BIODEGRADABLE VCI PACKAGING COMPOSITIONS

Abstract

A breathable biodegradable volatile corrosion inhibitor polyester composition comprises one or more biodegradable homopolymeric polyesters and / or one or more biodegradable random copolymeric polyesters, one or more volatile corrosion inhibitors (VCIs), and one or more fillers, wherein said composition has a higher water vapor transmission rate than polyethylene.

Description

BIODEGRADABLE VCI PACKAGING COMPOSITIONS FIELD OF INVENTION A breathable, biodegradable volatile corrosion inhibitor composition comprises a biodegradable polyester composition comprising one or more homopolymeric polyesters and / or one or more random copolymeric polyesters with one or more volatile corrosion inhibitors (VCIs), and at least one or more fillers that unexpectedly enhance various physical properties of the composition. The total amount of said one or more VCIs is generally from approximately 0.1% to approximately 10% by weight based on the total weight of all biodegradable polyesters excluding said fillers. BACKGROUND OF THE INVENTION There is an urgent need for biodegradable compositions worldwide due to the ever-increasing amount of waste plastics and polymers being deposited in landfills, garbage pits, and municipal and government dumps, which often contaminate and / or release hazardous and / or toxic compounds into the water table. In oceans and seas, a growing amount of waste is proving to be a danger to fish and mammals that consume it and often die as a result, thus eliminating an important food source. Packaging is an integral part of corrosion protection, as environmental elements cause corrosion when they come into contact with metal parts. However, after shipment, the packaging, which is mostly made of thin LDPE and LLDPE films, needs to be disposed of, and many recycling facilities do not accept flexible packaging made of LDPE and LLDPE.Therefore, the packaging material ends up in landfills, etc. Given current consumer awareness, companies are increasingly pressured to reduce their plastic footprint, and one way to do this is to use biodegradable bags for metal packaging when the product's lifespan and other factors allow for the use of biodegradable material. U.S. Patent 6,028,160 to Cortee Corporation relates to biodegradable resin products consisting essentially of a polyethylene polymer resin, starch, polyesters such as polylactic acid or other suitable polyesters. Mixed with the resin is a particulate vapor-phase corrosion inhibitor selected from amine salts, ammonium benzoate, triazole derivatives, tall oil imidazolines, alkali metal molybdates, alkali dibasic acid salts, and mixtures thereof, and present in an amount ranging from 1% to 3% by weight of the polymer resin. U.S. Patent 6,156,929 to Cortee Corporation relates to biodegradable resin products consisting essentially of a starch polymer resin, polylactic acid polyesters, and polycaprolactone. Mixed with the resin is a particulate vapor-phase corrosion inhibitor selected from amine salts, ammonium benzoate, triazole derivatives, tall oil imidazolines, alkali metal molybdates, alkali dibasic acid salts, and mixtures thereof, and present in an amount ranging from 1% to 3% by weight of the polymer resin. U.S. Patent 6,617,415 to Cortee Corporation relates to biodegradable resin products consisting essentially of a starch polymer resin, polyesters such as polylactic acid or other suitable polyesters. Mixed with the resin is a particulate vapor-phase corrosion inhibitor selected from amine salts, triazole derivatives, alkaline dibasic acid salts, and mixtures thereof, present in an amount ranging from 1% to 3% by weight of the polymer resin and incorporated into formed articles. noRci η / ι ζπζ / ε / υιλι U.S. Patent 6,984,426 to Cortee Corporation relates to a biodegradable film conformable to biodegradable bags, comprising a blended product of polylactic acid and a suitable biodegradable polymer resin. The blended product includes approximately 5% to approximately 50% by weight of polylactic acid. Purac Biochem BV's U.S. Publication 2014 / 0235777 refers to a composition comprising a poly-D-lactic acid (PDLA) polymer and a poly-L-lactic acid (PLLA) polymer. It also refers to a method for producing a molded part comprising the steps of heating a mold and supplying the mold with a composition comprising a poly-D-lactic acid (PDLA) polymer and a poly-L-lactic acid (PLLA) polymer. It further refers to a composition comprising a poly-D-lactic acid (PDLA) polymer and a poly-L-lactic acid (PLLA) polymer for use in injection molding, thermoforming, and / or blow molding of films. It also refers to a composition obtainable by heating a composition comprising a poly-D-lactic acid (PDLA) polymer and a poly-L-lactic acid (PLLA) polymer. U.S. Patent 