FILMS FOR AGRICULTURAL STRUCTURES

Abstract

A film for covering agricultural structures, including: a) a polymeric film having one or more layers, wherein at least one of the layers includes one or more UV stabilisers; and b) a coating on at least one outer surface of the polymeric film, the coating including at least one layer containing a polymer, such that the film has an oxygen permeability below 500 ml/m.sup.2/bar/day at 23° C. and 0% relative humidity, as measured according to EN ISO 15105-2.

Claims

1-31. (canceled)

32. A film for covering agricultural structures, comprising: a) a polymeric film having one or more layers, wherein at least one of the layers comprises one or more UV stabilisers, and b) a coating on at least one outer surface of the polymeric film, the coating comprising at least one layer comprising a polymer, such that the film has an oxygen permeability below 500 ml/m.sup.2/bar/day at 23° C. and 0% relative humidity, as measured according to EN ISO 15105-2, wherein each layer of the coating is formed by depositing a solution to form a layer and drying the layer.

33. The film according to claim 32, wherein the oxygen permeability of the film is below 200 ml/m.sup.2/bar/day.

34. The film according to claim 32, wherein the film has a permeability to water vapour below 100 g/m.sup.2/day at 38° C. and 90% relative humidity, as measured according to ASTM E96.

35. The film according to claim 32, wherein the at least one layer of the coating comprising the polymer has a thickness of from 0.1 μm to 5 μm.

36. The film according to claim 32, wherein the coating comprises: one or more inorganic particles independently selected from the group consisting of SiO.sub.2, Al.sub.2O.sub.3, TiO.sub.2, AlCl.sub.3, MgO, ZnO, CuO, Fe.sub.2O.sub.3, clays, and combinations thereof; and/or one or more organic molecules independently selected from the group consisting of acrylic resins, epoxy resins, polyurethanes, polyimines, polysiloxanes, surfactants, binders and combinations thereof.

37. The film according to claim 32, wherein the polymer in the coating is a vinylidene chloride homopolymer, a vinylidene chloride copolymer, a vinyl alcohol homopolymer, or a vinyl alcohol copolymer.

38. The film according to claim 37, wherein the vinylidene chloride copolymer comprises at least 20 wt. % of the vinylidene chloride monomer based on the total weight of the vinylidene chloride copolymer; and/or wherein the vinylidene chloride copolymer comprises less than 95 wt. % of the vinylidene chloride monomer based on the total weight of the vinylidene chloride copolymer.

39. The film according to claim 37, wherein the vinyl alcohol copolymer is a copolymer of vinyl alcohol and vinyl acetate.

40. The film according to claim 37, wherein the total amount of vinyl alcohol and vinyl acetate monomers in the vinyl alcohol copolymer is at least 20 wt. % based on the total weight of the vinyl alcohol copolymer; and/or wherein the total amount of vinyl alcohol and vinyl acetate monomers in the vinyl alcohol copolymer is less than 95 wt. % based on the total weight of the vinyl alcohol copolymer.

41. The film according to claim 37, wherein the number of vinyl alcohol monomers in the vinyl alcohol copolymer is at least 80% of the total number of vinyl alcohol and vinyl acetate monomers.

42. The film according to claim 37, wherein one or more vinyl alcohol monomers in the vinyl alcohol homopolymer or the vinyl alcohol copolymer has been modified by carboxylation, etherification, acetalization, carbamation, amination, sulfation, or esterification; and/or one or more vinyl alcohol monomers are bonded to side chains of the vinyl alcohol homopolymer or the vinyl alcohol copolymer.

43. The film according to claim 37, wherein the vinyl alcohol homopolymer or the vinyl alcohol copolymer is cross-linked, optionally by a cross-linking agent.

44. The film according to claim 43, wherein the cross-linking agent is selected from the group consisting of alcohols, straight-chain polyols, branched-chain polyols, aldehydes, amines, polyamines, hydrazides, polyhydrazides, metal salts, acids, organic acids, ethylene glycol, formaldehyde, acetaldehyde, glyoxal, malondialdehyde, succindialdehyde, glutaraldehyde, meta-xylenediamine, 1,3-bis (aminomethyl) cyclohexane, adipic dihydrazide, dodecane dihydrazide, polyol carbonyl adduct, sodium borate, ammonium zirconium carbonate, sodium glyoxylate, malonic acid, succinic acid, adipic acid, boric acid, and sulfosuccinic acid.

