Agricultural film comprising a copolyamide of a diamine, a dimer acid and a lactam

Abstract

The present invention relates to an agricultural film (AF) comprising at least one copolyamide, wherein the copolyamide has been prepared by polymerizing at least one lactam and a monomer mixture (M). The present invention further relates to a process for producing the agricultural film (AF) and to the use of the agricultural film (AF) as mulch film, as silage film, as greenhouse film or as silo film.

Claims

1. An agricultural film comprising: at least one copolyamide prepared by polymerizing the following components: (A) 60% to 80% by weight of at least one lactam, and (B) 20% to 40% by weight of a monomer mixture (M) comprising the following components: (B1) at least one C.sub.32-C.sub.40 dimer acid, and (B2) at least one C.sub.4-C.sub.12 diamine, wherein: percentages by weight of components (A) and (B) are each based on the sum total of the percentages by weight of components (A) and (B); and the copolyamide has a viscosity number of from 212 to 280 ml/g, determined in a 0.5% by weight solution of the copolyamide in a mixture of phenol/o-dichlorobenzene in a weight ratio of 1:1.

2. The agricultural film according to claim 1, wherein component (A) is selected from the group consisting of 3-aminopropanolactam, 4-aminobutanolactam, 5-aminopentanolactam, 6-aminohexanolactam, 7-aminoheptanolactam, 8-aminooctanolactam, 9-aminononanolactam, 10-aminodecanolactam, 11-aminoundecanolactam, and 12-aminododecanolactam.

3. The agricultural film according to claim 1, wherein component (B) comprises: from 45 to 55 mol % of component (B1), and from 45 to 55 mol % of component (B2), based in each case on the total molar amount of component (B).

4. The agricultural film according to claim 1, wherein component (B2) is selected from the group consisting of tetramethylenediamine, pentamethylenediamine, hexamethylenediamine, decamethylenediamine, and dodecamethylenediamine.

5. The agricultural film according to claim 1, wherein component (B1) is prepared proceeding from at least one unsaturated fatty acid selected from the group consisting of an unsaturated C.sub.16 fatty acid, an unsaturated C.sub.18 fatty acid and an unsaturated C.sub.20 fatty acid.

6. The agricultural film according to claim 1, wherein the copolyamide has a glass transition temperature of from 20 to 50° C.

7. The agricultural film according to claim 1, wherein the copolyamide has a melting temperature of from 150 to 215° C.

8. The agricultural film according to claim 1, wherein the agricultural film comprises at least one first layer comprising the at least one copolyamide, and at least one additional layer, wherein the at least one additional layer comprises at least one-further polymer (FP) selected from the group consisting of a polyolefin, a poly(ethylene-vinyl alcohol), a poly(ethylene-vinyl acetate), a polyethylene terephthalate, a polyvinylidene chloride, and a maleic anhydride-grafted polyolefin.

9. The agricultural film according to claim 1, wherein the agricultural film is produced in a casting process or in a blowing process.

10. He agricultural film according to claim 1, wherein the agricultural film has a thickness of from 0.1 μm to 1 mm.

11. The agricultural film according to claim 1, wherein the copolyamide is a random copolymer.

12. The agricultural film according to claim 1, wherein the agricultural film is selected from the group consisting of a silage film, a mulch film and a greenhouse film.

13. A process for producing the agricultural film according to claim 1, comprising: i) providing at least one copolyamide prepared by polymerizing the following components: (A) 60% to 80% by weight of at least one lactam, (B) 20% to 40% by weight of a monomer mixture (M) comprising the following components: (B1) at least one C.sub.32-C.sub.40 dimer acid and (B2) at least one C.sub.4-C.sub.12 diamine, where the percentages by weight of components (A) and (B) are each based on the sum total of the percentages by weight of components (A) and (B), in molten form in a first extruder, ii) extruding the at least one copolyamide in molten form provided in step i) out of the first extruder through a die to obtain a film of the at least one copolyamide in molten form, iii) cooling the film obtained in step ii) with solidification of the at least one copolyamide to obtain the agricultural film.

14. A film comprising the agricultural film according to claim 1.

15. A film comprising the agricultural film according to claim 1, wherein the film is a silage film, a mulch film, a greenhouse film or a silo film.

