Multilayer films that disintegrate easily in marine environments

Abstract

A multi-layer film comprising an aliphatic polyester, an aliphatic-aromatic polyester, one or more lactic acid polyesters and optionally an inorganic filler, a crosslinker and / or a chain extender, the multi-layer film being highly biodegradable in marine environments and highly disintegratable in home composting.

Description

[Technical field]

[0001] The present invention relates to polymer compositions that are particularly suitable for use in making films that are highly biodegradable in the marine environment and highly disintegratable in home composting. [Background technology]

[0002] Today, the issue of biodegradation in the marine environment is of great importance. It is well known that any substance, material or product released into nature poses potential ecological risks, and this is even more acute in the marine environment. The unregulated release of plastic products, biodegradable or not, into the marine environment causes enormous damage and therefore the end of compostable products must remain the purpose for which they were designed, namely industrial composting through separate collection and recovery of food waste and garden waste, making compost an essential tool for solving the challenge of soil degradation, which is becoming increasingly carbon poor and therefore increasingly uncultivated.

[0003] However, when plastic products are disposed of in nature, as unfortunately happens with all packaging materials (glass, aluminum, paper, etc.), it is desirable for them to biodegrade as quickly as possible to avoid environmental damage. For this reason, there is a particular need for polymer compositions that can be used in films that are biodegradable, compostable, and capable of rapidly biodegrading in the marine environment. Particularly desirable are polymer compositions that are capable of breaking down in a compostable aerobic environment at a temperature of 28° C., so that they can be disposed of by home composting after use, and that are biodegradable in seawater, so that they may be disposed of in the ocean by the action of microorganisms in the water.

[0004] These properties are not the only requirements: films obtained from these compositions must have excellent mechanical properties, such as stiffness and tensile strength, as well as optimal optical properties, such as transparency, for suitable commercial use. For example, WO / 2018 / 181500 and WO / 2017 / 087658 describe the use of compositions in which polyhydroxyalkanoates (PHAs) are combined with aliphatic aromatic polyesters or polybutylene succinates to produce films, but in this case they are poorly biodegradable at room temperature and in the marine environment.

[0005] JP2021055084A describes a film made from a marine biodegradable polyester containing an aliphatic polyester composition containing an aliphatic polyester resin (A) containing a repeating unit derived from an aliphatic diol and a repeating unit derived from an aliphatic dicarboxylic acid as main constituent units, a polyhydroxyalkanoate (B), and an inorganic filler (C), in which the polyhydroxyalkanoate (B) contains 3-hydroxybutyrate units and 3-hydroxyhexanoate units as main constituent units, and the mass ratio of the aliphatic polyester composition (A) to the polyhydroxyalkanoate (B) is 95 / 5 to 70 / 30. This film has relatively low transparency. Furthermore, in the composition described in JP2021055084A, the amount of polyhydroxyalkanoate is less than 30%, since it is known that this material does not allow high biodegradability. Summary of the Invention [Problem to be solved by the invention]

[0006] The problem underlying the present invention is therefore to provide a film that is characterized by being easily disintegrable at low temperatures under home composting conditions, being easily biodegradable in the marine environment, and having optimal mechanical and optical properties. [Means for solving the problem]

[0007] Surprisingly, it has been found that it is possible to solve this problem by polymer compositions made from aliphatic polyesters, which result in an increase in the low-temperature degradation of films obtained from such compositions, while maintaining, if not improving, their optical and mechanical properties. Moreover, such compositions can be easily used in blown film processes without requiring modifications to existing equipment. One object of the present invention is to provide a polymer composition for producing a film, which may be monolayer or multilayer.

[0008] The present invention relates in particular to a composition comprising: i) 10 to 49% by weight, preferably 14 to 45% by weight, more preferably 24 to 40% by weight, and even more preferably 35 to 40% by weight, based on the sum of components i to v, of at least one aliphatic polyester i, a) based on the total dicarboxylic acid component, a1) 60 to 95 mol %, preferably 70 to 85 mol %, of units derived from succinic acid; a2) 5 to 40 mol %, preferably 15 to 30 mol %, of units derived from at least one saturated dicarboxylic acid having a carbon atom number higher than 4; A dicarboxylic acid component comprising: b) based on the total diol component, the following: b1) 95 to 100 mol % of units derived from 1,4-butanediol; b2) 0 to 5 mol % of units derived from at least one saturated aliphatic diol other than 1,4-butanediol; Diol component containing aliphatic polyesters including i; ii) 0 to 15% by weight, preferably 1 to 5% by weight, of at least one aliphatic-aromatic polyester ii, c) based on the total dicarboxylic acid component, c1) 42 to 60 mol %, preferably 45 to 49.5 mol %, of units derived from at least one aromatic dicarboxylic acid; c2) 58 to 40 mol %, preferably 55 to 50.5 mol %, of units derived from at least one saturated aliphatic dicarboxylic acid; A dicarboxylic acid component comprising: d) based on the total diol content, the following: d1) 95 to 100 mol % of units derived from at least one saturated aliphatic diol; d2) 0 to 5 mol % of units derived from at least one unsaturated aliphatic diol; Diol component containing aliphatic-aromatic polyesters including II; iii) 51 to 90% by weight, preferably 55 to 86% by weight, more preferably 60 to 76% by weight, and even more preferably 60 to 65% by weight, of at least one lactic acid polyester, based on the total of components i to v; iv) 0 to 1.5% by weight, preferably 0.1 to 1.2% by weight, and more preferably 0.2 to 0.5% by weight, of at least one inorganic filler, based on the total of components i to v; v) 0 to 2.5% by weight, preferably 0.02 to 1.5% by weight, more preferably 0.1 to 1.0% by weight, based on the sum of components i to v, of at least one crosslinker and / or chain extender comprising at least one difunctional and / or polyfunctional compound having groups selected from isocyanates, peroxides, carbodiimides, isocyanurates, oxazolines, epoxides, anhydrides, divinyl ethers and mixtures thereof. The present invention relates to a polymer composition comprising:

[0009] The polymer compositions described above may be used to prepare monolayer or multilayer films. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] The aliphatic polyester of the composition according to the invention is present between 10 and 49% by weight of the total polymer compositions i-v, preferably between 14 and 45% by weight, even more preferably between 24 and 40% by weight, or even more preferably between 35 and 40% by weight.

[0011] The aliphatic polyester i of the composition according to the present invention comprises a dicarboxylic acid component comprising 60 to 95 mol %, preferably 70 to 85 mol %, of units derived from succinic acid (component a1) and 5 to 40 mol %, preferably 15 to 30 mol %, of units derived from at least one saturated dicarboxylic acid having more than 4 carbon atoms (component a2), based on the total dicarboxylic acid component.

[0012] The saturated aliphatic dicarboxylic acid other than succinic acid (component a2) of the aliphatic polyester i of the composition according to the present invention is preferably a C5-C 24 , more preferably C5 to C 13 , more preferably C5 to C 11 Saturated dicarboxylic acids, their C1-C 24 More preferably, the saturated aliphatic dicarboxylic acid other than succinic acid is selected from 2-ethylsuccinic acid, glutaric acid, 2-methylglutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, undecanedioic acid, dodecanedioic acid, brassylic acid and their C1 to C4 alkyl esters, salts thereof and mixtures thereof. 24 In one preferred embodiment of the present invention, the saturated aliphatic dicarboxylic acid other than succinic acid is selected from the group consisting of adipic acid, azelaic acid, sebacic acid and mixtures thereof. In one even more preferred embodiment of the present invention, the saturated aliphatic dicarboxylic acid other than succinic acid is azelaic acid.

[0013] The dicarboxylic acid component of the aliphatic polyester i of the composition according to the invention may contain up to 5% of unsaturated aliphatic dicarboxylic acids, which are preferably itaconic acid, fumaric acid, 4-methylene-pimelic acid, 3,4-bis(methylene)nonanedioic acid, 5-methylene-nonanedioic acid, their C1-C 24 In one preferred embodiment of the present invention, the unsaturated aliphatic dicarboxylic acid is selected from the group consisting of at least 50 mol %, preferably 60 mol % or more, more preferably 65 mol % or more of itaconic acid and its C1-C4 alkyl esters, their salts and mixtures thereof. 24, preferably a mixture including C1-C4 esters. More preferably, the unsaturated aliphatic dicarboxylic acid comprises itaconic acid.

[0014] The diol component of the aliphatic polyester i of the composition according to the invention may contain up to 5% of an unsaturated aliphatic diol, which is preferably selected from the group consisting of cis 2-butene-1,4-diol, trans 2-butene-1,4-diol, 2-butyne-1,4-diol, cis 2-pentene-1,5-diol, trans 2-pentene-1,5-diol, 2-pentyne-1,5-diol, cis 2-hexene-1,6-diol, trans 2-hexene-1,6-diol, 2-hexyne-1,6-diol, cis 3-hexene-1,6-diol, trans 3-hexene-1,6-diol, 3-hexene-1,6-diol.

[0015] In one particularly preferred embodiment, the aliphatic polyester i of the composition according to the invention is selected from the group consisting of poly(1,4-butylene succinate-co-adipate), poly(1,4-butylene succinate-co-1,4-butylene azelate), poly(1,4-butylene succinate-co-1,4-butylene sebacate). In an even more preferred embodiment, the aliphatic polyester i is poly(1,4-butylene succinate-co-1,4-butylene azelate).