8,008,373 to Northern Technologies International Corporation relates to a biodegradable thermoplastic polymer stock blend composition comprising a blend of at least one biodegradable thermoplastic polymer containing a high loading of a particulate filler uniformly dispersed therein. The amount of the biodegradable thermoplastic polymer is generally about 25% to about 50% by weight, and the amount of the filler is about 75% to about 50% by weight, based on the total amount of the biodegradable polymer and the at least one filler. The uniform dispersion of the fillers is achieved by adding small particles of the filler to a melt of the biodegradable polymer and blending using high-shear equipment with a special screw geometry.The mastermix composition is then physically blended with an additional biodegradable thermoplastic polymer and processed by extrusion into finished products such as blown and melt-blown films, molded products, and the like. This multi-stage mastermix approach results in a product with improved physical properties and lower costs than a single-step blend of the same amount of a biodegradable thermoplastic polymer and a filler that is subsequently heat-formed into a finished product. BRIEF DESCRIPTION OF THE INVENTION One aspect of the present invention is to alleviate the aforementioned pollution and / or toxicity problems. Another aspect is to provide a composition in the form of a film that can exceed the EN 13432 and ASTM D6400 standards, which evaluate the compostability of materials in industrial composting facilities. The composition has superior mechanical properties and volatile corrosion inhibition properties compared to PE, unlike the products mentioned above, and can therefore effectively replace PE-based materials in the field of corrosion mitigation. Another important aspect of the present invention is to provide a biodegradable VCI packaging composition that effectively prevents corrosion of various items, including machinery, tools, and metal parts.Since water is one of the essential components for corrosion, it is commonly believed that lower water vapor transmission rates (WVTR) of a VCI packing composition, such as packing material containing a VCI, result in better corrosion inhibition. However, our results show that biodegradable compositions, such as biodegradable polyester plastic bags, perform better than polyethylene (PE) bags when containing the same amounts of VCIs, even though the WVTR of the biodegradable bags is higher than that of the PE bags.VCI chemicals, such as sodium nitrite, carboxylic acid salts, or ammonium salts, react with water to release the VCI, and therefore, if more moisture permeates through the bag more quickly, more VCI chemical is activated in a shorter period, and the chemical would reach the metal surface sooner than in a bag with a lower water vapor transmission rate. The VCI packaging compositions of the present invention containing fillers have improved breathability, shown increased water vapor transmission rates (WVTR), improved processability on extrusion equipment, shown less blocking, allowing bags made with this material to open more easily, lower cost without sacrificing the mechanical properties of the product, and better corrosion resistance than compositions containing the same amounts and types of VCI but without fillers. These and other aspects of the present invention are achieved by using a mixture of PLA and / or an aromatic aliphatic polyester copolymer with one or more VCI compounds and one or more fillers. A biodegradable volatile corrosion inhibitor polyester composition comprises one or more biodegradable random copolymer polyesters and / or one or more biodegradable homopolymer polyesters; from approximately 0.1% by weight to approximately 10% by weight of one or more volatile corrosion inhibitors based on 100 total parts by weight of said one or more biodegradable random copolymer polyesters and / or said one or more biodegradable homopolymer polyesters; and from approximately 3 to approximately 53 parts by weight of at least one filler based on 100 parts by weight of said one or more biodegradable random copolymer polyesters and / or said one or more biodegradable homopolymer polyesters. DETAILED DESCRIPTION OF THE INVENTION The present invention relates to biodegradable VCI compositions that are desirable for many uses, including the packaging of various articles, apparatus, machines, parts, and the like. Such articles are contained within, inserted into, wrapped around, or otherwise exist within the biodegradable VCI packaging compositions of the present invention. The packaging material is preferably in the form of a sheet or film that can be used to form a container, enclosure, or box for the aforementioned articles that are to be protected against corrosion. na^ci