45. The film according to claim 37, wherein the vinylidene chloride copolymer is a copolymer of vinylidene chloride and one or more monomers of formula (I) and/or the vinyl alcohol copolymer is a copolymer of vinyl alcohol, optionally vinyl acetate, and one or more monomers of formula (I): ##STR00008## wherein each R.sup.1 is independently selected from the group consisting of H, C.sub.1-C.sub.10 alkyl, C.sub.3-C.sub.10 cycloalkyl, C.sub.1-C.sub.10 alkoxy, (C.sub.1-C.sub.5 alkyl)-O-(C.sub.1-C.sub.5 alkyl), C.sub.6-C.sub.10 aryl, C.sub.1-C.sub.9 heteroaryl, nitrile, —OH, halo, —C(O)R.sup.4, —C(O)OR.sup.4, —OC(O)R.sup.4, —C(O)NHR.sup.4, and —NHC(O)R.sup.4; each R.sup.2 is independently selected from the group consisting of H, halo, C.sub.1-C.sub.3 alkyl, —C(O)OR.sup.5, and —CH.sub.2C(O)OR.sup.5; each R.sup.3 is independently selected from the group consisting of H, —C(O)OR.sup.5, and C.sub.1-C.sub.3 alkyl; each R.sup.4 is independently selected from the group consisting of H, C.sub.1-C.sub.10 alkyl, C.sub.3-C.sub.10 cycloalkyl, (C.sub.1-C.sub.5 alkyl)-O-(C.sub.1-C.sub.5 alkyl), C.sub.6-C.sub.10 aryl, and C.sub.1-C.sub.9 heteroaryl; and each R.sup.5 is independently selected from C.sub.1-C.sub.10 alkyl; wherein each C.sub.1-C.sub.10 alkyl, C.sub.3-C.sub.10 cycloalkyl, C.sub.1-C.sub.10 alkoxy, (C.sub.1-C.sub.5 alkyl)-O-(C.sub.1-C.sub.5 alkyl), C.sub.6-C.sub.10 aryl and C.sub.1-C.sub.9 heteroaryl is optionally independently substituted with one or more substituents independently selected from —OH, oxo, —SO.sub.2H, —NO.sub.2, and halo.

46. The film according to claim 37, wherein the vinylidene chloride copolymer is a copolymer of vinylidene chloride and one or more additional monomers and/or the vinyl alcohol copolymer is a copolymer of vinyl alcohol, optionally vinyl acetate, and one or more additional monomers, wherein the one or more additional monomers are independently selected from the group consisting of alkenes, acrylates, vinyl halides, vinyl amides, styrenes, vinyl alcohols, vinyl esters, vinyl ethers, vinyl ketones, maleic acid, maleates, fumaric acid, fumarates, itaconic acid, itaconates, crotonic acid and crotonates.

47. The film according to claim 37, wherein the vinylidene chloride copolymer is a copolymer of vinylidene chloride and one or more additional monomers independently selected from the group consisting of ethene, propene, butene, acrylic acid, methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, hydroxyethyl acrylate, methacrylic acid, methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, acrylonitrile, methacrylonitrile, vinyl chloride, styrene, methyl vinyl ketone, vinyl alcohol, vinyl acetate, and itaconic acid.

48. The film according to claim 37, wherein the vinyl alcohol copolymer is a copolymer of vinyl alcohol, optionally vinyl acetate, and one or more additional monomers independently selected from the group consisting of ethene, propene, butene, acrylic acid, methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, hydroxyethyl acrylate, methacrylic acid, methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, acrylonitrile, methacrylonitrile, vinyl chloride, vinylidene chloride, styrene, methyl vinyl ketone, and itaconic acid.

