Method of delaying and reducing texture reversion of a textured artificial turf yarn

Patent metadata

Field	Value
Publication number	US-11655566-B2
Application number	US-201816651689-A
Country	US
Kind code	B2
Filing date	Oct 5, 2018
Priority date	Oct 6, 2017
Publication date	May 23, 2023
Grant date	May 23, 2023

Abstract

The invention provides for a method of delaying and reducing texture reversion of a textured artificial turf yarn (145), characterized by using a stretched and textured monofilament yarn as the textured artificial turf yarn, the stretched and textured monofilament yarn comprising a polymer mixture (400, 500), wherein the polymer mixture is at least a three-phase system, wherein the polymer mixture comprises a first polymer (402), a second polymer (404), and a compatibilizer (406), wherein the first polymer and the second polymer are immiscible, wherein the first polymer forms polymer beads (408) surrounded by the compatibilizer within the second polymer.

First claim

The invention claimed is:

1. A method of delaying and reducing texture reversion of a textured artificial turf yarn, the method comprising:
providing a monofilament yarn comprising a polymer mixture, wherein the polymer mixture is at least a three-phase system, wherein the polymer mixture comprises a first polymer, a second polymer, and a compatibilizer, wherein the first polymer and the second polymer are immiscible, wherein the first polymer forms polymer beads surrounded by the compatibilizer within the second polymer;
stretching the monofilament yarn to elongate the polymer beads to increase a volume of a crystalline fraction in the polymer mixture, and to form the monofilament yarn into a stretched monofilament yarn; and
texturing the stretched monofilament yarn to form the textured and stretched monofilament yarn,
wherein the elongating of the polymer beads and the increasing of the volume of a crystalline fraction delay and reduce the texture reversion of the textured artificial yarn, and wherein
the method further comprising:
receiving differential scanning calorimetry, DSC, data of a sample of the polymer mixture;
determining one or more melting temperatures of the monofilament yarn using the DSC data; and
determining a desired temperature of a gas-dynamic texturing process using the one or more melting temperatures,
wherein the texturing of the stretched monofilament yarn to form the textured and stretched monofilament yarn is performed in a gas-dynamic texturing process using a texturing apparatus and a controller being programmed to hold an actual temperature of the gas-dynamic texturing process in the texturing apparatus at the desired temperature.

2. The method of claim 1 , wherein the stretched and textured monofilament yarn is integrated into an artificial turf backing to form an artificial turf.

3. The method of claim 2 , wherein the stretched and textured monofilament yarn integrated into the artificial turf backing is subjected to a mechanical and/or weathering stress.

4. The method of claim 1 , wherein the first polymer comprises polyamide and the second polymer comprises polyethylene, or the first polymer comprises polyester and the second polymer comprises polyethylene, or the first polymer comprises polyester and the second polymer comprises polypropylene, or the first polymer comprises polyamide and the second polymer comprises polypropylene, or wherein the first polymer is one type of polyethylene and the second polymer is another type of polyethylene.

5. The method of claim 1 , the compatiblizer comprises any one of the following: a maleic acid grafted on polyethylene or polyamide; a maleic anhydride grafted on free radical initiated graft copolymer of polyethylene, SEBS, EVA, EPD, or polyproplene with an unsaturated acid or its anhydride such as maleic acid, glycidyl methacrylate, ricinoloxazoline maleinate; a graft copolymer of SEBS with glycidyl methacrylate, a graft copolymer of EVA with mercaptoacetic acid and maleic anhydride; a graft copolymer of EPDM with maleic anhydride; a graft copolymer of polypropylene with maleic anhydride; a polyolefin-graft-polyamidepolyethylene or polyamide; and a polyacrylic acid type compatibalizer.

6. The method of claim 1 , the method comprising the steps of:
forming a first mixture by mixing the first polymer with the compatibilizer;
heating the first mixture;
extruding the first mixture;
granulating the extruded first mixture;
mixing the granulated first mixture with the second polymer; and
heating the granulated first mixture with the second polymer to form the polymer mixture.