[0016] The aliphatic polyester i of the composition according to the invention may advantageously further comprise repeat units derived from at least one hydroxy acid in an amount between 0 and 49 mol %, preferably between 0 and 30 mol %, relative to the total moles of the dicarboxylic acid components. Suitable examples of hydroxy acids are glycolic acid, hydroxybutyric acid, hydroxycaproic acid, hydroxyvaleric acid, 7-hydroxyheptanoic acid, 8-hydroxycaproic acid, 9-hydroxynonanoic acid, lactic acid or lactide. The hydroxy acids may be inserted into the chain as they are or may be reacted beforehand with a dicarboxylic acid or a diol.

[0017] Longer difunctional molecules with non-terminal functional groups may also be added in amounts up to 10 mol % based on the total moles of dicarboxylic acid components. Examples are dimer acid, ricinoleic acid and acids with epoxy functional groups, as well as polyoxyethylenes with molecular weights between 200 and 10,000. Diamines, amino acids and amino alcohols may also be present in proportions of up to 30 mole % based on the total moles of the dicarboxylic acid component.

[0018] In the process for producing the aliphatic polyesters i of the composition according to the invention, one or more polyfunctional molecules may advantageously be added in an amount between 0.1 and 3.0 moles relative to the total moles of dicarboxylic acid components (and hydroxy acids, if present), in order to obtain branched products. Examples of these molecules are glycerol, pentaerythritol, trimethylolpropane, citric acid, dipentaerythritol, monoanhydrosorbitol, monohydromannitol, acid triglycerides and polyglycerols.

[0019] The molecular weight Mn of the aliphatic polyester i of the composition according to the invention is preferably ≧20 000, more preferably ≧40 000. The polydispersity index Mw / Mn of the molecular weights is preferably between 1.5 and 10, more preferably between 1.6 and 5, even more preferably between 1.8 and 3.5. Molecular weight M n and M w may be measured using gel permeation chromatography (GPC) using a chromatographic system maintained at 40° C. using a set of two columns in series (mixed porosity of 5 μm and 3 μm particle sizes), a refractive index detector, chloroform as eluent (flow rate 0.5 ml / min) and polystyrene as reference standard.

[0020] The melt flow rate (MFR) of the aliphatic polyester i is preferably between 500 and 1 g / 10 min, more preferably between 100 and 3 g / 10 min, and even more preferably between 15 and 4 g / 10 min (measurement is carried out at 190° C. / 2.16 kg according to ISO 1133-1 “Plastics-determination of the melt mass-flow rate (MFR) and melt volume flow rate (MVR) of thermoplastics-Part 1: Standard method”).

[0021] The terminal acid group content of the aliphatic polyester i of the composition according to the invention is preferably between 15 and 160 meq / kg, more preferably between 30 and 100 meq / kg, even more preferably between 40 and 60 meq / kg. The acid end group content may be measured as follows: 1.5-3 g of polyester is placed in a 100 ml conical flask with 60 ml of chloroform. After the polyester is completely dissolved, 25 ml of 2-propanol is added, and immediately before analysis, 1 ml of deionized water is added. The resulting solution is titrated with a prestandardized ethanolic solution of NaOH. The equivalence point of the titration is determined using a suitable indicator, for example, a glass electrode for acid-base titrations in non-aqueous solvents. The acid end group content is calculated based on the consumption of the ethanolic NaOH solution according to the following formula:

number

[0022] Preferably, the aliphatic polyester i of the composition according to the invention has an intrinsic viscosity (measured in an Ubbelohde viscometer for a solution in CHCl3 at a concentration of 0.2 g / dl at 25° C.) greater than 0.3 dl / g, preferably between 0.3 and 2 dl / g, more preferably between 0.4 and 1.3 dl / g.

[0023] The aliphatic-aromatic polyester ii of the composition according to the invention is present between 0 and 15%, preferably between 1% and 5%, of the total polymer composition i-v. The aliphatic-aromatic polyester II comprises a dicarboxylic acid component containing 42 to 60 mol %, preferably 45 to 49.5 mol %, of units derived from at least one aromatic dicarboxylic acid (component C1), and 58 to 40 mol %, preferably 55 to 50.5 mol %, of units derived from at least one saturated aliphatic dicarboxylic acid (component C2), based on the total dicarboxylic acid component.

[0024] The aromatic dicarboxylic acids (component c1) of the aliphatic-aromatic polyesters II of the composition according to the invention are preferably selected from aromatic dicarboxylic acids of the phthalic acid type, preferably terephthalic acid or isophthalic acid, more preferably terephthalic acid, and heterocyclic aromatic dicarboxylic acid compounds, preferably 2,5-furandicarboxylic acid, 2,4-furandicarboxylic acid, 2,3-furandicarboxylic acid, 3,4-furandicarboxylic acid, their esters, salts and mixtures thereof.

[0025] The saturated aliphatic dicarboxylic acid (component c2) of the aliphatic-aromatic polyester ii is preferably a C2-C 24 , more preferably C4 to C 13 , more preferably C4 to C 11 Saturated dicarboxylic acids, their C1-C 24 More preferably, the saturated aliphatic dicarboxylic acid is selected from succinic acid, 2-ethylsuccinic acid, glutaric acid, 2-methylglutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, undecanedioic acid, dodecanedioic acid, brassylic acid and their C1-C alkyl esters, salts thereof and mixtures thereof.24 Preferably, the saturated dicarboxylic acid is selected from the group consisting of succinic acid, adipic acid, azelaic acid, sebacic acid, brassylic acid and mixtures thereof.

[0026] The dicarboxylic acid component of the aliphatic-aromatic polyester ii of the composition according to the invention may contain up to 5% of unsaturated aliphatic dicarboxylic acids, which are preferably itaconic acid, fumaric acid, 4-methylene-pimelic acid, 3,4-bis(methylene)nonanedioic acid, 5-methylene-nonanedioic acid, their C1-C 24 , preferably C1 to C4 alkyl esters, their salts and mixtures thereof.

[0027] In one preferred embodiment of the present invention, the unsaturated aliphatic dicarboxylic acid is at least 50 mol %, preferably 60 mol % or more, more preferably 65 mol % or more of itaconic acid, its C1-C 24 More preferably, the unsaturated aliphatic dicarboxylic acid comprises itaconic acid, more preferably a mixture comprising C1 to C4 esters.

[0028] The diol component of the aliphatic-aromatic polyester II of the composition according to the present invention contains, based on the total diol component, 95 to 100 mol %, preferably 97 to 100 mol %, of units derived from at least one saturated aliphatic diol (component D1), and 0 to 5 mol %, preferably 0 to 3 mol %, of units derived from at least one unsaturated aliphatic diol (component D2).

[0029] The saturated aliphatic diols (component d1) of the aliphatic-aromatic polyesters ii of the composition according to the invention are preferably 1,2-ethanediol, 1,2-propanediol, 1,3-propanediol, 1,3-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,1-undecanediol, 1,12-dodecanediol, 1,13-tridecanediol, The saturated aliphatic diol is selected from the group consisting of diols, 1,4-cyclohexanedimethanol, neopentyl glycol, 2-methyl-1,3-propanediol, dianhydrosorbitol, dianhydromannitol, dianhydroiditol, cyclohexanediol, cyclohexanemethanediol, dialkylene glycols and polyalkylene glycols having molecular weights of 100 to 4000, such as polyethylene glycol, polypropylene glycol, and mixtures thereof. Preferably, at least 50 mol% of the diol component comprises one or more diols selected from 1,2-ethanediol, 1,3-propanediol, and 1,4-butanediol. In one preferred embodiment of the present invention, the saturated aliphatic diol is derived from 1,4-butanediol.

[0030] The unsaturated aliphatic diols (component d2) of the aliphatic-aromatic polyesters ii of the composition according to the invention are preferably selected from the group consisting of cis 2-butene-1,4-diol, trans 2-butene-1,4-diol, 2-butyne-1,4-diol, cis 2-pentene-1,5-diol, trans 2-pentene-1,5-diol, 2-pentyne-1,5-diol, cis 2-hexene-1,6-diol, trans 2-hexene-1,6-diol, 2-hexyne-1,6-diol, cis 3-hexene-1,6-diol, trans 3-hexene-1,6-diol, 3-hexene-1,6-diol.

[0031] In one preferred embodiment, the aliphatic-aromatic polyester II is preferably poly(1,4-butylene adipate-co-1,4-butylene terephthalate), poly(1,4-butylene sebacate-co-1,4-butylene terephthalate), poly(1,4-butylene azelate-co-1,4-butylene terephthalate), poly(1,4-butylene brassylate-co-1,4-butylene terephthalate), poly(1,4-butylene succinate-co-1,4-butylene terephthalate), poly(1,4-butylene adipate-co-1,4-butylene sebacate-co-1,4-butylene terephthalate), poly (1,4-butylene azelate-co-1,4-butylene sebacate-co-1,4-butylene terephthalate), poly(1,4-butylene adipate-co-1,4-butylene azelate-co-1,4-butylene terephthalate), poly(1,4-butylene succinate-co-1,4-butylene sebacate-co-1,4-butylene terephthalate), poly(1,4-butylene adipate-co-1,4-butylene succinate-co-1,4-butylene terephthalate), poly(1,4-butylene azelate-co-1,4-butylene succinate-co-1,4-butylene terephthalate).