49. The film according to claim 32, wherein the coating comprises a vinylidene chloride homopolymer or a vinylidene chloride copolymer.

50. The film according to claim 32, wherein the coating comprises more than one layer, and at least one layer of the coating comprises the polymer.

51. The film according to claim 32, wherein the coating comprises a single layer comprising the polymer.

52. The film according to claim 32, comprising a coating on both outer surfaces of the polymeric film, wherein each coating comprises at least one layer comprising a polymer, such that the film has an oxygen permeability below 500 ml/m.sup.2/bar/day at 23° C. and 0% relative humidity, as measured according to EN ISO 15105-2; wherein each layer of the coating is formed by depositing a solution to form a layer and drying the layer.

53. The film according to claim 32, wherein the one or more layers of the polymeric film each independently comprise one or more polymers independently selected from the group consisting of low density polyethylene (LDPE), low density linear polyethylene (LLDPE), metallocene low density linear polyethylene (MLLDPE), ethylene-vinyl acetate copolymer (EVA), ethylene butyl acrylate copolymer (EBA), high density polyethylene (HDPE), polypropylene (PP), thermoplastic polyurethane (TPU), polyethylene terephthalate (PET), polyvinyl chloride (PVC), polyamide (PA), ethylene-vinyl alcohol copolymer (EVOH), and combinations thereof; and/or wherein at least one of the layers of the polymeric film further comprises IR absorbers, anti-fogging agents, anti-dripping agents, anti-dust materials, anti-algae materials, adhesion assistant materials, and/or pigments.

54. The film according to claim 32, wherein the one or more UV stabilisers are independently selected from the group consisting of Hindered Amine Light Stabilizers (HALS), UV-absorbers, and nickel organic complexes; and/or wherein the one or more UV stabilisers are present in an amount of from 0.1 wt. % to 20 wt. % based on the total weight of the layer.

55. The film according to claim 32, wherein the polymeric film has from 1 to 100 layers; and/or wherein the polymeric film is obtained by extrusion or co-extrusion; and/or wherein the film has a total thickness of from 25 μm to 500 μm and a total width of from 1 m to 60 m.

56. An agricultural structure, wherein at least a portion of the agricultural structure is covered with the film according to claim 32.

57. A method of covering an agricultural structure, comprising covering at least a portion of the agricultural structure with the film according to claim 32.

58. A method of producing a film for covering agricultural structures, comprising: i) providing a polymeric film comprising one or more layers, wherein at least one of the layers comprises one or more UV stabilisers; and ii) depositing a coating on at least one outer surface of the polymeric film, the coating comprising at least one layer comprising a polymer, such that the film has an oxygen permeability below 500 ml/m.sup.2/bar/day at 23° C. and 0% relative humidity, as measured according to EN ISO 15105-2, wherein each layer of the coating is formed by depositing a solution to form a layer and drying the layer.

59. The method of producing a film according to claim 58, wherein the coating is deposited via dipping, spraying, flexography, plasma, laser, gravure printing, reverse roll, roll to roll, knife-over-all, rod coater, jet printing, or slot die; and/or wherein the outer surface of the polymeric film is treated with corona and/or plasma prior to deposition of the coating; and/or wherein the method further comprises producing the polymeric film via blown or cast extrusion or co-extrusion.

Description

EXAMPLES

Example 1

[0150] A transparent greenhouse film having a thickness of 180 μm and a width of 12 meters was produced on a seven-layer blown film line with an 1800 mm die, at an output of 1300 kg/h and a speed of 11 m/min. The composition of the layers of the film is show in Table 1 below. The film was corona treated and sprayed on one side with a 50% aqueous solution of a copolymer of vinylidene chloride, methyl acrylate, acrylonitrile, and hydroxyethyl acrylate (Diofan 050 from Solvay), to form a coating. The thickness of the coating was 0.8 μm.

