FR3040389A1 - FOOD-CONTACTABLE BIODEGRADABLE PLASTIC COMPOSITION, DERIVANT ARTICLES, METHODS AND USES THEREOF - Google Patents

Abstract

A biodegradable plastic composition suitable for food contact, an article for the storage or packaging of seafood and obtained from this biodegradable plastic composition, and methods and uses thereof have been developed. The compositions and articles are biodegradable and / or compostable.

Description

Biodegradable plastic composition suitable for food contact, articles thereof, methods and uses thereof 1. Field of the invention

The field of the invention is that of articles intended for the storage, packaging, transport and / or distribution of seafood products, in particular fish, cephalopods, crustaceans, shellfish and algae.

More specifically, the invention relates to a biodegradable plastic composition suitable for food contact, method of manufacture and corresponding use. The invention also relates to articles for the storage or packaging of seafood products, obtained in particular from said biodegradable plastic composition, and corresponding manufacturing method and use. 2. Prior Art

The consumption of seafood is dependent on many constraints related to their harvest or fishing, storage, distribution, transport and delivery. Indeed, the distance is often great between the place of harvest or fishing and the place of sale to the intermediary or to the final consumer. In addition, seafarers, wholesalers and retailers have a duty to maintain the cold chain strictly in order to ensure the provision of fresh and consumable seafood to the end consumer.

In order to assist them in their task, sea professionals, wholesalers and retailers use crates of fish auction, also called fish boxes. These fish crates, which are generally standard in shape and size, make it easy to store seafood products, while optimizing their storage, facilitating their transport from one place to another and their exchange from one person to another. . These fish boxes are stackable and can optionally be stacked to be suitable for transporting, storing and storing goods.

The fish crates are generally crates made from petroleum-based plastics, that is to say obtained from compounds derived from petroleum. Compounds derived from petroleum are, for example, polyethylenes (PE) or polypropylenes (PP) to which additives modifying their properties are added. These articles have a very good impact resistance, they are suitable for use in the marine environment and they have a long life.

However, these articles have the disadvantage of being obtained from non-biodegradable materials, and are therefore potentially polluting. When these items are abandoned in the natural environment, for example in the marine environment or on the coasts, they will pollute the site for a long time, sometimes for hundreds of years. In addition, as they become degraded and decomposed, these articles may release pollutant chemicals into the environment. Finally, the fragmentation of articles into fragments and plastic particles will contribute to a lasting pollution of the oceans, and to a weakening of the aquatic and oceanic fauna by ingestion of these fragments and particles.

To limit pollution, recycling channels have been set up to ensure the collection, treatment and potentially reuse of used items. Such channels are generally expensive to implement and only allow partial recycling of used items. In fact, only two types of plastics are recycled, namely PET (used in particular for the manufacture of transparent or colored bottles) and PeHD (used in particular for the manufacture of opaque bottles). Other plastics such as PVC or supermarket bags are not recycled because of the prohibitive cost. Instead, they are burned in incinerators to produce energy (referred to as "energy upgrading"). However, plastic is not infinitely recyclable, like glass: recycling it only delays the moment when it will burn.

In order to limit the life of articles that are suitable for food contact, particularly in order to accelerate their degradation or decomposition, while minimizing the amount of chemical polluting compounds, alternative plastic compounds have been used, possibly in combination with additional compounds. . For example, there are known articles comprising plastic compounds selected from polyglycolic acid, polylactic acid, polyhydroxyalkanoate, polybutylene succinate-co-adipate, polybutylene succinate-co-lactate, polybutylene adipate-co- terephthalate, poly-epsilon caprolate, polydioxanone.

Although some of these items are effectively adapted to different types of food products, such as fruits and vegetables, they are not necessarily suitable for the storage and packaging of seafood. In fact, seafood is sins. or harvested in an "aggressive" environment, due to the high salinity of the seawater and the high exposure to ultraviolet rays. In addition, the respect of the cold chain, which corresponds to all logistical and domestic operations (transport, handling, storage) aimed at keeping food products at a given temperature in order to preserve its safety and taste qualities. , causes frequent temperature changes. Thus, depending on the products, the standards set the limit temperatures and overtaking tolerances of 0 ° C to + 2 ° C for fresh fish. Finally, the distance between the place of harvest or fishing and the place of sale, and the multiple stakeholders, require a good resistance to shocks.