[0032] The aliphatic-aromatic polyesters II may also advantageously contain repeat units derived from at least one hydroxy acid in an amount of 0 to 49 mol %, preferably 0 to 30 mol %, based on the total moles of the dicarboxylic acid components. Suitable examples of hydroxy acids are glycolic acid, hydroxybutyric acid, hydroxycaproic acid, hydroxyvaleric acid, 7-hydroxyheptanoic acid, 8-hydroxycaproic acid, 9-hydroxynonanoic acid, lactic acid or lactide. The hydroxy acids may be inserted into the chain as they are or may be reacted beforehand with a dicarboxylic acid or a diol.

[0033] Longer difunctional molecules with non-terminal functional groups may also be added in amounts up to 10 mol % based on the total moles of dicarboxylic acid components. Examples are dimer acid, ricinoleic acid and acids with epoxy functional groups, as well as polyoxyethylenes with molecular weights between 200 and 10,000. Diamines, amino acids and amino alcohols may also be present in proportions of up to 30 mole % based on the total moles of the dicarboxylic acid component.

[0034] In the process for producing the aliphatic-aromatic polyesters II of the composition according to the invention, one or more polyfunctional molecules may advantageously be added in an amount between 0.05 and 3 mol % relative to the total moles of the dicarboxylic acid component (as well as any hydroxy acid) in order to obtain branched products. Examples of these molecules are glycerol, pentaerythritol, trimethylolpropane, citric acid, dipentaerythritol, monoanhydrosorbitol, monohydromannitol, acid triglycerides, and polyglycerols.

[0035] The molecular weight Mn of the aliphatic-aromatic polyester ii of the composition according to the invention is preferably ≧20 000, more preferably ≧40 000. The polydispersity index Mw / Mn of the molecular weights is preferably between 1.5 and 10, more preferably between 1.6 and 5, even more preferably between 1.8 and 2.7. Molecular weight M n and M w may be measured using the method described for the aliphatic polyester i.

[0036] The melt flow rate (MFR) of the aliphatic-aromatic polyester II is preferably between 500 and 1 g / 10 min, more preferably between 100 and 3 g / 10 min, and even more preferably between 15 and 3 g / 10 min (measurement is carried out at 190° C. / 2.16 kg according to ISO 1133-1 “Plastics—Determination of the melt mass-flow rate (MFR) and melt volume flow rate (MVR) of thermoplastics—Part 1: Standard method”).

[0037] The terminal acid group content of the aliphatic-aromatic polyester ii of the composition according to the invention is preferably at most 100 meq / kg, preferably at most 60 meq / kg, even more preferably at most 40 meq / kg. The terminal acid group content can be measured according to the method described for the aliphatic polyester i.

[0038] Preferably, the aliphatic-aromatic polyester ii of the composition according to the invention has an intrinsic viscosity (measured in an Ubbelohde viscometer for a solution in CHCl3 at a concentration of 0.2 g / dl at 25° C.) of more than 0.3 dl / g, preferably between 0.3 and 2.0 dl / g, more preferably between 0.4 and 1.1 dl / g.

[0039] The polyesters i and ii of the composition according to the invention may be synthesized according to any process known in the art. In particular, they may advantageously be obtained by polycondensation reactions. Advantageously, the synthesis process may be carried out in the presence of a suitable catalyst, including organometallic tin compounds such as stannic acid derivatives, titanium compounds such as ortho-butyl titanate, aluminum compounds such as Al-triisopropyl, antimony and zinc and zirconium compounds, and mixtures thereof. An example of a synthetic process that may be advantageously used to prepare polyesters is described in International Patent Application PCT2016050963.

[0040] In addition to components i and ii, the composition according to the invention comprises 51 to 90% by weight, preferably 55 to 86% by weight, even more preferably 60 to 76% by weight, or even more preferably 60 to 65% by weight, of at least one or more lactic acid polyesters (component iii), based on the sum of i to v. The lactic acid polyester is selected from the group consisting of poly-L-lactic acid, poly-D-lactic acid, poly-DL-lactic acid complex stereocomplex, copolymers containing more than 50 mol % of said lactic acid polyester, and mixtures thereof.

[0041] Particularly preferred are lactic acid copolymers which contain at least 95% by weight of repeating units derived from L-lactic acid or D-lactic acid or a combination thereof, have a molecular weight Mw of 50,000 or more, and have a shear viscosity of 50 to 250 Pa.s, preferably 80 to 200 Pa.s (according to ASTM standard D3835, T=190°C, shear rate=1000 s -1 , D=1 mm, L / D=10, measured on a dry polymer (water content less than 400 ppm).

[0042] In one particularly preferred embodiment of the invention, the lactic acid polyester contains at least 96% by weight of units derived from L-lactic acid, ≦4% by weight of repeating units derived from D-lactic acid, and has a melting temperature in the range of 160-180° C., a glass transition temperature (Tg) in the range of 55-65° C., and a MFR in the range of 10-50 g / 10 min (measured according to ISO 1133-1 at 190° C. and 2.16 kg). Commercially available examples of lactic acid polyesters having such properties include Ingeo TM Branded products include Biopolymer 3251D and Luminy® L105.

[0043] The composition according to the invention preferably comprises 0 to 1.5% by weight, preferably between 0.1 and 1.2% by weight, even more preferably between 0.2 and 0.5% by weight of the sum of components i to v, of at least one inorganic filler (component iv), which is preferably selected from the group consisting of kaolin, barytes, clay, talc, calcium and magnesium carbonates, iron and lead carbonates, aluminium hydroxide, diatomaceous earth, aluminium sulphate, barium sulphate, silica, mica, titanium dioxide and wollastonite.

[0044] In one preferred embodiment of the invention, the inorganic filler comprises one or more of talc, mica, calcium carbonate, silica or mixtures thereof present in the form of particles having an arithmetic mean diameter of less than or equal to 10 μm, more preferably less than or equal to 2 μm, measured relative to the major axis of the particle (measured according to ASTM 13320). In a preferred aspect of the invention, the inorganic filler is silica.

[0045] The composition according to the present invention preferably comprises 0-2.5% by weight, more preferably 0.02-1.5% by weight, even more preferably 0.1-1.0% by weight of at least one crosslinker and / or chain extender (component v) based on the total weight of components i-v, said component v improving the stability against hydrolysis and providing the following: Preferably, the crosslinking agent and / or the chain extender comprises at least one di- and / or polyfunctional compound having an epoxide or carbodiimide group.

[0046] Preferably, the crosslinking agent and / or chain extender comprises at least one di- and / or polyfunctional compound having an isocyanate group. More preferably, the crosslinking agent and / or chain extender comprises at least 25% by weight of one or more di- and / or polyfunctional compounds having an isocyanate group. Particularly preferred is a mixture of a di- and / or polyfunctional compound having an isocyanate group and a di- and / or polyfunctional compound having an epoxide group, which even more preferably comprises at least 75% by weight of a di- and / or polyfunctional compound having an isocyanate group.

[0047] Preferably, the di- and polyfunctional compounds having isocyanate groups are p-phenylene diisocyanate, 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, 4,4-diphenylmethane diisocyanate, 1,3-phenylene-4-chlorodiisocyanate, 1,5-naphthalene diisocyanate, 4,4-diphenylene diisocyanate, 3,3'-dimethyl-4,4-diphenylmethane diisocyanate, 3-methyl-4,4'-diphenylmethane diisocyanate, diphenyl ether diisocyanate, 2,4-cyclohexane ...1,3-phenylene-4-chlorodiisocyanate, 1,3-phenylene-4-chlorodiisocyanate, 1,5-naphthalene diisocyanate, 1,3-phenylene-4-chlorodiisocyanate, 1,3-phenylene-4-chlorodiisocyanate, 1,3-phenylene-4-chlorodiisocyanate, 1,3-phenylene-4-chlorodiisocyanate, 1,3-phenylene-4-chlorodiisocyanate, 1,3-phenylene-4-chlorodiisocyanate, 1,3-phenylene-4-chlorodiisocyanate, 1,3-phenylene-4-chlorodiisocyanate, 1,3-phenylene-4-chloro The isocyanate is selected from the group consisting of 2,3-cyclohexane diisocyanate, 1-methyl-2,4-cyclohexyl diisocyanate, 1-methyl-2,6-cyclohexyl diisocyanate, bis(isocyanatocyclohexyl)methane, 2,4,6-toluene triisocyanate, 2,4,4-diphenyl ether triisocyanate, polymethylene-polyphenyl-polyisocyanate, methylene diphenyl diisocyanate, triphenylmethane triisocyanate, 3,3'-dithiolylene-4,4-diisocyanate, 4,4'-methylene bis(2-methylphenylisocyanate), hexamethylene diisocyanate, 1,3-cyclohexylene diisocyanate, 1,2-cyclohexylene diisocyanate, and mixtures thereof. In a preferred embodiment, the compound having an isocyanate group is 4,4-diphenylmethane-diisocyanate.

[0048] The di- and polyfunctional compounds having peroxide groups are preferably selected from the group consisting of benzoyl peroxide, lauroyl peroxide, isononanoyl peroxide, di(t-butylperoxyisopropyl)benzene, t-butyl peroxide, dicumyl peroxide, α,α'-di(t-butylperoxy)diisopropylbenzene, 2,5-dimethyl-2,5-di(t-butylperoxy)hexane, t-butylcumyl peroxide, di-t-butyl peroxide, 2,5-dimethyl-2,5-di(t-butylperoxy)hex-3-yne, di(4-t-butylcyclohexyl)peroxydicarbonate, dicetyl peroxycarbonate, dimyristyl peroxycarbonate, 3,6,9-triethyl-3,6,9-trimethyl-1,4,7-triperoxonane, di(2-ethylhexyl)peroxycarbonate and mixtures thereof.