TABLE-US-00001 TABLE 1 Layer 1 LDPE + MLLDPE + UV Layer 2 LDPE + MLLDPE + UV Layer 3 LDPE + LLDPE + UV Layer 4 LDPE + LLDPE + UV Layer 5 LDPE + LLDPE + UV Layer 6 EVA + UV + IR Layer 7 LDPE + MLLDPE + UV

[0151] LDPE=Low Density Polyethylene; LLDPE=Linear Low Density Polyethylene; MLLDPE=Metallocene Linear Low density Polyethylene; EVA=Ethylene Vinyl Acetate copolymer with 14% Vinyl Acetate content; UV=UV masterbatch containing combinations of UV stabilizers (UV20H containing 20% HALS Chimassorb 944); IR=IR masterbatch containing an infrared absorber.

Example 2

[0152] A black/white silage film having a thickness of 100 μm and a width of 12 meters wide was produced on a seven-layer blown film line with an 1800 mm die, at an output of 1300 kg/h and a speed of 19 m/min. The composition of the layers of the film is shown in Table 2 below. The film was corona treated and then immersed in a tank containing a 58% w.w. aqueous solution of a copolymer of vinylidene chloride (Diofan 063 from Solvay), to form a coating of the polymer on one side of the film. The thickness of the coating was 1 μm. Immediately after dipping of the film, it passed through dryers where the water was evaporated, the film was cooled and wrapped in rolls.

TABLE-US-00002 TABLE 2 Layer 1 LDPE + MLLDPE + White + UV Layer 2 LDPE + MLLDPE + White + UV Layer 3 LDPE + LLDPE + UV Layer 4 LDPE + LLDPE + UV Layer 5 LDPE + LLDPE + UV Layer 6 LDPE + MLLDPE + Black Layer 7 LDPE + MLLDPE + Black

[0153] White=White masterbatch containing 70% Titanium Dioxide in PE carrier; Black=Black masterbatch containing 40% carbon black in PE carrier. The remaining abbreviations in Table 2 are as defined above for Table 1.

Comparative Example 1

[0154] A seven-layer film having a thickness of 180 μm as defined in Table 3 below.

TABLE-US-00003 TABLE 3 Layer 1 LDPE + MLLDPE + UV Layer 2 LDPE + MLLDPE + UV Layer 3 LDPE + LLDPE + UV Layer 4 LDPE + LLDPE + UV Layer 5 LDPE + LLDPE + UV Layer 6 EVA + UV + IR Layer 7 LDPE + MLLDPE + UV

[0155] The abbreviations in Table 3 are defined as above.

Comparative Example 2

[0156] A seven-layer 100 μm silage film having a 2.5 μm EVOH layer in the middle. The composition of the layers of the film is shown in Table 4 below.

TABLE-US-00004 TABLE 4 Layer 1 LDPE + MLLDPE + UV Layer 2 LDPE + MLLDPE + Green + UV Layer 3 LDPE + TIE + UV Layer 4 EVOH 44% Layer 5 LLDPE + TIE + UV Layer 6 LDPE + MLLDPE + Silver + UV Layer 7 LDPE + MLLDPE + UV

[0157] Green=Green masterbatch containing green pigment in PE carrier; Silver=Silver masterbatch, containing aluminum pigment ion PE carrier; EVOH 44%=Ethylene Vinyl Alcohol 44% mol; TIE=tie layer resin. The remaining abbreviations in Table 4 are defined as above.

[0158] Permeability to Oxygen

[0159] The oxygen permeability of the films for the examples and comparative examples was measured according to standard EN ISO 15105-2 (23° C., 0% RH). The results are shown in Table 5 below.

TABLE-US-00005 TABLE 5 Oxygen Permeability Example (cm.sup.3/cm.sup.2/day) Example 1 10 at 1 bar Comparative Example 1 900 at 1 bar Example 2 15 at 0.2 bar Comparative Example 2 14 at 0.2 bar

[0160] The film of Example 1, having a coating comprising a vinylidene chloride copolymer on the surface of the film, has a significantly lower oxygen permeability than Comparative Example 1, without such a coating. This demonstrates that the coating comprising a vinylidene chloride homopolymer or copolymer provides the film with a low oxygen permeability.

