polyurethane (PU) and opt. other non-polymeric additives. Also claimed is a process for the prodn. of (I) by combining the components immediately before the extruder inlet and homogenising the mixt. in the entry and mixing sections of the extruder. Also claimed are wear-resistant monofilaments of (I) with an initial modulus of more than 5 N/tex at 25 degrees C, pref. with an ultimate tensile and elongation of 20-30 cN/tex and 50-70%, a dry heat shrinkage of 15-40% at 180 degrees C and a shrinkage on boiling of 3-10%. Also claimed is a process for the prodn. of such filaments, by melting (I) in an extruder, filtering in a spinning pack, melt-spinning at 185-245 (pref. 210-235) degrees C with a draw ratio of (1:2)-(1:4), cooling in a bath, drawing off at a speed greater than the melt injection rate (pref. 5-30 m/min.), post-stretching with a total stretch ratio of (1:4)-(1:8) and then fixing at 160-240 degrees C at constant length or with 10-30% shrinkage. Also claimed is a paper machine screen contg. monofilaments of (I).
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