[0049] Di- and polyfunctional compounds having carbodiimide groups which are advantageously used in the compositions according to the invention are poly(cyclooctylenecarbodiimide), poly(1,4-dimethylenecyclohexylenecarbodiimide), poly(cyclohexylenecarbodiimide), poly(ethylenecarbodiimide), poly(butylenecarbodiimide), poly(isobutylenecarbodiimide), poly(nonylenecarbodiimide), poly(dodecylenecarbodiimide), poly(neopentylenecarbodiimide), poly(1,4-dimethylenephenylenecarbodiimide), poly(2,2',6,6'-tetraisopropyldiphenylenecarbodiimide) (Stabaxol® D), poly(2,4,6-triisopropyl-1,3-phenylenecarbodiimide) (Stabaxol® P-100), poly(2,6-diisopropyl-1,3-phenylenecarbodiimide) (Stabaxol® P-2 ... phenylenecarbodiimide) (Stabaxol® P), poly(tolylcarbodiimide), poly(4,4'-diphenylmethanecarbodiimide), poly(3,3'-dimethyl-4,4'-biphenylenecarbodiimide), poly(p-phenylenecarbodiimide), poly(m-phenylenecarbodiimide), poly(3,3'-dimethyl-4,4'-diphenylmethanecarbodiimide), poly(naphthylenecarbodiimide), poly(isophoronecarbodiimide), poly(cumenecarbodiimide), p-phenylenebis(ethylcarbodiimide), 1,6-hexamethylenebis(ethylcarbodiimide), 1,8-octamethylenebis(ethylcarbodiimide), 1,10-decamethylenebis(ethylcarbodiimide), 1,12-dodecamethylenebis(ethylcarbodiimide) and mixtures thereof.

[0050] Examples of di- and polyfunctional compounds carrying epoxide groups which may advantageously be used in the compositions according to the invention are epoxidized oils and / or all polyepoxides from styrene-glycidyl ether-methyl methacrylate, glycidyl ether-methyl methacrylate, with a molecular weight in the range of 1000 to 10000 and with a number of epoxides per molecule in the range of 1 to 30, preferably 5 to 25, as well as diethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, polyglycerol polyglycidyl ether, 1,2-epoxybutanoic acid esters, glycidyl ether-methyl methacrylate ... The epoxide is selected from the group consisting of cycloaliphatic diepoxides, 1,4-cyclohexanedimethanol diglycidyl ether, glycidyl 2-methylphenyl ether, glycerol propoxylate triglycidyl ether, 1,4-butanediol diglycidyl ether, sorbitol polyglycidyl ether, glycerol diglycidyl ether, tetraglycidyl ether of meta-xylylene diamine and diglycidyl ether of bisphenol-A, and mixtures thereof.

[0051] In one particularly preferred embodiment of the invention, the crosslinker and / or chain extender of the composition comprises a compound having an isocyanate group, preferably 4,4-diphenylmethane diisocyanate, and / or a compound having a carbodiimide group, and / or a compound having an epoxide group, preferably a compound of the styrene-glycidyl ether-methyl methacrylate type. In one particularly preferred embodiment of the invention, the crosslinker and / or chain extender comprises a compound having epoxide groups of the styrene-glycidyl ether-methyl methacrylate type.

[0052] With the isocyanates, peroxides, carbodiimides, isocyanurates, oxazolines, epoxides, anhydrides, di- and polyfunctional compounds bearing divinyl ether groups of the composition according to the invention, catalysts may be used to increase the reactivity of the reactive groups. In the case of polyepoxides, preferably fatty acid salts are used, even more preferably calcium stearate and zinc stearate.

[0053] The inorganic fillers (component iv) and the crosslinkers and / or chain extenders (component v) may be added in the desired final concentration directly or as a "masterbatch" in the hopper during the extrusion process. By "masterbatch" in the present invention is meant pellets based on aliphatic-aromatic polyesters (component ii) or based on lactic acid polyesters (component iii) containing high concentrations of crosslinkers and / or chain extenders or inorganic fillers. The concentration of additives in the masterbatch is usually between 10% and 15%. For example, Joncryl ADR4368CS containing 10% by weight of styrene-glycidyl ether-methyl methacrylate copolymer (component v) and 90% by weight of lactic acid polyesters (component iii) is used in masterbatch mode.

[0054] The composition according to the invention may contain an antifogging agent selected from esters of polyfunctional alcohols, preferably from condensation products of polyfunctional alcohols with fatty acids, said antifogging agent being present in an amount between 0.2 and 5% by weight, preferably between 1 and 3% by weight, relative to the total weight of the composition. The antifogging agent is preferably selected from esters of fatty acids having from 8 to 18 carbon atoms, more preferably from 12 to 16 carbon atoms. Suitable compounds that may be used as antifogging agents are polyglyceryl laurate, sorbitan monooleate, sorbitan trioleate and glycerin monopalmitate.

[0055] The composition according to the present invention preferably also contains at least one other component selected from the group consisting of plasticizers, UV stabilizers, lubricants, nucleating agents, surfactants, antistatic agents, pigments, flame retardants, compatibilizers, lignin, organic acids, antioxidants, fungicides, waxes, processing aids and polymeric components (preferably polymeric components selected from the group consisting of vinyl polymers, diacid diol polyesters that are not polyesters i and ii, polyamides, polyurethanes, polyureas, polycarbonates).

[0056] With regard to the plasticizer, the composition according to the invention preferably comprises a C4-C phthalate selected from the group consisting of phthalates, e.g. diisononyl phthalate, trimellitates, e.g. n-octanol and n-decanol. 20 and one or more plasticizers selected from the group consisting of trimellitic esters with monoalcohols, and aliphatic esters having the structure: R1-OC(O)-R4-C(O)-[-O-R2-OC(O)-R5-C(O)-] m -O-R3 During the ceremony R1 is H, C1~C 24 Linear and branched, saturated and unsaturated alkyl residues of the type C1-C 24 a polyol residue esterified with a monocarboxylic acid; R2 comprises -CH2-C(CH3)2-CH2- and alkylene C2-C8 groups and consists of at least 50 mol % of said -CH2-C(CH3)2-CH2- groups; R3 is H, C1~C 24 Linear and branched, saturated and unsaturated alkyl residues of the type C1-C 24 a polyol residue esterified with a monocarboxylic acid; R4 and R5 are the same or different and are C2-C 22 , preferably C2-C 11 , more preferably comprising one or more of C4-C9 alkylenes, and at least 50 mol % of C7 alkylenes; m is a number between 1 and 20, preferably between 2 and 10, more preferably between 3 and 7. Preferably, in said ester, at least one of the R1 and / or R3 groups is at least one C1-C stearic acid selected from the group consisting of stearic acid, palmitic acid, 9-ketostearic acid, 10-ketostearic acid and mixtures thereof. 24 The polyol residues esterified with monocarboxylic acids are preferably present in an amount of at least 10 mol %, more preferably at least 20 mol %, even more preferably at least 25 mol %, based on the total amount of R1 and / or R3 groups. Examples of such aliphatic esters are described in Italian patent application MI2014A000030 and PCT applications PCT / EP2015 / 050336, PCT / EP2015 / 050338.

[0057] If present, the selected plasticizer is preferably present in an amount of up to 5% by weight, based on the total weight of the composition.

[0058] Preferably, the lubricant is chosen from esters and metal salts of fatty acids, such as zinc stearate, calcium stearate, aluminium stearate and acetyl stearate. Preferably, the composition according to the invention comprises up to 1% by weight, more preferably up to 0.5% by weight, of a lubricant relative to the total weight of the composition.

[0059] Examples of nucleating agents include sodium saccharin, calcium silicate, sodium benzoate, calcium titanate, boron nitride, isotactic polypropylene, low molecular weight PLA. These additives are preferably added in an amount of up to 10% by weight, more preferably 5% by weight, based on the total weight of the composition.

[0060] Pigments such as titanium dioxide, clay, copper phthalocyanine, silicates, iron oxides and hydroxides, carbon black, and magnesium oxide may be added if desired. Preferred vinyl polymers include polyethylene, polypropylene, copolymers thereof, polyvinyl alcohol, polyvinyl acetate, polyethyl ethyl vinyl acetate and polyethylene vinyl alcohol, polystyrene, vinyl chloride polymers, polyacrylates.

[0061] The polyamides of the composition according to the invention are preferably selected from the group consisting of polyamides 6 and 6,6, polyamides 9 and 9,9, polyamides 10 and 10,10, polyamides 11 and 11,11, polyamides 12 and 12,12, and combinations thereof of the types 6 / 9, 6 / 10, 6 / 11, 6 / 12, mixtures thereof, and both random and block copolymers.

[0062] Preferably, the polycarbonate of the composition according to the invention is selected from the group consisting of polyalkylene carbonates, more preferably polyethylene carbonate, polypropylene carbonate, polybutylene carbonate, mixtures thereof, and both random and block copolymers.

[0063] Among the polyethers, preferred are those selected from the group consisting of polyethylene glycol, polypropylene glycol, polybutylene glycol, copolymers thereof and mixtures thereof, each having a molecular weight of 2,000 to 100,000, preferably 5,000 to 50,000.