[0161] Permeability to Agrochemicals

[0162] The films of Example 1 and Comparative Example 1 were used to cover two identical metal structures (dimensions of the metal structure: 1850 cm×1100 cm×1000 cm). A sulphur burner, which sublimes sulphur using an infrared lamp, was hung from the middle of the roof of each metal structure (and at distance of 40 cm from it). The sulphur burner was turned on for 30 minutes a day for a total of 3 days. The sulphur burner acts as a source of sulphur inside the metal structure, to simulate agrochemicals decomposing under the influence of heat and UV radiation and creating active compounds, such as sulphur.

[0163] Afterwards, film samples were taken from both films at the top of the two structures. The film samples were mechanically rubbed to remove the sulphur from their surface and the sulphur concentrations were then measured using a sulphur analyser from Mitsubishi Chemical.

[0164] The results of the sulphur analysis are shown in Table 6 below. As can be seen, the sulphur content of the sample from the film of Example 1 is significantly lower than in the sample of the film from Comparative Example 1. This demonstrates that the oxygen barrier coating on the outer surface of the polymeric film of Example 1 reduces the permeability of the film to sulphur thereby reducing the deactivation of the UV stabilisers in the polymeric film. The films of the present invention thus demonstrate a reduced susceptibility to photodegradation in the presence of agrochemicals.

TABLE-US-00006 TABLE 6 Sulphur content Example (ppm) Example 1 384 Comparative Example 1 1398

[0165] Dart Drop Impact Resistance

[0166] The dart drop impact resistance of the films of Example 2 and Comparative Example 2 was measured according to standard EN ISO 77651. The results are shown in Table 7 below.

TABLE-US-00007 TABLE 7 Dart Drop Impact Example Resistance (gr) Example 2 900 Comparative Example 2 500

[0167] The film of Comparative Example 2 comprises a coextruded EVOH barrier layer in the middle of the film. This provides the film with an oxygen permeability of 14 cm3/cm2/day at 0.2 bar, as referenced above. However, this coextruded barrier layer negatively affects the mechanical properties of the film. For example, the dart drop impact resistance of the film of Comparative Example 2 is only 500 gr.

[0168] In contrast, the film of Example 2 has a similarly low oxygen permeability of 15 cm3/cm2/day at 0.2 bar, but a significantly better dart drop impact resistance of 900 gr. Therefore, the barrier coating of Example 2 provides the film with a low oxygen permeability, but improved mechanical properties compared to the coextruded barrier layer of comparative Example 2.

[0169] This demonstrates that the films of the present invention have low permeability to oxygen gas (and therefore a reduced susceptibility to photodegradation in the presence of agrochemicals as demonstrated above by Example 1), while maintaining excellent mechanical properties.

[0170] Permeability to Water Vapour

[0171] The permeability of the films of Example 1 and Comparative Example 1 to water vapour were measured according to standard ASTM E96 (T=38° C., Δ(RH)=90%). The results are shown in Table 8 below.

TABLE-US-00008 TABLE 8 Permeability to Water Vapour Example (g/m.sup.2/day) Example 1 2.4 Comparative Example 1 2.4

Comparative Example 3

[0172] A coextruded film was prepared with the composition as defined in Table 9 below.

TABLE-US-00009 TABLE 9 Layer 1 MLLDPE + additives Layer 2 MLLDPE + additives + tie materials Layer 3 MLLDPE + 56% polyamide + additives

[0173] The mechanical properties of this film are detailed in Table 10 below.

TABLE-US-00010 TABLE 10 Strength, machine 21.0 direction (Mpa) Strength, transverse 16.0 direction (Mpa) Elongation, machine 408 direction (%) Elongation, transverse 419 direction (%) Tear (gf/mic) 3.4 Dart Drop (gr) 550 IRT (%) 6.2 GLT (%) 84.3 Diff. T. (%) 70.2 IRT = Infrared transmittance; GLT = Global light transmittance; Diff. T. = Diffused transmittance.

[0174] It can be seen from Table 10 that the presence of a coextruded layer comprising polyamide in the film results in poor mechanical properties. The films of the present invention having a barrier coating do not suffer from these problems. For example, the film of Comparative Example 3 has a dart drop impact resistance of only 550 gr, whereas the film of Example 2 of the invention has a significantly higher dart drop impact resistance of 900 gr.