16. The agricultural film according to claim 1, wherein: the monomer mixture (M) optionally further comprises (B3) at least one C.sub.4-C.sub.20 diacid; and the copolyamide is free from monomer units other than those from components (A), (B1), (B2), and (B3).

Description

EXAMPLES

(1) The properties of the agricultural films (AF) were determined as follows:

(2) The viscosity number of copolyamides comprising units derived from a C.sub.32-C.sub.40 dimer acid was determined in a 0.5% by weight solution of phenol/o-dichlorobenzene in a weight ratio of 1:1 at 25° C.

(3) The viscosity number of copolyamides and polyimides that do not comprise any units derived from a C.sub.32-C.sub.40 dimer acid was determined in a 0.5% by weight solution in 96% by weight sulfuric acid at 25° C. according to EN ISO 307: 2007+Amd 1: 2013.

(4) The glass transition temperatures and melting temperatures were determined according to ISO 11357-1: 2009, ISO 11357-2: 2013 and ISO 11357-3: 2011. For this purpose, two heating runs were conducted and the glass transition and melting temperatures were ascertained from the second heating run.

(5) The densities of the polyamides were determined by the gas pycnometer method according to EN ISO 1183-3: 1999.

(6) For determination of the proportion of polyamide-6,36 in the copolyamide, the copolyamide was hydrolyzed in dilute hydrochloric acid (20%). This protonates the units derived from hexamethylenediamine, with the chloride ion from the hydrochloric acid forming the counterion.

(7) By means of ion exchanger, this chloride ion was then exchanged for a hydroxide ion with release of hexamethylenediamine. By titration with 0.1 molar hydrochloric acid, the hexamethylenediamine concentration is then determined, from which the proportion of polyamide-6,36 in the copolyamide can be determined.

(8) Tear propagation resistance is determined according to Elmendorf, DIN ISO 6383-2: 2004 in extrusion direction (MD) and at right angles thereto (TD). The films were conditioned under standard climatic conditions for non-tropical countries according to DIN EN ISO 291: 2008.

(9) Modulus of elasticity is determined according to ISO 527-3: 1995.

(10) The impact resistance of the monofilms was determined according to DIN ISO 7765-2: 1994 with 5 specimens at a relative air humidity of 50% (50% AH), with reporting of the puncture energy in the present context.

(11) The impact resistance of the multilayer films was determined according to DIN ISO 7765-2: 1994 with 5 specimens at a relative air humidity of 0% (0% AH), with reporting of the puncture energy in the present context.

(12) The acid stability of monofilms was determined in sulfuric acid. For this purpose, monofilms were mounted in polypropylene slide frames and immersed in sulfuric acid, and a check was made after 24 h as to whether the monofilm is still intact. Depending on the production process for the monofilms, a different concentration of sulfuric acid was used. Monofilms produced by a casting process were placed into 30% sulfuric acid; monofilms produced by a blowing process were placed into 25% sulfuric acid. In the tables which follow, in connection with acid stability, “0” means that the monofilm is still intact after immersion in sulfuric acid for 24 h; “X” means that the monofilm has dissolved.

(13) The following polymers were used:

(14) Polyamides

(15) P-1 nylon-6 from BASF SE®, sold under the Ultramid B40L brand name, with a viscosity number of 250 mL/g, a glass transition temperature of 57° C., a melting temperature of 220° C. and a density of 1.153 g/mL. P-2 nylon-6 from BASF SE®, sold under the Ultramid B33L brand name, with a viscosity number of 195 mL/g, a glass transition temperature of 56° C., a melting temperature of 220° C. and a density of 1.145 g/mL. P-3 copolymer of nylon-6 and nylon-6,6 (PA 6/6.6) from BASF SE®, sold under the Ultramid C40L brand name, with a viscosity number of 250 mL/g, a glass transition temperature of 53° C., a melting temperature of 190° C. and a density of 1.143 g/mL. P-4 copolymer of nylon-6 and nylon-6,6 (PA 6/6.6) from BASF SE®, sold under the Ultramid C33L brand name, with a viscosity number of 195 mL/g, a glass transition temperature of 55° C., a melting temperature of 196° C. and a density of 1.144 g/mL.
Copolyamides with Dimer Acid: C-1 A copolyamide of nylon-6 and polyamide-6,36, prepared by the following method: 900 kg of caprolactam (component (A)), 83.5 kg of Pripol 1009 from Croda (C.sub.36 dimer acid, hydrogenated, component (B1)), 19.9 kg of 85% by weight hexamethylenediamine solution (component (B2)) in water, 100 g of Polyapp 2557-CTW antifoam reagent composed of polymethylsiloxane from Polystell do Brazil and 100 kg of water were mixed in a 1930 L tank and blanketed with nitrogen. The outside temperature of the tank was heated to 290° C. and the mixture present in the tank was stirred at this temperature for 11 hours. In the first 7 h the mixture was stirred at elevated pressure, in the next 4 hours under reduced pressure, during which the water formed was distilled off. The copolyamide thus obtained was then discharged from the tank, extruded and pelletized. After the pellets of the copolyamide obtained had been extracted with water at 95° C. for 4×6 hours, the copolyamide was dried at 90 to 140° C. in a nitrogen stream for 10 hours. The viscosity number was 246 mL/g, the glass transition temperature was 49° C. and the melting temperature was 211° C. The proportion of polyamide-6,36 in the copolyamide, based on the total weight of the copolyamide, was 10.5% by weight; the density was 1.116 g/mL. C-2 A copolyamide of nylon-6 and polyamide-6,36, prepared by the following method: 1039 kg of caprolactam (component (A)), 216 kg of Pripol 1009 from Croda (C.sub.36 dimer acid, hydrogenated, component (B1)), 51.7 kg of 85% by weight hexamethylenediamine solution (component (B2)) in water, 100 g of Polyapp 2557-CTW antifoam reagent from Polystell do Brazil and 142 kg of water were mixed in a 1930 L tank and blanketed with nitrogen. The outside temperature of the tank was heated to 290° C. and the mixture was stirred at this temperature for 11 hours. In the first 7 h the mixture was stirred at elevated pressure, in the next 4 hours under reduced pressure, during which the water formed was distilled off. The copolyamide obtained was discharged from the tank, extruded and pelletized. The pellets of the copolyamide obtained were extracted with water at 95° C. for 4×6 hours and then dried at 90 to 140° C. in a nitrogen stream for 10 hours. The copolyamide obtained had a viscosity number of 244 mL/g, a glass transition temperature of 44° C. and a melting temperature of 203° C. The proportion of polyamide-6,36 in the copolyamide, based on the total weight of the copolyamide, was 20.8% by weight; the density was 1.095 g/mL. C-3 A copolyamide of nylon-6 and polyamide-6,36, prepared by the following method: 932 kg of caprolactam (component (A)), 323.2 kg of Pripol 1009 from Croda (C.sub.36 dimer acid, hydrogenated, component (B1)), 77.84 kg of 85% by weight hexamethylenediamine solution (component (B2)) in water and 153 kg of water were mixed in a 1930 L tank and blanketed with nitrogen. The outside temperature of the tank was heated to 290° C. and the mixture was stirred at this temperature for 11 hours. In the first 7 h the mixture was stirred at elevated pressure, in the next 4 hours under reduced pressure, during which water formed was distilled off. The copolyamide obtained was discharged from the tank, extruded and pelletized. The pellets of the copolyamide obtained were extracted with water at 95° C. for 4×6 hours and then dried at 90 to 140° C. in a nitrogen stream for 10 hours. The copolyamide obtained had a viscosity number of 259 mL/g, a glass transition temperature of 38° C. and a melting temperature of 188° C. The proportion of polyamide-6,36 in the copolyamide, based on the total weight of the copolyamide, was 30.3% by weight; the density was 1.076 g/mL. C-4 A copolyamide of nylon-6 and polyamide-6,36, prepared by the following method: 932 kg of caprolactam (component (A)), 322 kg of Empol 1061 from BASF SE (C.sub.36 dimer acid, unhydrogenated, component (B1)), 77.84 kg of 85% by weight hexamethylenediamine solution (component (B2)) in water and 153 kg of water were mixed in a 1930 L tank and blanketed with nitrogen. The outside temperature of the tank was heated to 290° C. and the mixture was stirred at this temperature for 11 hours. In the first 7 h the mixture was stirred at elevated pressure, in the next 4 hours under reduced pressure, during which water formed was distilled off. The copolyamide obtained was discharged from the tank, extruded and pelletized. The pellets of the copolyamide obtained were extracted with water at 95° C. for 4×6 hours and then dried at 90 to 140° C. in a nitrogen stream for 10 hours. The copolyamide obtained had a viscosity number of 212 mL/g, a glass transition temperature of 38° C. and a melting temperature of 187° C. The proportion of polyamide-6,36 in the copolyamide, based on the total weight of the copolyamide, was 28.9% by weight; the density was 1.076 g/mL.
Further Polymer (FP) FP-1 Low-density polyethylene (LDPE) from LyondellBasell®, sold under the Lupolen 2420 F brand name with an MFR (melt flow rate) (190° C./2.16 kg) of 0.75 g/10 min. FP-2 Low-density polyethylene (LDPE) from LyondellBasell®, sold under the Lupolen 3020 K brand name with an MFR (melt flow rate) (190° C./2.16 kg) of 4 g/10 min. FP-3 Anhydride-modified linear low-density polyethylene (LLDPE) from DuPont®, sold under the Bynel 4104 brand name with an MFR (melt flow rate) (190° C./2.16 kg) of 1.1 g/10 min. FP-4 Anhydride-modified linear low-density polyethylene (LLDPE) from DuPont®, sold under the Bynel 4105 brand name with an MFR (melt flow rate) (190° C./2.16 kg) of 4 g/10 min. FP-5 A poly(ethyl-vinyl alcohol) (EVOH) from Kuraray®, sold under the EVAL F171B brand name with an MFR (melt flow rate) (210° C./2.16 kg) of 1.8 g/10 min and an ethylene content of 32 mol %. FP-6 A poly(ethyl-vinyl alcohol) (EVOH) from Kuraray®, sold under the EVAL L171B brand name with an MFR (melt flow rate) (210° C./2.16 kg) of 4 g/10 min and an ethylene content of 27 mol %.
Production of Monofilms by a Casting Process