η / ι ζπζ / ε / υιλι An essential component of biodegradable VCI composition is one or more biodegradable homopolymeric polyesters or one or more random copolymeric polyesters, or both. The polymers that can be used as one or more homopolymeric polyesters include polylactide, polycaprolactone, a mixture of PLA and polycaprolactone, polyglycolide, or polyhydroxyalkanoates (PHAs), or any combination thereof. Ideally, these polymers should be relatively pure, meaning they contain no contaminants or other polymers. Specifically, they generally contain less than approximately 3% or approximately 1% by weight of any contaminant, ideally less than approximately 0.5% by weight, and preferably less than approximately 0.1% by weight or zero, meaning they contain no contaminants at all. Typical molecular weights of commercial polylactide homopolymers or other homopolymeric polyesters may be used, wherein the weight-average molecular weight thereof is approximately 100,000 to approximately 175,000, desirably approximately 110,000 to approximately 150,000, and preferably approximately 125,000 to approximately 140,000 g / mol. One or more polylactides differing in molecular weight and / or obtained from different manufacturers may be used. By way of example only, a suitable polylactide that may be used in the present invention is PLA 3052D, manufactured by Natureworks. In addition to, or instead of, one or more biodegradable homopolymeric polyesters, one or more random copolymeric polyesters such as a random aliphatic-aromatic copolyester or a random aliphatic copolyester may be used. The number and type of random copolyesters are large and they generally have the formula: where R1 independently comprises ..... where x, independently, is an integer from approximately 2 to approximately 10, or from approximately 34 (fatty acid dimer), where y, independently, is an integer from 2 to approximately 8. Ideally, -(CEbK- can be derived from an adipic acid, a sebacic acid or an azelaic acid, and (CH2)y- can be derived from 1,4-butanediol or ethylene glycol. The number of repeating units myn is such that the average molecular weight in total weight of the random copolymer is as shown below. Examples of suitable compostable random copolymer polyesters include polybutylene sebacate-co-terephthalate (PBST), with polybutylene adipate-co-terephthalate (PBAT) being preferred. The weight average molecular weight of one or more random copolymer polyesters, independently, can range from approximately 80,000 to approximately 175,000, with a desirable weight average molecular weight being approximately 90,000 to approximately 150,000, and preferably approximately 100,000 to approximately 130,000. The weight average molecular weight of the aforementioned polylactide homopolymeric polyesters, as well as the random copolymeric polyesters, was determined by gel permeation chromatography (GPC) where the polymer was dissolved in chloroform, the solvent for GPC was tetrahydrofuran, and the temperature was 23 °C. An important aspect of the present invention is that the random copolyesters do not contain any repeating units derived from succinic acid. In general, such compositions have been found to have poor physical properties, such as low tear strength and low transparency, both of which are important properties for corrosion-inhibiting compositions. Furthermore, aliphatic copolyesters such as PBS (poly(butylene succinate)) generally have poor mechanical properties and are expensive. Therefore, if used, the amount of any repeating unit derived from succinic acid is very small, such as less than approximately 10%, and desirably less than 2% based on the total number of repeating units in the copolymer.Preferably zero, i.e., no copolyester derived from succinic acid is used at all based on the total weight of the one or more biodegradable polyesters of the present invention. When a blend of one or more random copolymer polyesters is used with one or more homopolymer polyesters, the amount of the copolymer(s) is approximately 50% to approximately 95% by weight, desirably approximately 60% to approximately 90% by weight, and preferably approximately 70% to approximately 85% by weight, based on 100 total parts by weight of all biodegradable polyesters. The amount of one or more homopolymer polyesters is approximately 5% to approximately 50% by weight. desirably from approximately 10% to approximately 40% by weight, and preferably from approximately 15% to approximately 30% by weight based on 100 total parts by weight of all biodegradable polyesters. If the polyester inhibitor composition is not a blend, the amount of the homopolymer or random copolymer is, of course, 100% by weight. For example, it has been found that high proportions of one or more random copolyesters relative to the amount