[0064] The compositions according to the invention are highly suitable for use in a number of practical applications for the manufacture of products such as films, preferably blown films, and multi-layer films, and also for the manufacture of various packaging materials, in particular said multi-layer films into bags for transporting goods and bags for packaging food, such as fruit and vegetable bags. The composition according to the invention may be advantageously used in a cast extrusion process. The films made with the composition according to the invention advantageously have a thickness between 12 and 50 μm, preferably less than or equal to 40 μm and more preferably less than or equal to 30 μm.

[0065] The monolayer film has an optical haze property of 20% or less, preferably 15% or less, and a clarity of 90% or more, preferably 95% or more, measured according to the ASTM D1003 standard on a 30 μm thick film.

[0066] The multilayer film which is a further object of the present invention comprises at least one layer A, one layer B and / or one layer C, preferably characterized by an arrangement selected from A / B, A / C / B and A / C / A. The multilayer film has an optical haze property of 35% or less, preferably 25% or less, and a clarity of 70% or more, preferably 90% or more, as measured according to ASTM D1003 on a 40 micron thick film.

[0067] As far as the mechanical properties are concerned, within the meaning of the present invention, they are determined according to ASTM D882 (tensile strength at 23° C. and 55% relative humidity and v0=50 mm / min) in the longitudinal direction relative to the film formation direction. The film, whether monolayer or multilayer, is characterized by a Young's modulus of 600 Mpa or more, preferably 800 Mpa or more, even more preferably 1100 Mpa or more, and 4000 Mpa or less, preferably 3500 Mpa or less, even more preferably 3200 Mpa or less. Both monolayer and multilayer films obtained according to the invention advantageously have a modulus of elasticity of 200 g / m2, measured according to ASTM F1249 at 23° C. and 85% RH for a 30 μm thick film. 2 / day or less, preferably 150g / m 2 It shows a WVTR (water vapor transmission rate) value of less than 1 / day.

[0068] The multilayer film according to the invention has the following structure and composition: Layer A Layer A is composed of the above components i to v.

[0069] Layer B Layer B comprises at least one aliphatic polyester and at least one aliphatic-aromatic polyester as follows: vi) 40 to 70% by weight, preferably 55 to 65% by weight, based on the total weight of components vi to ix, of at least one aliphatic-aromatic polyester, e) based on the total dicarboxylic acid component, e1) 42 to 60 mol %, preferably 45 to 49.5 mol %, of units derived from at least one aromatic dicarboxylic acid; e2) 58 to 40 mol %, preferably 55 to 50.5 mol %, of units derived from at least one saturated aliphatic dicarboxylic acid; A dicarboxylic acid component comprising: f) based on the total diol content: f1) 95 to 100 mol % of units derived from at least one saturated aliphatic diol; f2) 0 to 5 mol % of units derived from at least one unsaturated aliphatic diol; Diol component containing aliphatic-aromatic polyesters, including; vii) 30 to 60% by weight, preferably 35 to 45% by weight, based on the total weight of components vi to ix, of at least one aliphatic polyester: g) g1) 55 to 85 mol % of units derived from succinic acid; g2) 15 to 45 mol % of units derived from at least one saturated dicarboxylic acid having a carbon atom number greater than 4 A saturated dicarboxylic acid component comprising: h) the total diol component, h1) 95 to 100 mol % of units derived from 1,4-butanediol; h2) 0 to 5 mol % of units derived from at least one saturated aliphatic diol other than 1,4-butanediol; Diol component containing aliphatic polyesters including; viii) 0-20% by weight of at least one polyhydroxyalkanoate; ix) 0 to 2.5% by weight, preferably 0.02 to 1.5% by weight, more preferably 0.1 to 1.0% by weight, based on the sum of components vi to ix, of at least one crosslinker and / or chain extender comprising at least one difunctional and / or polyfunctional compound having groups selected from isocyanates, peroxides, carbodiimides, isocyanurates, oxazolines, epoxides, anhydrides, divinyl ethers and mixtures thereof.

[0070] As far as the aliphatic-aromatic polyesters vi are concerned, they are defined similarly to the aliphatic-aromatic polyesters ii.

[0071] The aliphatic polyester vii is present in an amount of 30 to 60% by weight, preferably 35 to 45% by weight, based on the sum of vi to ix. The aliphatic polyester vii comprises a dicarboxylic acid component containing 55 to 85% by weight, preferably 60 to 75% by weight, based on the total dicarboxylic acid component, of units derived from succinic acid (component g1), and 15 to 45% by weight, preferably 25 to 40% by weight, of units derived from at least one saturated dicarboxylic acid having a carbon atom number greater than 4 (component g2).

[0072] Preferably, the saturated aliphatic dicarboxylic acid other than succinic acid of the aliphatic polyester vii is preferably a C5 to C 13 , preferably C5 to C 11 Saturated dicarboxylic acids, their C1-C 24 Preferably, the saturated aliphatic dicarboxylic acid other than succinic acid is selected from glutaric acid, 2-methylglutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, undecanedioic acid, dodecanedioic acid, brassylic acid and their C1-C alkyl esters, salts thereof and mixtures thereof. 24 In one preferred embodiment of the present invention, the saturated aliphatic dicarboxylic acid other than succinic acid is selected from the group consisting of adipic acid, azelaic acid, sebacic acid or mixtures thereof. In one even more preferred embodiment of the present invention, the saturated aliphatic dicarboxylic acid other than succinic acid is azelaic acid.

[0073] The dicarboxylic acid component of the aliphatic polyester vii may contain up to 5% of an unsaturated aliphatic dicarboxylic acid, preferably itaconic acid, fumaric acid, 4-methylene-pimelic acid, 3,4-bis(methylene)nonanedioic acid, 5-methylene-nonanedioic acid, their C1-C 24 In one preferred embodiment of the present invention, the unsaturated aliphatic dicarboxylic acid is at least 50 mol %, preferably 60 mol % or more, more preferably 65 mol % or more of itaconic acid or its C1-C4 alkyl esters, salts thereof and mixtures thereof. 24 , preferably a mixture comprising C1-C4 esters. More preferably, the unsaturated aliphatic dicarboxylic acid comprises itaconic acid.

[0074] The diol component of the aliphatic-aromatic polyester vii contains 95 to 100 mol %, preferably 97 to 100 mol %, of units derived from 1,4-butanediol (component h1), based on the total diol component, and 0 to 5 mol %, preferably 0 to 3 mol %, of units derived from at least one saturated aliphatic diol other than 1,4-butanediol (component h2), based on the total diol component.

[0075] The saturated aliphatic diol of the aliphatic polyester vii is preferably selected from the group consisting of 1,2 ethanediol, 1,2-propanediol, 1,3-propanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,11-undecanediol, 1,12-dodecanediol, 1,13-tridecanediol, 1,4-cyclohexanedimethanol, neopentyl glycol, 2-methyl-1,3-propanediol, dianhydrosorbitol, dianhydromannitol, dianhydroiditol, cyclohexanediol, cyclohexanemethanediol, dialkylene glycols and polyalkylene glycols having a molecular weight of 100 to 4000, such as polyethylene glycol, polypropylene glycol, and mixtures thereof.

[0076] The diol component of the aliphatic polyester vii may contain up to 5% of an unsaturated aliphatic diol, which is preferably selected from the group consisting of cis 2-butene-1,4-diol, trans 2-butene-1,4-diol, 2-butyne-1,4-diol, cis 2-pentene-1,5-diol, trans 2-pentene-1,5-diol, 2-pentyne-1,5-diol, cis 2-hexene-1,6-diol, trans 2-hexene-1,6-diol, 2-hexyne-1,6-diol, cis 3-hexene-1,6-diol, trans 3-hexene-1,6-diol, 3-hexene-1,6-diol.

[0077] In one particularly preferred embodiment, the aliphatic polyester vii is selected from the group consisting of poly(1,4-butylene succinate-co-adipate), poly(1,4-butylene succinate-co-1,4-butylene azelate), poly(1,4-butylene succinate-co-1,4-butylene sebacate). In one even more preferred embodiment, the aliphatic polyester vii is poly(1,4-butylene succinate-co-1,4-butylene azelate).

[0078] In the process of preparing the aliphatic polyesters vii, one or more polyfunctional molecules may advantageously be added in an amount between 0.1 and 3 moles relative to the total moles of the dicarboxylic acid component (as well as any hydroxy acid) in order to obtain branched products. Examples of these molecules are glycerol, pentaerythritol, trimethylolpropane, citric acid, dipentaerythritol, monoanhydrosorbitol, monohydromannitol, acid triglycerides, and polyglycerols.

[0079] The molecular weight Mn of the aliphatic polyester vii is preferably greater than or equal to 20 000, more preferably greater than or equal to 40 000. As regards the molecular weight polydispersity index Mw / Mn, this is preferably between 1.5 and 10, more preferably between 1.6 and 5, even more preferably between 1.8 and 3.5. Molecular weight M n and M w may be measured using gel permeation chromatography (GPC). Measurements may be performed on a chromatography system maintained at 40° C. using a set of two columns in series (mixed porosity of 5 μm and 3 μm particle sizes), a refractive index detector, chloroform as eluent (flow rate 0.5 ml / min) and polystyrene as reference standard.

[0080] The melt flow rate (MFR) of the aliphatic polyester vii is preferably between 500 and 1 g / 10 min, more preferably between 100 and 3 g / 10 min, and even more preferably between 15 and 4 g / 10 min (measurement is carried out at 190° C. / 2.16 kg according to ISO 1133-1 “Plastics-determination of the melt mass-flow rate (MFR) and melt volume flow rate (MVR) of thermoplastics-Part 1: Standard method”).