To limit the environmental impact, it is therefore necessary to provide plastic compositions, and plastic articles obtained from them, which are biodegradable and / or compostable. It is therefore useful to provide plastic compositions, and plastic articles made therefrom, that do not include petroleum-based plastic compounds. Conversely, it is useful to provide plastic compositions, and plastic articles made therefrom, which include biosourced plastics compounds. In addition, it is necessary to provide plastic compositions, and plastic articles obtained therefrom, which exhibit sufficient resistance to aggressive environmental conditions, including high salinity or high exposure to ultraviolet radiation. Finally, it is therefore necessary to provide plastic compositions, and plastic articles obtained from them, which have a high impact resistance. 3. OBJECTIVES OF THE INVENTION The object of the invention is notably to overcome these disadvantages of the prior art.

More specifically, an object of the invention is to provide, in at least one embodiment, a plastic composition, and a plastic article obtained therefrom, which is biodegradable and / or compostable.

Another object of the invention is to provide, in at least one embodiment, a plastic composition, and a plastic article obtained therefrom, obtained at least partially from biosourced compounds.

Another object of the invention is to provide, in at least one embodiment, a plastic composition, and a plastic article obtained therefrom, having a high resistance to aqueous media.

Another object of the invention is to provide, in at least one embodiment, a plastic composition, and a plastic article obtained therefrom, having a high resistance to salinity and exposure to ultraviolet rays. .

Another object of the invention is to provide, in at least one embodiment, a plastic composition, and a plastic article obtained therefrom, having a high impact resistance.

Another object of the invention is to provide, in at least one embodiment, a method of manufacturing said plastic composition, and said plastic article obtained therefrom.

Finally, another object of the invention is to provide, in at least one embodiment, a plastic article that can be used for storing and packaging products intended for human or animal consumption, in particular seafood products. 4. Presentation of the invention

These objectives, as well as others that will appear later, are achieved with a biodegradable plastic composition suitable for food contact, and using a biodegradable plastic article suitable for food contact and for storage and / or the packaging of seafood.

According to the invention, such a composition comprises, in total weight of the composition: from 50% to 75% of a first bioplastic polymer, said first bioplastic polymer being poly (butylene succinate); from 1% to 25% of a second bioplastic polymer, said second bioplastic polymer being selected from the group consisting of polylactic acid, polyhydroxyalkanoate, and mixtures thereof; from 1% to 10% of a mineral filler; from 1% to 15% of a plasticizer compound; from 1% to 5% of a fatty acid; optionally a chain extender compound.

In a particular embodiment of the invention, the composition may comprise a second bioplastic polymer, said second bioplastic polymer being polylactic acid; alternatively said second bioplastic polymer being polylactic acid without GMO.

The composition may further comprise a mineral filler being calcium carbonate.

The composition may further comprise a plasticizer compound, said plasticizer compound being selected from the group consisting of polyvinyl acetate and its derivatives; alternatively from the group consisting of ethylene vinyl polyacetate, polyvinyl acetate, and mixtures thereof; alternatively the plasticizer compound is ethylene vinyl polyacetate.

The composition may further comprise a fatty acid, said fatty acid being selected from the group consisting of unsaturated fatty acids; alternatively from the group of polymerized unsaturated fatty acids; alternatively the group consisting of unsaturated fatty acid dimers, unsaturated fatty acid trimers, and mixtures thereof.

The composition may further comprise a chain extender compound, wherein said chain extender compound is selected from the group consisting of a multifunctional epoxy compound. Said composition may comprise from 0.1% to 0.5% of said chain-extending compound, by total weight of the composition.

Said composition may further comprise natural pigments. Said composition may comprise from 0.01% to 10% of natural pigments, by total weight of the composition. Said natural pigments can be obtained from organic pigments and / or dyeing plants.

In a second aspect, the invention relates to a method of manufacturing said biodegradable plastic composition, said process being selected from the group consisting of extrusion, injection, thermoforming, calendering, additive manufacturing processes, and their processes. combinations; alternatively the process being an injection process.

In a third aspect, the invention relates to a food contactable article comprising walls having an average thickness of at least 2 mm, said article being obtained from said biodegradable plastic composition.