(16) For production of monofilms, a 7-layer cast film system from Collin® with a die head width of 800 mm was used. Thus, 7 extruders were used. 6 of the extruders had a diameter of 30 mm (extruders B, C, D, E, F, G); one extruder had a diameter of 45 mm (extruder A). Each of the 7 extruders were loaded with the same component. The melt from extruder A was in contact with the casting roll; the melt from extruder G was the furthest removed therefrom. The sequence of the layers was A, B, C, D, E, F, G. The films produced had a thickness of 100 μm and the layers had a layer thickness of 15/14/14/14/14/14/15 μm. The components used and the results of the measurement of the tear propagation resistance, modulus of elasticity and puncture resistance are specified in table 1. The percentages by weight of component (B) specified in table 1 are understood to mean the percentages by weight of units derived from component (B) (polyamide-6,36 units) in the copolyamide, based on the total weight of the copolyamide.

(17) TABLE-US-00001 TABLE 1 V1 V2 V3 B4 B5 B6 Component P-2 P-4 FP-1 C-1 C-2 C-3 Component (B) [% by wt.] — — — 10.5 20.8 30.3 Tear [mN] 2337 2601 3704 3076 6329 7706 propagation (8N (8N (8N (8N (32N (32N resistance (MD) pendulum) pendulum) pendulum) pendulum) pendulum) pendulum) Tear [mN] 2046 3337 6424 2734 6087 7588 propagation (8N (8N (8N (8N (8N (8N resistance (TD) pendulum) pendulum) pendulum) pendulum) pendulum) pendulum) Puncture energy [J] 5.5 3.9 0.5 5.6 5.6 6.5 (50% AH) Modulus of [MPa] 758 439 166 713 621 514 elasticity (MD) Modulus of [MPa] 756 469 167 684 621 365 elasticity (TD) Stability in 30% 0 X 0 0 0 sulfuric acid
Production of Multilayer Films by a Casting Process

(18) Multilayer films comprising three different polymers were produced in the above-described 7-layer cast film system from Collin®. The multilayer films obtained had a thickness of 100 μm and the layers had a layer thickness of 15/14/14/14/14/14/15 μm. The extruders of the cast film system were charged with the components in accordance with the makeup of the multilayer films specified in table 2. The percentages by weight of component (B) specified in table 2 are understood to mean the percentages by weight of units derived from component (B) (polyamide-6,36 units) in the copolyamide, based on the total weight of the copolyamide. Table 2 also states the properties of the multilayer film produced.

