| 摘要 |
The invention relates to a method for producing highly stable polypropylene fibres with a strength in excess of 6 cN/dtex. and an elongation of less than 40 %. To obtain the highest possible fineness of fibre, the fibre strands are first spun at a low melting temperature of less than 250 °C and a relatively low drawing speed of less than 100 m/min, whilst being cooled by a gaseous medium. The fibre strands are then stretched in at least three stretching stages with an overall stretching ratio in excess of 4:1, whereby said fibre strands are partially stretched in the first stretching stage to at least 70 % of their overall stretched state. After the stretching process, the fibre strands are cut to form the polypropylene fibres.
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