Said food-contactable article may comprise walls with an average thickness of at least 2 mm, said article comprising, in total weight of said article: from 50% to 75% of a first bioplastic polymer, said first bioplastic polymer being poly (butylene succinate);

from 1% to 25% of a second bioplastic polymer, said second bioplastic polymer being selected from the group consisting of polylactic acid, polyhydroxyalkanoate, and their bioplastic mixture being polylactic acid without GMO from 1% to 10% d a mineral charge; from 1% to 15% of a plasticizer compound; from 1% to 5% of a fatty acid; optionally a chain extender compound

Said article can be a tide box; alternatively said article may be a fish crate.

In a fifth aspect, the invention relates to a method of manufacturing a food-contactable article, comprising: providing said biodegradable plastic composition; injecting said composition into an article comprising walls having an average thickness of at least 2 mm

In a sixth aspect, the invention relates to the use of said article suitable for food contact, for the storage or packaging of a product for human or animal food; alternatively for the storage or packaging of a product of the sea; alternatively for storing or packaging a seafood product selected from the group consisting of fish, cephalopods, crustaceans, algae, and mixtures thereof; alternatively for storing or packing fish.

In a final aspect, the invention relates to the use of said biodegradable plastic composition for the manufacture of articles suitable for food contact.

"Bio-based" or "biosourcing" refers to plastics made from plant-based resources such as maize, cassava, potatoes, wood, cotton, seaweed, etc.

"Biodegradable" or "biodegradable" means the decomposition of an organic chemical compound into carbon dioxide, water and mineral salts, other elements present (mineralization) and the appearance of a new biomass, under the action of micro -organisms in the presence of oxygen; or the decomposition into carbon dioxide, methane, mineral salts and the creation of a new biomass, in the absence of oxygen (see EN 13432: 2000).

The term "compostable" or "compostability" refers to a process that consists of placing fermentable products under conditions (temperature, humidity, oxygenation, presence of soil micro-organisms, etc.) that allow them to biodegrade. To be considered compostable according to EN 13432, the material must be degraded to 90% of its mass after 6 months in an industrial compost medium; the size of the residues must be less than 2 mm after 3 months of composting; and the absence of ecotoxic effects must be demonstrated as well as the agricultural quality of the compost obtained.

The European standard EN 13432, entitled "Requirements for packaging recoverable by composting and biodegradation - Test program and evaluation criteria for the final acceptance of packaging", and adopted in France under the name NF EN 13432, defines the characteristics of "compostable" or compatible packaging in an organic recycling sector (by composting or anaerobic digestion). It applies to both plastic packaging and ligno-cellulosic materials, although it excludes from its scope non-packaging plastics (such as plastics used in agriculture, bags for waste collection).

Standard NF EN 14995 (Plastics - Evaluation of compostability - Test program and specifications) fills this gap. From the technical point of view, it is identical to standard NF EN 13432, but it covers a larger number of applications, other than packaging. The similarity of the technical content of the two standards means that a plastic material conforming to the NF EN 13432 standard is also compliant with NF EN 14995 and vice versa.

These two standards constitute the most important technical reference for material producers, public authorities, composting platforms, certification bodies and consumers.

The term "seafood" refers to fauna and flora collected from aquatic, coastal and lacustrine waters and intended for human or animal consumption, including fish, cephalopods, crustaceans, shellfish and algae.

Thus, the invention is based on a completely new and original approach to provide a composition of several carefully selected compounds, and adjusted proportions. The incorporation of poly (butylene succinate) as a bioplastic polymer, supplemented by the incorporation of a second bioplastic polymer being polylactic acid and / or polyhydroxyalkanoate, has proved particularly interesting. Indeed, the inventors have demonstrated that the formulation of poly (butylene succinate) with a mineral filler, a plasticizer compound, a fatty acid, a second specific bioplastic polymer and optionally an extender chain compound, allowed the production of a composition biodegradable plastic, and an article obtained therefrom, with improved properties. Indeed, this combination of specific compounds in adjusted proportions has made it possible to compensate for the weak mechanical properties of poly (butylene succinate), while obtaining a composition having a satisfactory hydrophobic character, in which the various compounds are dispersed in a homogeneous manner, in order to to control the hydrolysis of poly (butylene succinate) and thus to increase the life of the articles. The inventors have demonstrated in particular that these compositions and articles were suitable for food contact, had a high resistance to shocks, aqueous media, salinity and ultraviolet rays, while being biodegradable and / or compostable. This article has therefore proved particularly suitable for the storage, packaging, transport and / or distribution of seafood products.

In particular, the work carried out by the inventors has made it possible to observe that the mineral filler makes it possible to improve the mechanical properties of the composition and to increase its resistance to water, provided that it is incorporated in a proportion allowing its good dispersion (and according to a defined implementation method).

