Patent ID: 11859316
Assignee: TOTALENERGIES ONETECH BELGIUM
Field: Textile and paper machines (Mechanical engineering)
Classification: CPC D  C  Y | IPC C  D

Claim 0:
1. A process for the production of fibers comprising:
(a) polymerizing propylene and at least one comonomer in presence of a metallocene-based polymerization catalyst, to obtain a metallocene random copolymer of propylene and at least one comonomer;
(b) melt-extruding a polypropylene composition comprising the metallocene random copolymer obtained in step (a) to obtain a molten polypropylene stream;
(c) extruding the molten polypropylene stream of step (b) from capillaries of a spinneret, thus obtaining filaments of molten polypropylene; and
(d) subsequently rapidly reducing a diameter of the filaments to obtain a final diameter;
wherein said metallocene random copolymer has a comonomer content of from 1.2 wt % to 1.8 wt %, relative to a total weight of said metallocene random copolymer;
wherein the at least one comonomer is ethylene; and
wherein said metallocene random copolymer has a molecular weight distribution, defined as Mw/Mn and determined by gel permeation chromatography, of from 1.0 to 3.0, obtained without thermal or chemical degradation; a melt flow index of at least 25 dg/min and at most 50 dg/min, determined according to ISO 1133, condition L, at 230° C. and 2.16 kg; and a melting temperature Tmelt, determined by Differential Scanning Calorimetry according to ISO 3146, of at most 140° C.