of one or more homopolyesters such as PLA are important for increasing the mechanical performance of the product and its lifespan. According to the present invention, biodegradable VCI packaging compositions may be made from one or more homopolymers as described above, or from one or more copolymers as described above, or from a mixture containing one or more homopolymers with one or more copolymers. Furthermore, in general, one or more fillers are always used with any of the three mixtures described above, as they have been found to unexpectedly improve the properties of the mixtures, as explained below. nQRCi η / ι ζπζ / ε / υιλι One or more volatile corrosion inhibitors of the present invention that may be used comprise various triazoles and derivatives thereof such as benzotriazole and tolytriazole; various benzoates such as ammonium benzoate; various ammonium salts; various carbamates; various phosphates; and various acid-alkali salts such as those set forth in U.S. Patents 4,973,448; 5,139,700; 5,715,945; 6,028,160; 6,156,929; 6,617,415; and 6,787,065, which are fully incorporated herein by reference.The useful VCIs of the present invention preferably include various inorganic nitrites or alkali metal nitrites, with potassium nitrite and sodium nitrite being preferred, as well as various sodium salts such as sodium octanoate, sodium benzoate, various benzoic acid derivatives such as 2-, 3-, or 4-hydroxybenzoic acid, ammonium benzoate, and various alkali metal (e.g., sodium or potassium) salts of aliphatic carboxylic acids such as sorbic acid or a dicarboxylic acid. Such acids have from approximately 5 to approximately 18 carbon atoms. Fillers are an important aspect of the present invention, providing ease of processing, such as resin extrusion and an anti-blocking effect for bags made with this material, cost reduction, retention of tensile strength, reduced density of the final product, and increased stiffness. It has also been found that various fillers, such as talc, calcium carbonate, sodium carbonate, silicates, clay, and barites, or any combination thereof, help adjust water vapor transmission rates (WVTR). Specifically, mixing these fillers into fully biodegradable VCI packaging compositions improves porosity and thus promotes the desired access of more water molecules to various VCI compounds.It has also been found that the higher water vapor transmission rate (WVTR) of biodegradable polyester films compared to polyethylene (PE)-based films allows for lower VCI compound loadings for short-term applications of the biodegradable VCI packaging compositions of the present invention. Talc is a preferred filler. The total amount of the one or more fillers is generally from approximately 3 to approximately 53 parts by weight, desirably from approximately 5 to approximately 33 parts by weight, and preferably from approximately 5 to approximately 18 parts by weight based on 100 total parts by weight of the one or more homopolymeric polyesters and / or one or more random copolymeric polyesters.Depending on the aspect ratio of the added fillers, breathability can be reduced or increased, thus helping to tailor the desired lifespan and service life for different applications based on the type of filler used. The present invention is starch-free as a filler; that is, it does not contain starch. A unique advantage of the present invention, due to the various factors contributing to its high weight-for-use ratio (WVTR), is that only small amounts of the VCI compounds are required. Specifically, the various VCI compounds range from approximately 0.1% by weight to approximately 10% by weight, desirably from approximately 0.3% by weight to approximately 5% by weight, and preferably from approximately 0.5% by weight to approximately 2% or approximately 0.9% by weight, based on the total weight (e.g., 100 parts by weight) of the one or more homopolymeric polyesters and / or the one or more random copolymeric polyesters. In other words, the total amount of the one or more VCI compounds used in the present invention can vary widely. The preparation of the different formulations of the biodegradable VCI packaging composition of the present invention can generally be carried out in any manner known in the art and literature. With respect to the present invention, several premixtures are initially prepared and subsequently blended together at a temperature above the melting point of the biodegradable compounds, such as the various types of polyesters disclosed earlier herein. For example, from approximately 1 to approximately 10 parts by weight of one or more VCIs are added to approximately 20 parts by weight of one or more random polyesters and / or one or more of the homopolymeric polyester polymers of the present invention to form a VCI premixture.Since the