In addition, the fatty acid, because of its hydrophobic character, also enhances the water resistance and limits the hydrolysis of poly (butylene succinate). The addition of this fatty acid, however, reduces the molecular weight of said composition, so it must be incorporated into the biodegradable plastic composition at an adjusted concentration. Indeed, if the molar mass of said composition is too low, it will reach its critical molar mass (Mc), mass or which said composition passes from the ductile transition (flexible) to brittle (brittle), making said composition non-compliant with the desired application, the biopolymer becoming without sufficient thermal and mechanical resistance. This critical molar mass is also an indicator in terms of recovery (recycling, biodegradability, compostability).

In parallel, the chain lengthening compound makes it possible to increase the molar mass considerably, allowing the said composition to be more durable and thus to meet the technical requirements for the duration of use of the fish boxes. The addition of this chain extender also makes it possible to reduce the morphology of the mixtures by reducing the size of the nodules, it thus plays the role of compatibilizer between the biopolymers because it significantly decreases the size of the phases and leads to a greater morphology. fine. The addition of this chain extender is optional. Indeed, the need to add a chain extender compound will be a function of the molar mass of the first bioplastic plastic, that is to say poly (butylene succinate). If the PBS has a molar mass of at least 150000g / mol, preferably between 150000g / mol and 300000g / mol, very preferably about 200000g / mol, the addition of a chain extender compound will not be necessary. Conversely, if the PBS has a molar mass of less than 150000g / mol, preferably between 34700g / mol and 150000g / mol, the addition of a chain compound will be useful in order to increase the molar mass of the PBS to a threshold value. minimum of 150000g / mol.

A chain extender has two functional groups capable of reacting with the carboxylic acid or alcohol functions of PBS. The amount of this agent must be optimized to couple two chains of PBS. Many chain extenders are used in polyesters to increase their molecular weight, such as diepoxys and bisoxazolines which preferentially react with carboxylic acid functions, and diisocyanates, biscaprolactams and dianhydrides which react with alcohol functions.

In order to potentiate the properties of the above compounds and to enhance their compatibility, a plasticizing compound is added. This makes it possible to improve the properties of elasticity, impact resistance and rheology of polybutylene succinate.

Finally, the second bioplastic polymer is particularly useful in that it mechanically strengthens the mixture. The method of implementation is also important. Indeed, the formulation implemented in one step limits little hydrolytic degradation of PBS, only a slight improvement is observed by the incorporation of the mineral filler. In contrast, when the formulation is carried out in two stages, a significant improvement in stability against hydrolysis has been observed. These observations confirm the fact that the mineral filler preferentially interacts with the second bioplastic polymer when the extrusion is carried out in one step and does not make it possible to limit the degradation of the PBS, whereas it is distributed uniformly in the material when the extrusion is carried out in two stages. The dispersion of the mineral filler increases. The mechanical properties of the composition obtained are thus improved by avoiding the agglomerates of inorganic filler particles which reduce the elongation at break of said composition.

Advantageously, the composition comprises from 50% to 75% of a first bioplastic polymer, said first bioplastic polymer being poly (butylene succinate). Preferably, the poly (butylene succinate) is biobased.

Poly (butylene succinate) may have a molar mass of at least 150000 g / mol, preferably between 150000 g / mol and 300000 g / mol, very preferably about 200000 g / mol. When the poly (butylene succinate) has a molar mass of at least 150000 g / mol, it is generally not necessary to add a chain extender compound to said composition.

Alternatively, the poly (butylene succinate) may have a molar mass of less than 150000 g / mol, preferably between 34700 g / mol and 150000 g / mol. When the poly (butylene succinate) has a molecular weight of less than 150000 g / mol, it is useful to add a chain-lengthening compound to said composition, in order ultimately to obtain a poly (butylene succinate) of sufficient molar mass.

Different modes of synthesis of PBS are known. A first method, the most widespread and the simplest, is the direct polymerization in the molten route. PBS of high molar mass is obtained from succinic acid and 1,4-butanediol, in the presence of a catalyst based for example on antimony, tin and titanium, such as tetrabutyl titanate. and isopropyl. A second method is direct solvent polycondensation, the distillation of water under azeotropic conditions allowing the preservation of a high concentration of reagents and the formation of relatively high molecular weight polymers. A third method is transesterification polymerization, with PBS synthesized in bulk from dimethyl succinate and 1,4-butanediol, and having a low molecular weight. A fourth method is the synthesis of PBS by polycondensation can be followed by an extension of chains, allowing the production of PBS of high molar mass. A PBS obtained by this method is marketed by Showa Denko under the name PBS 1020 (molar mass of 200,000 g / mol).