(19) TABLE-US-00002 TABLE 2 V7 V8 B9 B10 B11 Makeup FP-2 // FP-4 // FP-2 // FP-4 // FP-2 // FP-4 // FP-2 // FP-4 // FP-2 // FP-4 // P-2 // P-2 // P-2 // P-4 // P-4 II P-4 // C-1 // C-1 // C-1 // C-2 // C-2 // C-2 // C-3 // C-3 // C-3 // FP-4 // FP-2 FP-4 // FP-2 FP-4 // FP-2 FP-4 // FP-2 FP-4 // FP-2 Component (B) [% by wt.] — — 10.5 20.8 30.3 Tear [mN] 1293 1850 1702 2841 5874 propagation (8N pendulum) (8N pendulum) (8N pendulum) (8N pendulum) (8N pendulum) resistance (MD) Tear [mN] 1438 1998 2131 3709 15856 propagation (8N pendulum) (8N pendulum) (8N pendulum) (8N pendulum) (32N pendulum) resistance (TD) Puncture energy [J] 0.3 0.3 0.3 1.4 3.1 (0% AH) Modulus of [MPa] 437 347 431 408 353 elasticity (MD) Modulus of [MPa] 432 344 442 403 328 elasticity (TD)
Production of Multilayer Films by a Casting Process

(20) Multilayer films comprising five different polymers were produced in the above-described 7-layer cast film system from Collin®. The multilayer films obtained had a thickness of 100 μm and the layers had a layer thickness of 15/14/14/14/14/14/15 μm. The extruders of the cast film system were charged with the components in accordance with the makeup of the multilayer films specified in table 3. The percentages by weight of component (B) specified in table 3 are understood to mean the percentages by weight of units derived from component (B) (polyamide-6,36 units) in the copolyamide, based on the total weight of the copolyamide. Table 3 also states the properties of the multilayer film produced.

(21) TABLE-US-00003 TABLE 3 V12 V13 B14 B15 B16 Makeup FP-2 II FP-4 // FP-2 // FP-4 // FP-2 // FP-4 // FP-2 // FP-4 // FP-2 // FP4 // P-2 // FP-6 // P-2 P-4 // FP-6 // P-4 // C-1 // FP-6 // C-1 // C-2 // FP-6 // C-2 // C-3 // FP-6 // C-3 // // FP-4 // FP-2 FF-4 // FP-2 FP-4 // FP-2 FP4 // FP-2 FP-4 // FP-2 Component (B) [% by wt.] — — 10.5 20.8 30.3 Tear propagation [mN] 3649 4344 4257 13206 11311 resistance (MD) (8N pendulum) (8N pendulum) (8Npendulum) (32N pendulum) (32N pendulum) Tear propagation [mN] 3909 8812 6667 17953 14408 resistance (TD) (8N pendulum) (32N pendulum) (32N pendulum) (8Npendulum) (32N pendulum) Modulus of [MPal 717 629 723 698 628 elasticity (MD) Modulus of [MPa] 721 650 721 679 681 elasticity (TD)
Production of Monofilms by the Blowing Process

(22) Monofilms were produced in a 7-layer blown film system from Collin® having a die head diameter of 180 mm. Of the 7 extruders, 6 had a diameter of 30 mm (extruders B, C, D, E, F, G) and one a diameter of 45 mm (extruder A). The melt from extruder was on the inside of the bubble; the melt from extruder G was on the outside. The sequence of the layers, from the inside outward, was A, B, C, D, E, F, G. The monofilms produced had a thickness of 100 μm and the layers had a layer thickness of 15/14/14/14/14/14/15 μm in the monofilms. All the extruders were loaded with the same component. The films were slit before they were wound up.

