Artificial turf suitable for sports fields

Abstract

The present invention relates to an artificial turf suitable for sports fields consisting at least of a substrate to which first artificial grass fibres are attached and of a granular infill, which is provided between said first artificial grass fibres, wherein said granular infill is made of a foam material comprising polylactic acid or a derivative thereof.

Claims

1. An artificial turf suitable for sports fields comprising a substrate to which first artificial grass fibers are attached and a granular infill between said first artificial grass fibers, wherein said granular infill comprises a biobased and/or biodegradable foam material selected from the group consisting of polylactic acid (PLA), polybutylene succinate (PBS), polycaprolactone (PCL), poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), polyhydroxyalkanoate (PHA) and polyhydroxybutyrate (PHB), polyethylene (PE), polypropylene (PP), or a derivative thereof, and wherein the outer surface of said granular infill has undergone a roughened treatment.

2. An artificial turf according to claim 1, wherein said granular infill further comprises one or more oil-based polymers selected from the group consisting of foamed polyethylene terephthalate(PET), polyethylene foam (PEF), polyethylene (PE), LDPE, HDPE, LLDPE, polystyrene (PS) and poly(vinyl chloride) (PVC).

3. An artificial turf according to claim 1, wherein said granular infill further comprises one or more fossil-based polymers selected from the group consisting of copolyester of butanediol, adipic acid and terephtalic acid (PBAT), poly(methyl methacrylate), polystyrene and polyolefins.

4. An artificial turf according to claim 1, wherein said granular infill further comprises one or more materials chosen from the group of starch, natural fillers, wherein the natural fillers are selected from cork, coconut, hemp, grass, cellulose, reed, hay, straw and cardboard.

5. An artificial turf according to claim 1, wherein said granular infill further comprises one or more mineral fillers chosen from the group of zeolites, calcium carbonate, silicon dioxide, aluminum oxide, magnesium oxide, chalk, kaolin and talc.

6. An artificial turf according to claim 1, wherein said granular infill further comprises one or more additives chosen from the group of antistatic additives, hydrophilic additive, algaecide and pigments.

7. An artificial turf according to claim 1, wherein the granular infill is provided in a density of 60-500 kg/m.sup.3.

8. An artificial turf according to claim 7, wherein the granular infill is provided in a density of 60-300 kg/m.sup.3.

9. An artificial turf according to claim 7, wherein the granular infill is provided in a density of 80-150 kg/m.sup.3.

10. An artificial turf according to claim 7, wherein the granular infill is provided in a density of 120-140 kg/m.sup.3.

11. An artificial turf according to claim 1, wherein the shape of said foam material is round, oblong or cylindrical with an aspect ratio of L/D of 3 and higher.

12. An artificial turf according to claim 1, wherein said granular infill has a diameter in a range of 0.5-5 mm.

13. An artificial turf according to claim 12, wherein said granular infill has a diameter in a range of 2-3 mm.

14. An artificial turf according to claim 1, wherein the shape of said granular infill is chosen from the group of coffee bean, cylindrical or oblong.

15. An artificial turf according to claim 14, characterized in that the shape of said granular infill is coffee bean.

16. An artificial turf according to claim 1, wherein the outer surface of said granular infill is provided with a coating.

17. An artificial turf suitable for sports fields comprising a substrate to which first artificial grass fibers are attached and of a granular infill, which is provided between said first artificial grass fibers, wherein said granular infill is made of a biobased and/or biodegradable foam material, wherein the biobased and/or biodegradable foam material is selected from the group consisting of polylactic acid (PLA), polybutylene succinate (PBS), polycaprolactone (PCL), poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), polyhydroxyalkanoate (PHA) and polyhydroxybutyrate (PHB), polyethylene (PE), polypropylene (PP), or a derivative thereof, wherein the outer surface of said granular infill has undergone a roughened treatment.

Description

EXAMPLE 1

(1) Polylactic (PLA) microbeads have been prepared on a Berstorff ZE75A_UTX x 36D twin-screw extruder equipped with a Gala underwater granulator (A6). The PLA used was Synterra BF1505 prepared by Synbra Technology. The PLA microbeads have been impregnated in a pressure vessel at 13 bar CO.sub.2 for 18 hours to absorb blowing agent. Pre-foaming of the impregnated microbeads has been done on a commercial EPS prefoamer using a mixture of steam and air to obtain an average pre-foaming temperature of 95° C. The pre-foaming time was 40 sec, which was sufficient to obtain a density of 60 g/L and the right surface modification. After pre-foaming the foamed beads have been coated with 0.5% of a 35% solids content active food grade silicone emulsion (marketed by Van Meeuwen as Food care (trademark) Antiblock).