[0081] The terminal acid group content of the aliphatic polyester vii is preferably between 15 and 160 meq / kg, more preferably between 30 and 100 meq / kg, and even more preferably between 40 and 60 meq / kg. The acid end group content may be measured as follows: 1.5-3 g of polyester is placed in a 100 ml conical flask with 60 ml of chloroform. After the polyester is completely dissolved, 25 ml of 2-propanol is added, and immediately before analysis, 1 ml of deionized water is added. The resulting solution is titrated with a prestandardized ethanolic solution of NaOH. The equivalence point of the titration is determined using a suitable indicator, for example, a glass electrode for acid-base titrations in non-aqueous solvents. The acid end group content is calculated based on the consumption of the ethanolic NaOH solution according to the following formula:

number

[0082] Preferably, the aliphatic polyester vii has an intrinsic viscosity (measured with an Ubbelohde viscometer for a solution in CHCl3 at a concentration of 0.2 g / dl at 25°C) greater than 0.3 dl / g, preferably between 0.3 and 2 dl / g, more preferably between 0.4 and 1.3 dl / g.

[0083] The polyhydroxyalkanoate viii is preferably selected from the group consisting of lactic acid polyester, polyhydroxybutyrate, polyhydroxybutyrate-valerate, polyhydroxybutyrate-propanoate, polyhydroxybutyrate-hexanoate, polyhydroxybutyrate-decanoate, polyhydroxybutyrate, polyhydroxybutyrate, polyhydroxybutyrate, poly3-hydroxybutyrate-4-hydroxybutyrate and mixtures thereof, said polyhydroxyalkanoate viii being present in an amount of 0-20% by weight of the sum of components vi-ix.

[0084] In one preferred embodiment, the lactic acid polyester is selected from the group consisting of poly-L-lactic acid, poly-D-lactic acid, poly-DL-lactic acid stereocomplex, copolymers containing 50 mol % or more of the lactic acid polyester, and mixtures thereof.

[0085] Particularly preferred is a lactic acid copolymer that contains at least 95% by weight of repeating units derived from L-lactic acid or D-lactic acid or a combination thereof, has a molecular weight Mw of 50,000 or more, and has a shear viscosity of 50 to 700 Pa.s, preferably 80 to 500 Pa.s (T=190°C, shear rate=1000 S). -1 , D=1 mm, L / D=10, measured according to ASTM D3835 standard).

[0086] In one particularly preferred embodiment, the lactic acid polyester comprises at least 95% by weight of units derived from L-lactic acid, ≦5% by weight of repeating units derived from D-lactic acid, and has a melting temperature in the range of 135-175° C., a glass transition temperature (Tg) in the range of 55-65° C., and a MFR in the range of 1-50 g / 10 min (measured according to ISO standard 1133-1 at 190° C. and 2.16 kg). Commercially available examples of lactic acid polyesters having such properties are available from Ingeo, Inc. TM Biopolymer 4043D and 3251D.

[0087] With respect to the crosslinker and / or chain extender ix, this component is defined similarly to component v.

[0088] Layer C As for layer C, it comprises at least one polyester which may be an aliphatic polyester (component x) or an aliphatic-aromatic polyester (component xi) or a mixture thereof. As for the aliphatic polyesters x, these preferably contain a dicarboxylic acid component containing 60 to 100 mol %, preferably 90 to 95 mol %, of units derived from succinic acid, and 0 to 40 mol %, preferably 5 to 10 mol %, of units derived from at least one saturated dicarboxylic acid other than succinic acid, based on the total dicarboxylic acid components.

[0089] Preferably, the saturated aliphatic dicarboxylic acid other than succinic acid of the aliphatic polyester x of the composition according to the present invention is preferably a saturated C5-C 13 , preferably C5 to C 11 dicarboxylic acids, their C1-C 24 Preferably, the saturated aliphatic dicarboxylic acid other than succinic acid is selected from glutaric acid, 2-methylglutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, undecanedioic acid, dodecanedioic acid, brassylic acid and their C1-C alkyl esters, salts thereof and mixtures thereof. 24 In one preferred embodiment, the saturated aliphatic dicarboxylic acid other than succinic acid is selected from the group consisting of adipic acid, azelaic acid, sebacic acid or mixtures thereof. In one even more preferred embodiment, the saturated aliphatic dicarboxylic acid other than succinic acid is azelaic acid.

[0090] As far as the aliphatic-aromatic polyesters xi are concerned, preferably they can be defined similarly to the aliphatic-aromatic polyesters ii. Preferably, layer C comprises an aliphatic polyester (component x).

[0091] Readily compostable under home composting conditions means 90% or more disintegration within 180 days according to UNI 11355 Appendix A (Test Method). Ready biodegradable in the marine environment means at least 60% biodegradation within 400 days as measured in accordance with ISO 19679. What is particularly surprising is that marine biodegradation occurs at high percentages of polylactic acid, whereas PLA is known to resist biodegradation under these conditions.

[0092] The multilayer film can achieve good weldability even at low temperatures. Good weldability is achieved according to ASTM F88 (Technique A, 300 mm / min, specimen width 25.4 mm) for a welding time of 1 second and a high holding strength of 350 N at 15 cm 2 It is defined as a weld strength of 12N or greater measured in a weld between B layers (inner / inner contact) made at 85°C using a Teflon-coated welding rod of 1.0 mm.

[0093] The compositions according to the invention can also be applied to the manufacture of other types of articles such as fibers, nonwovens, foils, molded articles, thermoformed articles, blow molded articles, foam molded articles and laminates using extrusion coating techniques.

[0094] The present invention also relates to an article comprising a composition according to the invention. Examples of products comprising the composition according to the invention are: Both unidirectional and bidirectional films, as well as multilayer films containing other polymeric materials; -Fabrics for use in the agricultural sector as agricultural textile fabrics; - thermoformed food packaging, both in single and multi-layer form, e.g. containers for milk, yogurt, meat and beverages; -coatings obtained using extrusion coating technology; - multi-layer laminates having layers of paper, plastic, aluminum and metallized film; -Containers generally for fruit and vegetables; - fibres, microfibres, composite fibres with a core made of hard polymers, e.g. PLA, PET, PTT etc. and an outer shell made of the material according to the invention, dablens composite fibres, fibres with different cross sections from round to multilobed, staple fibres, woven and nonwoven fabrics or spun-bonded or thermobonded fabrics for the health, hygiene, agriculture and clothing sectors.

[0095] The invention will now be described using examples of some embodiments, which are intended to be illustrative rather than limiting the scope of protection of the present patent application. EXAMPLES

[0096] Component I i = Poly(1,4-butylene succinate-co-1,4-butylene azelaic acid) ("PBSAz-1") prepared according to the following method: 14830 g succinic acid, 2625 g azelaic acid, 2650 g 1,4-butanediol, 25.7 g glycerin and 2.0 g diisopropyl triethanolamino titanate (Tyzor TE, containing 8.2 wt. % titanium) in an 80 wt. % ethanol solution with a diol / dicarboxylic acid molar ratio (MGR) of 1.07 were charged into a steel reactor with a geometric volume of 60 liters, equipped with a mechanical stirring system, a nitrogen inlet, a distillation column, a high-boiling distillate removal system and a connection to a high vacuum system. The temperature of the mass was gradually increased to 230°C over 120 minutes. When 95% of the theoretical water was distilled off, 21.25 g of tetra n-butyl titanate was added (corresponding to 119 ppm metal relative to the amount of poly(1,4-butylene succinate-co-1,4-butylene azelate) that could theoretically be obtained by converting all the succinic and azelaic acids fed to the reactor). The temperature of the reactor was then increased to 235-240°C and the pressure was gradually reduced to below 2 mbar over 60 minutes. The reaction was allowed to proceed for the time necessary to obtain poly(1,4-butylene succinate-co-1,4-butylene azelate) with an MFR of about 7 (g / 10 min at 190°C and 2.16 kg), and the material was then discharged as strands into a water bath and granulated.

[0097] Component II ii = Poly(1,4-butylene adipate-co-1,4-butylene terephthalate) ("PBAT") prepared according to the following method: 7453 g of terephthalic acid, 7388 g of adipic acid, 12033 g of 1,4-butanediol, 4.4 g of glycerol and 3.4 g of diisopropyl triethanolamino titanate (Tyzor TE, containing 8.2 wt. % titanium) in an 80 wt. % ethanol solution with a diol to dicarboxylic acid molar ratio (MGR) of 1.40 were charged into a steel reactor with a geometric volume of 60 liters, equipped with a mechanical stirring system, a nitrogen inlet, a distillation column, a high-boiling distillate removal system and a connection to a high vacuum system. The temperature of the mass was gradually increased to 230°C over 120 minutes. When 95% of the theoretical water was distilled off, 17.0 g of tetra n-butyl titanate was added (corresponding to 119 ppm metal relative to the amount of poly(1,4-butylene adipate-co-1,4-butylene terephthalate) that could theoretically be obtained by converting all the adipic and terephthalic acids fed to the reactor). The temperature of the reactor was then increased to 235-240°C and the pressure was gradually reduced to below 2 mbar over 60 minutes. The reaction was allowed to proceed for the time necessary to obtain poly(1,4-butylene adipate-co-1,4-butylene terephthalate) with an MFR of about 6 (g / 10 min at 190°C and 2.16 kg), and the material was then discharged as strands into a water bath and granulated.