7. The method of claim 1 , wherein the polymer mixture is at least a four phase system, wherein the polymer mixture comprises at least a third polymer, wherein the third polymer is immiscible with the second polymer, wherein the third polymer further forms the polymer beads surrounded by the compatibilizer within the second polymer.

8. The method of claim 7 , the method comprising the steps of:
forming a first mixture by mixing the first polymer and the third polymer with the compatibilizer;
heating the first mixture;
extruding the first mixture;
granulating the extruded first mixture;
mixing the first mixture with the second polymer; and
heating the mixed first mixture with the second polymer to form the polymer mixture.

9. The method of claim 7 , wherein the third polymer is any one of the following: polyethylene terephthalate (PET) and polybutylene terephthalate (PBT).

10. The method of claim 1 , wherein the polymer mixture further comprises any one of the following: a wax, a dulling agent, a UV stabilizer, a flame retardant, an anti-oxidant, a pigment, and combinations thereof.

11. The method of claim 1 , the method comprising the steps of:
extruding the polymer mixture into a monofilament yarn;
quenching the monofilament yarn; and
heating the quenched monofilament yarn,
wherein the heated monofilament yarn is stretched in the stretching of the monofilament yarn.

12. The method of claim 6 , wherein the polymer bead comprises crystalline portions and amorphous portions, wherein elongating the polymer beads causes an increase in the size of the crystalline portions relative to the amorphous portions.

13. The method of claim 1 , wherein the sample is taken from the polymer mixture or the stretched monofilament yarn.

14. The method of claim 1 , wherein the desired temperature of the gas-dynamic texturing process is determined such that a portion of a crystalline fraction of the polymer mixture is in a solid state in the gas-dynamic texturing process and another portion of the crystalline fraction of the polymer mixture is in a molten state in the gas-dynamic texturing process.

15. The method of claim 1 , wherein the one or more melting temperatures is two or more melting temperatures, wherein the desired temperature is determined within a temperature range or the desired temperature is determined as a range within the temperature range, wherein the temperature range has an upper boundary temperature being less or equal to one of the melting temperatures, wherein the temperature range has a lower boundary temperature being greater or equal to another one of the melting temperatures.

16. The method of claim 1 , wherein each of the one or more melting temperatures is a melting temperature of the respective polymer of the polymer mixture.

17. The method of claim 1 , wherein the DSC data comprises a curve of a heat flow versus temperature in a temperature range, wherein the curve has a base line, wherein the curve coincides with the base line at a lower boundary temperature of the temperature range and at an upper boundary temperature of the temperature range, wherein the upper boundary temperature and the lower boundary temperature are different temperatures, wherein the desired temperature complies with the following constraint: a ratio of an integral value and an overall integral value is within a predefined range, wherein the integral value is equal to an integral of a difference of the curve and the base line from the lower boundary temperature to the desired temperature, wherein the overall integral value is equal to an integral of the difference of the curve and the base line from the lower boundary temperature to the upper boundary temperature.

18. The method of claim 17 , wherein the predefined range is 0.05-0.15.

19. The method of claim 1 , wherein the texturing apparatus comprises an inlet for a fluid under pressure for gas-dynamic texturing of the stretched monofil

Assignees

• Polytex Sportbelage Produktions Gmbh

Inventors

• Sick Stephan
• Sander Dirk
• Jansen Bernd
• Lohr Ivo
• Brown Kris

Classifications

• D01F1/106

  Radiation shielding agents, e.g. absorbing, reflecting agents · CPC title

• D10B2505/202

  Artificial grass · CPC title

• E01C13/08

  Surfaces simulating grass {; Grass-grown sports grounds (grass-like surfaces for skiing E01C13/12)} · CPC title

• D02G1/12

  using stuffer boxes · CPC title

• D01F8/08

  with at least one polyacrylonitrile as constituent · CPC title