EXAMPLE 2

(2) PLA microbeads have been prepared on a Berstorff ZE75A_UTX x 36D twin-screw extruder equipped with a Gala underwater granulator (A6). The PLA used was Synterra BF1505 prepared by Synbra Technology. The PLA microbeads have been impregnated in a pressure vessel at 10 bar CO.sub.2 for 18 hours to absorb blowing agent. Pre-foaming of the impregnated microbeads has been done on a commercial EPS prefoamer using a mixture of steam and air to obtain an average pre-foaming temperature of 95° C. The pre-foaming time was 40 sec, which was sufficient to obtain a density of 140 g/L and the right surface modification. After pre-foaming the foamed beads have been coated with 0.5% of 35% solids content active food grade silicone emulsion (marketed by Van Meeuwen as Foodcare (trademark) Antiblock).

EXAMPLE

(3) A commercial available artificial turf was provided with the foam material as manufactured according to Example 1 and 2.

(4) The granular infill manufactured according to Example 1 and Example 2 is provided between the synthetic fibers of the artificial turf. The artificial turf as used in Example 3 includes a pile fabric having a backing and pile elements extending upwardly from the backing, and an infill layer filled on the backing such that the pile elements are at least partially embedded in the infill layer composed of the foam material as manufactured according to Example 1 and 2.

(5) The artificial turf having the foam material as manufactured according to Example 1 and 2 as infill has acceptable elasticity, hardness, and sliding resistance, so that it is possible to prevent the players from being injured and improve playability.

(6) The value for Rotational resistance should be high, i.e. at least 20.

(7) Table 1 discloses experimental results for different types of granular infill, such as polypropylene (PP), recycled polyethylene terephthalate (rPET), polyethylene (PE), polystyrene (PS) and polylactic acid (PLA).

(8) TABLE-US-00001 TABLE 1 experimental results for different types of granular infill extruder % addition Rotational polymer type recipe speed kg/hr technique blowing agent shape blowing agent density resistance PP 20/50/30 blend of 1 in/line isobutane spherical 3% 240 23 PP531PH/WB135HMS/ foaming LDPE 2202U0 rPET rPET: recycled PET 1 in/line cyclopentane spherical 4% 300 27 flakes PET bottle foaming grade rPET rPET: recycled PET 1 in/line cyclopentane coffeebean 4% 450 35 flakes PET bottle foaming grade PP 25/45/30 blends of 1 in/line isobutane spherical 7% 30 nd linear foaming PP531PH/WB135HMS/ LDPE 2202U0 PE LDPE 2202U0 1 in/line isobutane cillinder 3% 330 20 foaming LD/3 PS Styrex EPS 1012RC 1 in/line pentane spherical 5.6%.sup.  60 nd foaming PLA BF2004 plus 1% talc 5 in/line CO2 spherical 7% 600 26 foaming PLA BF2004 + 20% Ecovio 5 in/line CO2 coffeebean 6% 500 28 C2332 + 1.5% talc foaming PLA BF2004 + 20% 5 in/line pentane spherical 4% 300 31 Ecoflex + 1.5% talc foaming polymer type recipe PP 20/50/30 blend of PP531PH/WB135HMS/LDPE 2202U0 rPET rPET: recycled PET flakes PET bottle grade rPET rPET: recycled PET flakes PET bottle grade PP 25/45/30 blends of linear PP531PH/WB135HMS/LDPE 2202U0 PE LDPE 2202U0 PS Styrex EPS 1012RC PLA BF2004 plus 1% talc PLA BF2004 + 20% Ecovio C2332 + 1.5% talc PLA BF2004 + 20% Ecoflex + 1.5% talc BASF Ecovio C2332 is a mixture of 82% PBAT and 18% PLA Sabic ® PP 531Ph (homopolymer, 3 g/10 min @ 230° C., 2.16 kg); Sabic ® PP 620P (random copolymer, 17 g/10 min); Borealis PP WB135HMS (homopolymer, 2.4 g/10 min); Borealis PP WB260HMS (random copolymer, 2.4 g/10 min); Borealis PP HB600TF (homopolymer, 2 g/10 min, Tm = 162-166° C.). SABIC ® LDPE 2202U0 (high melt strength) Styrex EPS 1012RC Synbra technology Synterra BF2004 Synbra Technology n.a not applicable nd not determined