final total amount of VCI in the final composition is less than 10% by weight, based on the total weight of the one or more homopolymeric polyesters and / or the one or more copolymeric polyesters, the amount of VCI stock blend is subsequently added to a reasonable amount of biodegradable polyesters to produce a biodegradable polyester composition that has, as stated above, approximately 0.1% by weight to approximately 10% by weight, desirably approximately 0.3% by weight to approximately 5% by weight, and preferably approximately 0.5% by weight to approximately 2% by weight of a VCI therein based on the total weight of such polyesters alone.The preparation of the VCI master mix can generally be carried out in any heating and mixing device, such as an extruder, an internal mixer, or preferably a twin-screw extruder, where the mixing temperatures are above the melting point of the random copolyesters. A filler stock mix is ​​generally prepared in the same way, where small weights of the filler are added to a large quantity of one or more random copolyesters and / or one or more homopolymeric polyester polymers. Subsequently, a small amount of the filler stock mix is ​​added to a larger quantity of biodegradable polyesters to form a final composition containing the desired amount of filler. Naturally, the mixing temperature of the one or more fillers to form the filler stock mix is ​​above the melting point of the one or more random copolyesters. In other words, to prepare the formulations of the present invention, a composition is made containing 100 parts by weight of one or more homopolymeric polyesters and / or one or more random copolymeric polyesters. An appropriate amount of VCI is added to this, such that, based on a final total of 100 parts by weight of the desired biodegradable polyesters, the amount of VCI is, as indicated above, from approximately 0.1% to approximately 10% by weight. Subsequently, the filler stock is added in appropriate amounts so that the final total of one or more biodegradable polyesters is 100 parts by weight and the amount of the one or more fillers is within the weight ranges indicated above.That is, once the various desired stock blends have been prepared with respect to the one or more VCI compounds and the one or more filler compounds, all the necessary stock blends are mixed together with additional quantities of biodegradable random copolyesters and / or a desired quantity of one or more biodegradable homopolyesters to form the final biodegradable VCI packaging composition. The blending can be carried out in any desired blending device such as a calender, extruder, etc., and the product is shaped either into pellets, granules, and the like, or directly formed into the final product, such as a sheet, bag, or wrap of the desired thickness. With respect to the present invention, the sheets have a thickness of approximately 0.5 to approximately 8 mils, and desirably from approximately 0.8 to approximately 5.0 mils, and preferably from approximately 1.5 to approximately 2 mils.A thickness of 5 thousandths can subsequently be used to form a container, enclosure, or the like to protect a metal article or component from corrosion. Furthermore, the packaging composition of the present invention can be one or more laminates having one or more sheets therein. For example, a first sheet can comprise one or more homopolymeric polyester polymers and the aforementioned one or more random copolymeric polyesters containing a volatile corrosion inhibitor (VCI) therein, and one of the aforementioned fillers therein. A second sheet of the laminate can comprise only such one or more biodegradable random copolymeric polyesters, optionally comprising a filler and optionally comprising a VCI. It should be obvious that many other different types of laminates can be made from the biodegradable volatile corrosion inhibitor polyester compositions of the present invention. In accordance with the present invention, breathable biodegradable volatile corrosion inhibitor packing compositions can be prepared having a wide WVTR range such as from about 100 to about 2000, desirably from about 300 to about 1000, and preferably from about 400 to about 600[g / (m2 d) ] at 38 °C / 90% RH, normalized to 1 thousandth in accordance with ASTM F1249. The present invention will be better understood by reference to the following examples, which serve to illustrate, but not to limit, the present invention. The following standard tests were performed to determine the properties of the prior art as well as the present invention. EXAMPLE 1: PBAT pellets were dried at 50°C for a minimum of 2 hours and blended with ground sodium nitrite powder (VCI#1) in a 70:30 ratio. The mixture was then fed into the feed hole of a LabTech® counter-rotating twin-screw extruder with