(23) The components used and the properties of the monomaterial films are specified in table 4. The percentages by weight of component (B) specified in table 4 are understood to mean the percentages by weight of units derived from component (B) (polyamide-6,36 units) in the copolyamide, based on the total weight of the copolyamide.

(24) TABLE-US-00004 TABLE 4 V17 V18 V19 B20 B21 B22 Component P-1 P-3 FP-2 C-1 C-2 C-3 Component (B) [% by — — — 10.5 20.8 30.3 wt.] Tear [mN] 1913 4783 2917 3083 3804 9548 propagation (8N (8N (8N (8N (32N (32N resistance (MD) pendulum) pendulum) pendulum) pendulum) pendulum) pendulum) Tear [mN] 1823 5325 5638 2909 5767 22287 propagation (8N (8N (8N (8N (8N (8N resistance (TD) pendulum) pendulum) pendulum) pendulum) pendulum) pendulum) Puncture energy [J] 5.7 6.0 0.6 6.1 7.3 5.7 (50% AH) Modulus of [MPa] 635 411 188 536 412 329 elasticity (MD) Modulus of [MPa] 656 410 187 510 446 356 elasticity (TD) Stability in 25% 0 X 0 0 0 sulfuric acid
Production of Multilayer Films in a Blowing Process

(25) Multilayer films comprising three different materials were produced in a 7-layer blown film system from Collin® with a die head diameter of 180 mm. Of the 7 extruders, 6 had a diameter of 30 mm and one a diameter of 45 mm. The multilayer films obtained had a thickness of 100 μm and the layers had a layer thickness, of 15/14/14/14/14/15 μm. The extruders of the blown film system were charged with the components in accordance with the makeup of the multilayer films specified in table 5. Table 5 also states the properties of the multilayer films produced. The percentages by weight of component (B) specified in table 5 are understood to mean the percentages by weight of units derived from component (B) (polyamide-6,36 units) in the copolyamide, based on the total weight of the copolyamide.

(26) TABLE-US-00005 TABLE 5 V23 V24 B25 B26 B27 Makeup FP-1 // FP-3 // FP-1 // FP-3 // FP-1 // FP-3 // FP-1 // FP-3 // FP-1 // FP-3 // P-1 // P-1 // P-1 // P-3 // P-3 // P-3 // C-1 // C-1 // C-1 // C-2 // C-2 // C-2 // C-3 // C-3 // C-3 // FP-3 // FP-1 FP-3 // FP-1 FP-3 // FP-1 FP-3 // FP-1 FP-3 // FP-1 Component (B) [% by — — 10.5 20.8 30.3 wt.] Tear propagation [mN] 1461 2826 1950 3109 5181 resistance (MD) (8N pendulum) (8N pendulum) (8N pendulum) (8N pendulum) (8N pendulum) Tear propagation [mN] 1461 2824 2122 3468 4318 resistance (TD) (8N pendulum) (8N pendulum) (8N pendulum) (8N pendulum) (8N pendulum) Puncture energy [J] 1.3 0.6 1.3 3.7 4.0 Modulus of [MPa] 377 312 321 316 280 elasticity (MD) Modulus of [MPa] 391 307 356 326 307 elasticity (TD)
Production of Multilayer Films in a Blowing Process

(27) Multilayer films comprising five different polymers were produced in a 7-layer blown film system from Collin® with a die head diameter of 180 mm. Of the 7 extruders, 6 had a diameter of 30 mm and one a diameter of 45 mm. The multilayer films obtained had a thickness of 100 μm and the layers had a layer thickness of 15/14/14/14/14/15 μm. The extruders of the blown film system were charged with the components in accordance with the makeup of the multilayer films specified in table 6. Table 6 also states the properties of the multilayer films produced. The percentages by weight of component (B) specified in table 6 are understood to mean the percentages by weight of units derived from component (B) (polyamide-6,36 units) in the copolyamide, based on the total weight of the copolyamide.