[0175] Numbered Embodiments of the Invention

[0176] Embodiment 1. A film for covering agricultural structures, comprising: [0177] a) a polymeric film having one or more layers, wherein at least one of the layers comprises one or more UV stabilisers; and [0178] b) a coating comprising a vinylidene chloride homopolymer or copolymer on at least one outer surface of the polymeric film.

[0179] Embodiment 2. A film according to embodiment 1, wherein the coating has a thickness of from 0.1 μm to 5 μm, preferably from 0.3 μm to 1.5 μm.

[0180] Embodiment 3. A film according to embodiment 1 or 2, wherein the coating comprises one or more inorganic particles independently selected from the group consisting of SiO.sub.2, Al.sub.2O.sub.3, TiO.sub.2, AlC13, MgO, ZnO, CuO, Fe.sub.2O.sub.3, and combinations thereof; and/or one or more organic molecules independently selected from the group consisting of acrylic resins, epoxy resins, polyurethanes, surfactants, and combinations thereof.

[0181] Embodiment 4. A film according to any preceding embodiment, wherein the vinylidene chloride copolymer comprises at least 20 wt. % of the vinylidene chloride monomer, preferably at least 40 wt. %, more preferably at least 50 wt. %, more preferably at least 60 wt. %, more preferably at least 70 wt. % most preferably at least 80 wt. %, based on the total weight of the copolymer; and/or [0182] wherein the vinylidene chloride copolymer comprises less than 95 wt. % of the vinylidene chloride monomer, preferably less than 90 wt. %, based on the total weight of the copolymer.

[0183] Embodiment 5. A film according to any preceding embodiment, wherein the vinylidene chloride copolymer is a copolymer of vinylidene chloride and one or more monomers of formula (I):

##STR00007##

[0184] wherein each R.sup.1 is independently selected from the group consisting of H, C.sub.1-C.sub.10 alkyl, C.sub.3-C.sub.10 cycloalkyl, C.sub.1-C.sub.10 alkoxy, (C.sub.1-C.sub.5 alkyl)-O-(C.sub.1-C.sub.8 alkyl), C.sub.6-C.sub.10 aryl, C.sub.1-C.sub.9 heteroaryl, nitrile, —OH, halo, —C(O)R.sup.4, —C(O)OR.sup.4, —OC(O)R.sup.4, —C(O)NHR.sup.4, and —NHC(O)R.sup.4;

[0185] each R.sup.2 is independently selected from the group consisting of H, halo, C.sub.1-C.sub.3 alkyl, —C(O)OR.sup.5, and —CH.sub.2C(O)OR.sup.5;

[0186] each R.sup.3 is independently selected from the group consisting of H, —C(O)OR.sup.5, and C.sub.1-C.sub.3 alkyl;

[0187] each R.sup.4 is independently selected from the group consisting of H, C.sub.1-C.sub.10 alkyl, C.sub.3-C.sub.10 cycloalkyl, (C.sub.1-C.sub.5 alkyl)-O-(C.sub.1-C.sub.5 alkyl), 06-010 aryl, and C.sub.1-C.sub.9 heteroaryl;

[0188] each R.sup.5 is independently selected from C.sub.1-C.sub.10 alkyl;

[0189] wherein each C.sub.1-C.sub.10 alkyl, C.sub.3-C.sub.10 cycloalkyl, C.sub.1-C.sub.10 alkoxy, (C.sub.1-C.sub.5 alkyl)-O-(C.sub.1-C.sub.5 alkyl), C.sub.6-C.sub.10 aryl and C.sub.1-C.sub.9 heteroaryl is optionally independently substituted with one or more substituents independently selected from —OH, oxo, —SO.sub.2H, —NO.sub.2, and halo.