an L / D of 44 and a screw diameter of 26 mm, in which most zones were controlled at temperatures in the range of approximately 132.22°C (270°F) to 143.33°C (290°F). The die temperature was maintained at 148.89°C (300°F). The motor speed was approximately 150 rpm and produced a strand that was cooled in a water bath, pelletized into pellets of approximately 3.18 mm (0.125 in), and dried. The VCI MB was then mixed with similarly dried PBAT and PBAT / filler pellets and / or PLA as indicated in Table 1 and extruded into a film through a blown film line, run at 0.0254 m / s (5 ft / min) to 60 microns thick. nQACi η / ι ζπζ / β / υιλι A control sample was made with a mixture of LDPE and LLDPE with a comparable level of VCI in it for comparison. In contact corrosion tests, the panel inside the PE-based resin, which has a lower WVTR, showed several areas of corrosion along the edges and more than three points on the panel body when tested in accordance with IEC 68-2-30 Cyclic Chamber Tests. The panels in PE bags, which would be the control, received grade 3, while the panels in this example with biodegradable resins, PBAT / filler and PBAT / PLA / refiller mixture, showed no corrosion and were rated 5, after 7 cycles. The WVTR of the LDPE / LLDPE (Control) sample was less than 11 [g / (m2.d) ] versus more than 300 [g / (m2.d) ] at 38 °C / 90% RH for the above Example 1. VCI tests in accordance with NACE Standard TM0208 showed a grade 3 for the biodegradable sample of the present invention and a grade 2 for the PE-based control sample with a comparable VCI content. Example PBAT PLA VCI Filler 1 1 100 0 8.18777 0.98253 1 100 5.77367 8.18777 0.98253 The same drying procedure and the same equipment and composition procedure were used for all the examples included here. Example 2. Another sample was made using a similar process of preparing a first base mix (BM) and then blending it with the film resins. A different powder mix chemistry was used, and its effectiveness was evaluated. The powder mix consisted of 68% sodium octanoate, 7% 4-hydroxybenzoate, 3% benzotriazole, and 22% ammonium benzoate. This mix will be referred to as VCI#2. The mix was then blended with PBAT pellets in a 70:30 ratio to create a master mix. This was compared to 87% sodium octanoate, 9% 4-hydroxybenzoate, and 4% benzotriazole, called VCI#3. Each powder mixture was then blended with PBAT pellets in a 70:30 ratio to create the master mix. The film was then made by blending the master mix in subsequent batches with PLA, PBAT, and filler, with the remaining PBAT comprising the master mix. Cyclic atmospheric chamber contact tests performed in accordance with (IEC 68-2-30) for both examples showed that the first mixture VCI#2 noftci η / ι ζπζ / ε / υιλι obtained a protection rating of 4-5 compared to VCI#3 which obtained a rating of 2. The NACE Standard TM0208 test showed a grade 3 for the first formulation and a grade 1 for the second group. Example PBAT PLA Filling VCI 2 VCI 3 2 83.89 16.11 6.44468 1.15237 0 2 83.89 16.11 6.44468 0 1.15237 Example 3. Similar to Example 1, but with a different VCI chemistry, VCI#2 was added to a similar PBAT / filler charge in one case, and to the LDPE / LLDPE mixture in another case as the control. The PBAT / VCI film showed no corrosion (grade 5), while several spots (grade 3) were observed in the control, the LDPE / LLDPE film with a comparable VCI concentration, after 1 week of testing, 7 cycles of (IEC 68-2-30). Example PBAT PLA VCI Filler 2 3 100 0 8.188 0.98253 Example 4. VCI#2 was added to the PBAT / fill mixture with the same load, the difference between the two sets being the fill level, one with a lower fill level and the other with a higher fill level. The film with the highest fill level showed better protection in the cyclic chamber test, which was run in accordance with IEC 68-2-30 after two weeks (14 cycles). The rating for the highest fill level was 4-5, while it was 3-4 for the lowest fill level samples. The water vapor transmission rate (WVTR) of the film with the highest fill level was 412 g / (m² d) compared to 323 g / (m² d) (normalized) for the lower fill level, tested at 38 °C / 90% RH. noRci n / ι ζπζ / β / υιλι Example PBAT PLA VCI Filler 2 4 100 0 17.417 1.06635 4 100 0 8.18777 0.98253 Example 5. The VCI#3, which showed a weaker result in example #2, showed an improved result when used with a higher fill level. While the sample with the lower fill level showed a grade 2 after 14 test cycles (IEC 68-2-30), the sample with the higher fill level showed a grade 3. Example PBAT PLA VCI Filler 3 5 100 0 17.417 1.06635 5 100 0 8.18777 0.98253 Although, in accordance with the patent statutes, the best mode and preferred modality have been set forth, the scope of the invention is not limited to this, but to the scope of the attached claims.