[0098] ingredient iii iii-1 = Polylactic acid ("PLA") Ingeo 3251D, MFR 36 / 10 min (at 190°C, 2.16 Kg) and shear viscosity 145 Pa.s (ASTM D3835, T = 190°C, shear rate = 1000 s -1 , D=1mm, L / D=10) iii-2 = Polylactic acid ("PLA") Ingeo 4043D, MFR 3 / 10 min (at 190°C, 2.16 Kg) and shear viscosity 360 Pa.s (ASTM D3835, T = 190°C, shear rate = 1000 s -1 , D=1mm, L / D=10)

[0099] ingredient vi vi=ingredient ii

[0100] ingredient vii vii=Poly(1,4-butylene succinate-co-1,4-butylene azelaic acid) ("PBSAz-2") prepared according to the following method: 9760 g succinic acid, 8370 g azelaic acid, 12250 g 1,4-butanediol, 23.4 g glycerin and 2.0 g diisopropyl triethanolamino titanate (Tyzor TE, containing 8.2 wt. % titanium) in an 80 wt. % ethanol solution with a diol / dicarboxylic acid molar ratio (MGR) of 1.07 were charged into a steel reactor with a geometric volume of 60 liters, equipped with a mechanical stirring system, a nitrogen inlet, a distillation column, a high-boiling distillate removal system and a connection to a high vacuum system. The temperature of the mass was gradually increased to 230°C over 120 minutes. When 95% of the theoretical water was distilled off, 21.25 g of tetra n-butyl titanate was added (corresponding to 119 ppm metal relative to the amount of poly(1,4-butylene succinate-co-1,4-butylene azelate) that could theoretically be obtained by converting all the succinic and azelaic acids fed to the reactor). The temperature of the reactor was then increased to 235-240°C and the pressure was gradually reduced to below 2 mbar over 60 minutes. The reaction was allowed to proceed for the time necessary to obtain poly(1,4-butylene succinate-co-1,4-butylene azelate) with an MFR of about 7.6 (g / 10 min at 190°C and 2.16 kg), and the material was then discharged as strands into a water bath and granulated.

[0101] ingredient x x=component i

[0102] Ingredient xi xi=component ii

[0103] Masterbatch m-1 = a masterbatch comprising 15 wt.% of silica (component iv) and 85 wt.% of component ii. m-2 = Masterbatch containing 10 wt% Joncryl ADR4368CS (component v) and 90 wt% component iii-1. m-3 = Masterbatch containing 10 wt% Joncryl ADR4368CS (component ix) and 90 wt% polylactic acid Ingeo 3251D (component viii).

[0104] The compositions shown in Table 1 were fed into a co-rotating twin screw extruder model OMC EBV60 / 36 (L / D=36; diameter 58 mm) operating under the following conditions:

[0105] -rpm: 140 -Flow rate: 40kg / h -Thermal profile: 60-150-180-210x4-150x2°C -4 zone vacuum degassing

[0106] The obtained compound granules of Examples 1-4 and Comparative Examples 1-5 were fed at a flow rate of 26 kg / h to a Ghioldi model blown film machine with a screw diameter of 40 mm and L / D 30, operating at 64 rpm with a thermal profile of 120-170-210 x 7°C. The film forming head with an air gap of 0.9 mm and L / D 12 was set at 180°C. Films were formed with a blow ratio of 3.2 and a stretch ratio of 14.5. The resulting film thickness was 30 μm.

[0107] The optical properties were determined according to ASTM standard D1003, see Table 2.

[0108] Mechanical properties were determined according to ASTM D882 (tensile strength at 23° C. and 55% relative humidity and vo=50 mm / min), see Table 3. [Table 1]

[0109] Example 5 - Bilayer film in A / B configuration Preparation of Example 6 (Layer B): A composition containing 58.5% of component vi, 39% of component vii and 2.5% of masterbatch m-3 was fed into a co-rotating twin screw extruder model OMC EBV60 / 36 (L / D=36; diameter 58 mm) operating under the same conditions as in Examples 1-4.

[0110] The compound granules of Example 1 (Table 1) and Example 6 were fed simultaneously into a co-extruder to form a two-layer blown film with an A / B configuration. The compound granules of Example 1 (Layer A) were fed through two extruders. The first extruder was characterized by a screw diameter of 40 mm with a L / D30 operating at 35 rpm with a heat profile of 60-170-200 x 3 at a flow rate of 18.0 kg / h, and the second extruder was characterized by a screw diameter of 35 mm with a L / D30 operating at 24 rpm with a heat profile of 60-170-200 x 3 at a flow rate of 6.0 kg / h.

[0111] In parallel, the compound granules of Example 6 (Layer B) were fed at 6.0 kg / h to an extruder operating at 30 rpm with a heat profile of 60-135-145 x 3, with a screw diameter of 35 mm and L / D 30. After melting, the compositions were combined in a coextrusion blow head set at 200°C, with an air gap of 0.9 mm and L / D 9, and the multilayer structure was fed to a film forming process operating at a blow ratio of 3.2 and a stretch ratio of 7. The resulting films (40 microns total thickness, 80% layer B) were then characterized for optical (Table 2), mechanical (Table 3) and disintegration properties (Table 5).

[0112] Example 7 - Three-layer film in A / C / B configuration The compound granules of Example 1 (Table 1, layer A), component xi (layer C) and the compound granules of Example 6 (layer B) were simultaneously fed into a co-extruder to form a three-layer blown film with an A / C / B configuration. For this purpose, the compound granules of Example 1 were fed at a rate of 15.0 kg / h to a first extruder having a screw diameter of 35 mm and L / D30 operating at 63 rpm with a thermal profile of 60-170-200x3, component xi was fed at a rate of 9.0 kg / h to a second extruder characterized by a screw diameter of 40 mm and L / D30 operating at 32 rpm with a thermal profile of 60-135-160x3, and compound granules of Example 6 were fed at a rate of 6.0 kg / h to an extruder having a screw diameter of 35 mm and L / D30 operating at 25 rpm with a thermal profile of 60-135-145x3.

[0113] Once melted, the compositions were combined in a coextrusion blow head set at 200°C with an air gap of 0.9 mm and L / D of 9, and the multi-layer structure was fed into a film forming process operating at a blow ratio of 3.2 and a stretch ratio of 7. The resulting film (40 microns total thickness, 50% layer A, 30% layer C, 20% layer B) was then characterized for optical (Table 2), mechanical (Table 3) and disintegration properties (Table 5).

[0114] Example 8 - Three-layer film in A / C / B configuration The compound granules of Example 1 (Table 1, layer A), component x (layer C) and compound granules of Example 6 (layer B) were fed simultaneously into a co-extruder to form a three-layer blown film with an A / C / B configuration. For this purpose, the compound granules of Example 1 were fed at a rate of 15.0 kg / h into a first extruder with a screw diameter of 35 mm and L / D30 operating at 58 rpm with a thermal profile of 60-170-200x3, component x was fed at a rate of 9.0 kg / h into a second extruder characterized by a screw diameter of 40 mm and L / D30 operating at 26 rpm with a thermal profile of 60-135-160x3, and compound granules of Example 6 were fed at a rate of 6.0 kg / h into an extruder with a screw diameter of 35 mm and L / D30 operating at 25 rpm with a thermal profile of 60-135-145x3. Once melted, the compositions were combined in a coextrusion blow head set at 200°C with an air gap of 0.9 mm and L / D of 9, and the multi-layer structure was fed into a film forming process operating at a blow ratio of 3.2 and a stretch ratio of 7. The resulting film (40 microns total thickness, 50% layer A, 30% layer C, 20% layer B) was then characterized for optical (Table 2), mechanical (Table 3) and disintegration properties (Table 5).

[0115] Example 9 - Three-layer film in A / C / A configuration The compound granules of Example 1 (Table 1, layer A) and component x (layer C) were fed simultaneously into a co-extruder to form a three-layer blown film with an A / C / A configuration. The compound granules of Example 1 were fed through two extruders. The first extruder was characterized by a screw diameter of 35 mm with a L / D30 running at 42 rpm with a thermal profile of 60-170-200x3 at a flow rate of 10.6 kg / h, and the second extruder was characterized by a screw diameter of 35 mm with a L / D30 running at 40 rpm with a thermal profile of 60-170-200x3 at a flow rate of 10.9 kg / h. In parallel, component x was fed at 8.8 kg / h to an extruder with a screw diameter of 40 mm and L / D 30 running at 24 rpm with a thermal profile of 60-135-170x3. Once melted, the compositions were combined in a coextrusion blow head set at 200°C with an air gap of 0.9 mm and L / D of 9, and the multi-layer structure was fed into a film forming process operating at a blow ratio of 3.2 and a stretch ratio of 7.