[0190] Embodiment 6. A film according to any preceding embodiment, wherein the vinylidene chloride copolymer is a copolymer of vinylidene chloride and one or more monomers independently selected from the group consisting of alkenes, acrylates, vinyl halides, vinyl amides, styrenes, vinyl esters, vinyl ethers, vinyl ketones, maleic acid or maleates, fumaric acid or fumarates, itaconic acid or itaconates, crotonic acid or crotonates, preferably wherein the vinylidene chloride copolymer is a copolymer of vinylidene chloride and one or more monomers independently selected from the group consisting of acrylic acid, methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, hydroxyethyl acrylate, methacrylic acid, methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, acrylonitrile, methacrylonitrile, vinyl chloride, styrene, methyl vinyl ketone, vinyl acetate, and itaconic acid.

[0191] Embodiment 7. A film according to any preceding embodiment, comprising a coating on both outer surfaces of the polymeric film, wherein each coating is independently as defined in any of embodiments 1 to 6.

[0192] Embodiment 8. A film according to any preceding embodiment, wherein the one or more layers of the polymeric film each independently comprise one or more polymers independently selected from the group consisting of low density polyethylene (LDPE), low density linear polyethylene (LLDPE), ethylene-vinyl acetate copolymer (EVA), ethylene butyl acrylate copolymer (EBA), high density polyethylene (HDPE), polypropylene (PP), thermoplastic polyurethane (TPU), polyethylene terephthalate (PET), polyvinyl chloride (PVC), polyamide (PA), ethylene-vinyl alcohol copolymer (EVOH), and combinations thereof; and/or [0193] wherein at least one of the layers of the polymeric film further comprises IR absorbers, anti-fogging agents, anti-dripping agents, anti-dust materials, anti-algae materials, and/or pigments.

[0194] Embodiment 9. A film according to any preceding embodiment, wherein the one or more UV stabilisers are independently selected from the group consisting of Hindered Amine Light Stabilizers (HALS), UV-absorbers, and nickel organic complexes; and/or [0195] wherein the one or more UV stabilisers are present in an amount of from 0.1 wt. % to 20 wt. %, preferably from 0.1 wt. % to 10 wt. %, most preferably from 0.1 wt. % to 5 wt. %, based on the total weight of the layer.

[0196] Embodiment 10.A film according to any preceding embodiment, wherein the polymeric film has from 1 to 100 layers, preferably from 3 to 11 layers; and/or [0197] wherein the polymeric film is obtainable by co-extrusion, preferably blown-film or cast-film co-extrusion; and/or [0198] wherein the film has a total thickness of from 25 μm to 500 μm and a total width of from 1 m to 50 m; and/or [0199] wherein the film has an oxygen permeability below 500 ml/m.sup.2/day, preferably below 100 ml/m.sup.2/day, measured according to ASTM D3985 at 23° C. and 0% relative humidity.

[0200] Embodiment 11. The use of a coating comprising a vinylidene chloride homopolymer or copolymer on at least one outer surface of a polymeric film, wherein the polymeric film comprises one or more layers, at least one layer comprising one or more UV stabilisers, to reduce the susceptibility of the polymeric film to photodegradation in the presence of agrochemicals; and/or to reduce the permeability of the polymeric film to gas and/or water vapour.

[0201] Embodiment 12 An agricultural structure, characterised in that at least a portion thereof is covered with a film according to any of embodiments 1 to 10.

[0202] Embodiment 13.A method of covering an agricultural structure, comprising covering at least a portion of the agricultural structure with a film according to any of embodiments 1 to 10.

[0203] Embodiment 14.A method of producing a film for covering agricultural structures, comprising: [0204] i) providing a polymeric film comprising one or more layers, wherein at least one of the layers comprises one or more UV stabilisers; and [0205] ii) depositing a coating comprising a vinylidene chloride homopolymer or copolymer on at least one outer surface of the polymeric film.

[0206] Embodiment 15.A method of producing a film according to embodiment 14, wherein the coating is deposited via dipping, spraying, flexography, plasma, laser, gravure printing, reverse roll, roll to roll, knife-over-all, rod coater, jet printing, or slot die; and/or [0207] wherein the outer surface of the polymeric film is treated with plasma prior to deposition of the coating; and/or [0208] wherein the method further comprises producing the polymeric film via blown or cast co-extrusion.