Claims

1. A biodegradable volatile corrosion inhibitor polyester composition, comprising: polyester comprising one or more biodegradable random copolymeric polyesters and / or one or more biodegradable homopolymeric polyesters; volatile corrosion inhibitors comprising: (i) one or more carboxylic acid salts, (ii) one or more ammonium salts, and (iii) one or more benzoic acid, sorbic acid and a benzoic acid derivative; and at least one filler.

2. The composition of claim 1, comprising one or more copolymeric polyesters having the formula: wherein R1 is x is an integer in the y is an integer in the range of 2 to 10, range of 2 to 8; ymyn are selected such that the weight average molecular weight of the copolymeric polyester is from approximately 80,000 to approximately 175,000.

3. The composition of claim 1, comprising one or more copolymeric polyesters selected from polybutylene sebacate-co-terephthalate (PBST) and polybutylene adipate-co-terephthalate (PBAT).

4. The composition of claim 1, comprising one or more copolymeric polyesters not containing any succinic acid-derived repeating unit.

5. The composition of claim 1, comprising one or more homopolymeric polyesters selected from polylactides, polycaprolactones, polyglycolides, polyhydroxyalkanoates and combinations thereof.

6. The composition of claim 5, wherein the homopolymeric polyester comprises a polylactide and the filler comprises talc. nQRCi η / ι ζπζ / ε / υιλι 7. The composition of claim 1, comprising a mixture of one or more copolymeric polyesters and one or more biodegradable homopolymeric polyesters, wherein the total weight of the copolymeric polyesters is approximately 50% to approximately 95% by weight based on the total weight of the mixture, and the total amount of the homopolymeric polyesters is approximately 5% to approximately 50% by weight based on the total weight of the mixture.

8. The composition of claim 1, wherein the weight average molecular weight of the one or more copolymeric polyesters is from approximately 90,000 to approximately 150,000, and the weight average molecular weight of the one or more homopolymeric polyesters is from approximately 125,000 to approximately 140,000.

9. The composition of claim 1, wherein the volatile corrosion inhibitors are present in a total amount of approximately 0.1% by weight to approximately 10% by weight based on the total weight of the polyester.

10. The composition of claim 1, wherein the volatile corrosion inhibitors comprise one or more of sodium octanoate, ammonium benzoate and sorbic acid.

11. The composition of claim 1, wherein the one or more carboxylic acid salts comprise one or more alkali metal salts of aliphatic carboxylic acids having from 5 to 18 carbon atoms.

12. The composition of claim 1, wherein the volatile corrosion inhibitors consist of: (i) one or more carboxylic acid salts, (ii) one or more ammonium salts, and (iii) one or more benzoic acid, sorbic acid, and a benzoic acid derivative.

13. The composition of claim 1, wherein the at least one filler comprises talc, calcium carbonate, a silicate, sodium carbonate, clay, barite or a combination thereof.

14. The composition of claim 1, comprising from approximately 3 to approximately 53 parts by weight of filling based on 100 total parts by weight of polyester.

15. The composition of claim 1, wherein the composition exhibits a protective effect against corrosion of Grade 3 or higher in accordance with NACE Standard TM0208.

16. A film comprising the composition of claim 1, wherein the film has a thickness of approximately 0.5 mils to approximately 8 mils.

17. A concentrate containing volatile corrosion inhibitors, comprising: volatile corrosion inhibitors comprising: (i) one or more carboxylic acid salts, (ii) one or more ammonium salts, and (iii) one or more benzoic acid, sorbic acid, and a benzoic acid derivative; and polyester comprising one or more biodegradable random copolymeric polyesters and / or one or more biodegradable homopolymeric polyesters; wherein the ratio of volatile corrosion inhibitors to polyester in the concentrate is in the range of approximately 1:20 to approximately 10:20.