FIELD: technology of polymers.
SUBSTANCE: invention relates to technology for preparing fibers, in particular, polypropylene fibers from nonwoven materials from a melt. Fiber is made from propylene polymeric composition (A) showing the melt flow rate value MFR (1) 6-150 g/10 min. The composition is chosen from group comprising the following components: (i) crystalline propylene polymeric composition comprising at least 0.8 wt.-% of ethylene, melting point 155°C or above, xylene-soluble fraction at room temperature, less 10 wt.-%, and the ratio index of polymeric fraction collected at temperature 25-95°C, and xylene-soluble fraction at temperature above 4; and (ii) crystalline propylene polymeric fraction with a boiling point 153°C and above, the content of xylene-soluble fraction at room temperature less 10 wt.-%. Indicated composition comprises at least 0.64 wt.-% of ethylene and/or (C4-C10)-α-olefin structural unit and comprises the following components: (I) 20-80% of crystalline propylene polymer comprising up to 1.5 wt.-% of ethylene and/or (C4-C10)-α-olefin, and (II) 20-80% of crystalline propylene statistic copolymer chosen from group comprising the following components: (IIa) propylene copolymer with 0.8-10 wt.-% of ethylene and/or (IIb) propylene copolymer with 1.5-18 wt.-% of (C4-C10)-α-olefin. Indicated polymeric composition (A) is prepared by chemical degradation of the previous polymer composition (A) showing the melt flow rate values MFR (2) from 0.5 to 50 g/10 min under condition that the melt flow rate ratio MFR (2) = 1.5-60. Prepared fibers are designated for preparing nonwoven materials used as interweaving material and ornamented fabric.
EFFECT: improved preparing method, valuable properties of fibers.
10 cl, 11 tbl, 15 ex