[0116] The resulting film (40 microns total thickness, 35% layer A, 30% layer C, 35% layer A) was then characterized for optical (Table 2), mechanical (Table 3) and disintegration properties (Table 5). [Table 2]

[0117] [Table 3]

[0118] [Table 4]

[0119] [Table 5]

Claims

1. A multilayer film comprising at least one layer A and one layer B and / or one layer C, preferably characterized by an arrangement selected from A / B, A / C / B and A / C / A, Layer A is: i) 10 to 49% by weight, preferably 14 to 45% by weight, more preferably 24 to 40% by weight, even more preferably 35 to 40% by weight, based on the sum of components i to v, of at least one aliphatic polyester i: a) Based on the total dicarboxylic acid components, the following: a1) 60 to 95 mol %, preferably 70 to 85 mol %, of units derived from succinic acid; a2) 5 to 40 mol %, preferably 15 to 30 mol %, of units derived from at least one saturated dicarboxylic acid having more than 4 carbon atoms; a dicarboxylic acid component comprising: b) Based on the total diol component, the following: b1) 95 to 100 mol % of units derived from 1,4-butanediol; b2) 0 to 5 mol % of units derived from at least one saturated aliphatic diol other than 1,4-butanediol; Diol component containing aliphatic polyester i comprising ii) 0 to 15% by weight, preferably 1 to 5% by weight, based on the sum of components i to v, of at least one aliphatic-aromatic polyester ii, c) the following based on the total dicarboxylic acid components: c1) 42 to 60 mol %, preferably 45 to 49.5 mol %, of units derived from at least one aromatic dicarboxylic acid; c2) 58 to 40 mol %, preferably 50.5 to 55 mol %, of units derived from at least one saturated aliphatic dicarboxylic acid; a dicarboxylic acid component comprising: d) The following based on the total diol component: d1) 95 to 100 mol % of units derived from at least one saturated aliphatic diol; d2) 0 to 5 mol % of units derived from at least one unsaturated aliphatic diol; Diol component containing aliphatic-aromatic polyesters comprising: iii) 51 to 90% by weight, preferably 55 to 86% by weight, more preferably 60 to 76% by weight, and even more preferably 60 to 65% by weight of at least one lactic acid polyester, based on the total of components i to v; iv) 0 to 1.5% by weight, preferably 0.1 to 0.2% by weight, more preferably 0.2 to 0.5% by weight, of at least one inorganic filler, based on the total of components i to v; v) 0 to 2.5% by weight, preferably 0.02 to 1.5% by weight, based on the sum of components i to v, of at least one crosslinker and / or chain extender, comprising at least one compound with bifunctional and / or polyfunctional groups, including groups selected from isocyanates, peroxides, carbodiimides, isocyanurates, oxazolines, epoxides, anhydrides, divinyl ethers and mixtures thereof; The polymeric composition comprises: Layer B is: vi) 40 to 70% by weight, preferably 55 to 65% by weight, based on the sum of components vi to ix, of at least one aliphatic-aromatic polyester, e) the following based on the total dicarboxylic acid component: e1) 42 to 60 mol % of units derived from aromatic dicarboxylic acids; e2) 40 to 58 mol % of units derived from at least one saturated aliphatic dicarboxylic acid; e3) 0 to 5 mol % of units derived from at least one unsaturated aliphatic dicarboxylic acid; a dicarboxylic acid component comprising: f) the total diol component: f1) 95 to 100 mol % of units derived from at least one saturated aliphatic diol; f2) 0 to 5 mol % of units derived from at least one unsaturated aliphatic diol; Diol component containing aliphatic-aromatic polyesters comprising: vii) 30 to 60% by weight, preferably 35 to 45% by weight, based on the sum of components vi to ix, of at least one aliphatic polyester, g) The following: g1) 55 to 85 mol % of units derived from succinic acid; g2) 15 to 45 mol % of units derived from saturated dicarboxylic acids having more than 4 carbon atoms a saturated dicarboxylic acid component comprising: h) The following based on the total diol component: h1) 95 to 100 mol % of units derived from 1,4-butanediol; h2) 0 to 5 mol % of units derived from at least one saturated aliphatic diol other than 1,4-butanediol; Diol component containing aliphatic polyesters comprising: viii) 0 to 20% by weight, based on the sum of components vi to ix, of at least one polyhydroxyalkanoate; ix) 0 to 2.5 wt. %, preferably 0.02 to 1.5 wt. %, more preferably 0.1 to 1.0 wt. %, based on the sum of components vi to ix, of at least one crosslinker and / or chain extender comprising at least one difunctional and / or polyfunctional compound having groups selected from isocyanates, peroxides, carbodiimides, isocyanurates, oxazolines, epoxides, anhydrides, divinyl ethers and mixtures thereof. at least one aliphatic polyester and at least one aliphatic-aromatic polyester, Layer C comprises at least one polyester which may be an aliphatic polyester (component x) or an aliphatic-aromatic polyester (component xi) or a mixture thereof; Multilayer film.

2. 2. The multilayer film of claim 1, wherein the saturated aliphatic dicarboxylic acid having more than 4 carbon atoms (component a2) of Layer A is selected from the group consisting of adipic acid, azelaic acid, sebacic acid, and mixtures thereof.

3. 3. The multilayer film of claim 2, wherein the saturated aliphatic dicarboxylic acid having more than four carbon atoms is azelaic acid.

4. 4. The multilayer film according to claim 1, wherein the aliphatic polyester i is selected from the group consisting of poly(1,4-butylene succinate-co-1,4-butylene adipate), poly(1,4-butylene succinate-co-1,4-butylene azelate), and poly(1,4-butylene succinate-co-1,4-butylene sebacate).

5. The aliphatic-aromatic polyester (component ii) is preferably poly(l,4-butylene adipate-co-1,4-butylene terephthalate), poly(l,4-butylene sebacate-co-1,4-butylene terephthalate), poly(l,4-butylene azelate-co-1,4-butylene terephthalate), poly(l,4-butylene brassylate-co-1,4-butylene terephthalate), poly(1,4-butylene succinate-co-1,4-butylene terephthalate), poly(1,4-butylene adipate-co-1,4-butylene sebacate-co-1,4-butylene terephthalate), poly(1,4-butylene azelate-co-1,4-butylene sebacate-co-1,4-butylene 4. The multilayer film of claim 1, wherein the copolymer is selected from the group consisting of poly(1,4-butylene adipate-co-1,4-butylene azelate-co-1,4-butylene terephthalate), poly(1,4-butylene succinate-co-1,4-butylene sebacate-co-1,4-butylene terephthalate), poly(1,4-butylene adipate-co-1,4-butylene succinate-co-1,4-butylene terephthalate), and poly(1,4-butylene azelate-co-1,4-butylene succinate-co-1,4-butylene terephthalate).

6. 4. The multilayer film according to claim 1, wherein the lactic acid polyester (component iii) comprises at least 95% by weight of repeating units derived from L-lactic acid or D-lactic acid or a combination thereof and has a molecular weight Mw of at least 50,000 and a shear viscosity of between 50 and 250 Pa*s, preferably between 80 and 200 Pa*s (measured according to ASTM standard D3835 at T = 190°C, shear rate = 1000 s-1, D = 1 mm, L / D = 10).

7. 2. The multilayer film according to claim 1, wherein the lactic acid polyester comprises at least 96% by weight of units derived from L-lactic acid and ≦4% by weight of units derived from D-lactic acid, and has a melting point in the range of 160 to 180°C, a glass transition temperature (Tg) in the range of 55 to 65°C, and an MFR of 10 to 50 g / 10 min (measured on a dry polymer (water content of 400 ppm or less) at 190°C and 2.16 kg according to ASTM-D1238 standard).

8. 4. The multilayer film of claim 1, wherein the inorganic filler (component iv) is selected from the group consisting of kaolin, barytes, clay, talc, calcium and magnesium carbonate, iron and lead carbonate, aluminum hydroxide, diatomaceous earth, aluminum sulfate, barium sulfate, silica, mica, titanium dioxide, and wollastonite.

9. 4. A multilayer film according to claim 1, wherein the inorganic filler (component iv) is selected from mica, calcium carbonate, silica and mixtures thereof and is present in the form of particles having an arithmetic mean diameter (measured according to ASTM 13320) measured along the major axis of the particle of less than or equal to 10 μm, more preferably less than or equal to 2 μm.

10. 4. The multilayer film according to claim 1, wherein the crosslinking agent and / or chain extender (component v) is selected from di- and / or polyfunctional groups selected from isocyanates, peroxides, carbodiimides, isocyanurates, oxazolines, epoxides, anhydrides, divinyl ethers, and combinations thereof.

11. 2. The multilayer film of claim 1, wherein the aliphatic polyester vi of Layer B is selected from the group consisting of poly(1,4-butylene succinate-co-1,4-butylene adipate), poly(1,4-butylene succinate-co-1,4-butylene azelate), and poly(1,4-butylene succinate-co-1,4-butylene sebacate).

12. The aliphatic-aromatic polyester (component vi) of Layer B is preferably selected from the group consisting of poly(1,4butylene adipate-co-1,4-butylene terephthalate), poly(1,4-butylene sebacate-co-1,4-butylene terephthalate), poly(1,4-butylene azelate-co-1,4-butylene terephthalate), poly(1,4-butylene brassylate-co-1,4-butylene terephthalate), poly(1,4-butylene succinate-co-1,4-butylene terephthalate), poly(1,4-butylene adipate-co-1,4-butylene sebacate-co-1,4-butylene terephthalate), poly(1,4-butylene azelate-co-1,4-butylene sebacate-co-1,4-butylene terephthalate), poly(1,4-butylene adipate-co-1,4-butylene azelate-co-1,4-butylene terephthalate), poly(1,4-butylene succinate-co-1,4-butylene sebacate-co-1,4-butylene terephthalate), poly(1,4-butylene adipate-co-1,4-butylene succinate-co-1,4-butylene terephthalate), poly(1,4-butylene azelate-co-1,4-butylene succinate-co-1,4-butylene terephthalate).

13. 4. A multilayer film according to claim 1, characterized in that it is biodegradable in a marine environment by at least 90% within 180 days according to UNI 11355 Annex A (test method) and by at least 60% within 400 days according to ISO 19679.