(28) TABLE-US-00006 TABLE 6 V28 V29 B30 B31 B32 Makeup FP-1 // FP-3 // FP-1 // FP-3 // FP-1 // FP-3 // FP-1 // FP-3 // FP-1 // FP-3 // P-1 // FP-5 // P-1 // P-3 // FP-5 // P-3 // C-1 // FP-5 // C-1 // C-2 // FP-5 // C-2 // C-3 // FP-5 // C-3 // FP-3 // FP-1 FP-3 // FP-1 FP-3 // FP-1 FP-3 // FP-1 FP-3 // FP-1 Component (B) [% by — — 10.5 20.8 30.3 wt.] Tear propagation [mN] 1975 6401 1875 6194 10042 resistance (MD) (8N pendulum) (32N pendulum) (8N pendulum) (32N pendulum) (32N pendulum) Tear propagation [mN] 2325 8062 1975 9637 13530 resistance (TD) (8N pendulum) (8N pendulum) (8N pendulum) (8N pendulum) (8N pendulum) Puncture energy [J] 0.7 0.8 1.2 1.2 0.9 Modulus of [MPa] 814 709 878 778 714 elasticity (MD) Modulus of [MPa] 793 710 421 672 593 elasticity (TD)
Production of Monofilms in the Blowing Process

(29) Monofilms were produced in a 7-layer blown film system from Collin® with a die head diameter of 180 mm. Of the 7 extruders, 6 had a diameter of 30 mm and one a diameter of 45 mm. The monomaterial films produced had a thickness of 100 μm and the layers had a layer thickness of 15/14/14/14/14/14/15 μm. All the extruders were loaded with the same component.

(30) The components used and the properties of the monofilms are specified in table 7. The percentages by weight of component (B) specified in table 7 are understood to mean the percentages by weight of units derived from component (B) (polyamide-6,36 units) in the copolyamide, based on the total weight of the copolyamide.

(31) TABLE-US-00007 TABLE 7 V33 V34 B35 Component P-1 P-3 0-4 Component (B) [% by — — 28.9 wt.] Tear propagation [mN] 1910 4408 8654 resistance (MD) (8N (8N (32N pendulum) pendulum) pendulum) Tear propagation [mN] 1736 4057 11436 resistance (TD) (8N (8N (32N pendulum) pendulum) pendulum) Modulus of [MPa] 666 484 297 elasticity (MD) Modulus of [MPa] 678 457 299 elasticity (TD)
Production of Multilayer Films in the Blowing Process

(32) Multilayer films were produced in a 7-layer blown film system from Collin® with a die head diameter of 180 mm. Of the 7 extruders, 6 had a diameter of 30 mm and one a diameter of 45 mm. The monomaterial films produced had a thickness of 100 μm and the layers had a layer thickness of 15/14/14/14/14/14/15 μm. All the extruders were loaded with the same component.

(33) The components used and the properties of the monomaterial films are specified in table 8. The percentages by weight of component (B) specified in table 8 are understood to mean the percentages by weight of units derived from component (B) (polyamide-6,36 units) in the copolyamide, based on the total weight of the copolyamide.

(34) TABLE-US-00008 TABLE 8 V36 V37 B38 Makeup FP-1 // FP-3 // FP-1 // FP-3 // FP-1 // FP-3 // P-1 // FP-5 // P-3 // FP-5 // C-4 // FP-5 // P-1 // P-3 // C-4 // FP-3 // FP-1 FP-3 // FP-1 FP-3 // FP-1 Component [% by — — 28.9 (B) wt.] Tear [mN] 1932 3079 15149 propagation (8N (32N (32N resistance pendulum) pendulum) pendulum) (MD) Tear [mN] 2276 6124 10110 propagation (8N (8N (32N resistance pendulum) pendulum) pendulum) (TD) Modulus of [MPa] 990 824 746 elasticity (MD) Modulus of [MPa] 966 784 728 elasticity (TD)

(35) The above examples show that the copolyamide of the invention can significantly increase the tear propagation resistance of the agricultural films (AF) both in extrusion direction and at right angles thereto. The modulus of elasticity and puncture resistance of the agricultural films (AF) of the invention are also within a range acceptable for practical use, and so the agricultural films (AF) of the invention have advantageous properties overall, especially for use in the agricultural sector.