The composition further comprises from 1% to 25% of a second bioplastic polymer. Preferably, the second bioplastic polymer is biobased. Said second bioplastic polymer is selected from the group comprising polylactic acid, polyhydroxyalkanoate, and mixtures thereof; alternatively the second bioplastic polymer is polylactic acid; alternatively the second bioplastic polymer is polylactic acid without GMO. A non-GMO polylactic acid is a polylactic acid obtained from non-genetically modified organisms. These polymers are available under the trade names NaturePlast (PLE 005) for non-GMO PLA and an experimental PHA from research work in a scientific laboratory.

The composition may comprise a mineral filler being calcium carbonate. Sources of calcium carbonate are available under the trade name OSTREASHELL company Entre Mer et Terre.

The composition may comprise a plasticizer compound selected from the group consisting of polyvinyl acetate and its derivatives; alternatively from the group consisting of ethylene vinyl polyacetate, polyvinyl acetate, and mixtures thereof; alternatively the plasticizer compound is ethylene vinyl polyacetate. Plasticizers are available under the trade name Vinnex® from Wacker AG or Polysorb® (chemical name: Isosorbide) from Roquette.

The composition may comprise a fatty acid selected from the group consisting of unsaturated fatty acids; alternatively from the group of polymerized unsaturated fatty acids; alternatively the group consisting of unsaturated fatty acid dimers, unsaturated fatty acid trimers, and mixtures thereof. Fatty acids are available under the trade name Pripol ™ from Croda. These are side alkyl chain comonomers having a more hydrophobic character than the monomers of PBS. These fatty acids have groups of carboxylic acids as terminal reagents. The fatty acids marketed under the name Pripol ™ are derived from the transformation of natural fatty acids. The longer the side alkyl chain, the greater the surface hydrophobicity. The angle of contact with water, and hence the hydrophobicity of the copolymers, increases with the incorporation of side alkyl chains into the PBS chain. Also, Croda's Pripol 1009F was chosen for its long 36-carbon alkyl chain, increasing the hydrophobicity of PBS and limiting its hydrolytic degradation - its chemical formula is as follows:

The composition may comprise a chain extender compound selected from the group consisting of a multifunctional epoxy compound. Chain extender compounds are available under the trade name Joncryl® from BASF having about 9 epoxy functions per mole and having a high reactivity with acid functions. The chain extending compounds may comprise the chemical formula moiety:

Wherein the radicals R 1 to R 5 are independently selected from H, CH 3, or an alkyl group; wherein the radical R6 is an alkyl group; and wherein the indices x, y, z are included, independently of one another, between 1 and 20.

The composition may be devoid of additional bioplastic polymer other than said first and second bioplastic polymers. In particular, the composition is devoid of a bioplastic polymer selected from the group consisting of polyglycolic acid, polybutylene succinate-co-adipate, polybutylene succinate-co-lactate, polybutylene adipate-co-terephthalate, poly-epsilon caprolate polydioxanone, and mixtures thereof.

According to the invention, said biodegradable plastic composition may be manufactured by a manufacturing method selected from the group consisting of extrusion, injection, thermoforming, calendering processes, additive manufacturing processes, and combinations thereof; alternatively by an injection method. By way of example, additive manufacturing processes include melt deposition (FDM) printing and stereolithography (SLS).

Preferably, said biodegradable plastic composition is manufactured by a manufacturing method comprising the following steps: a) providing a first bioplastic polymer being poly (butylene succinate), a second bioplastic polymer selected from the group consisting of polylactic acid, polyhydroxyalkanoate, and mixtures thereof, a mineral filler, a plasticizer compound, a fatty acid and optionally a chain extender compound; b) extrusion blending said first bioplastic polymer, said second bioplastic polymer, at least a portion of said plasticizer compound, said fatty acid and optionally said chain extender compound to obtain a first blend; c) addition by extrusion to said mixture of the remainder of said plasticizer and said mineral filler, to obtain a biodegradable plastic composition.

The implementation of a two-step process has the advantage of making it possible to obtain a biodegradable plastic composition having good stability to hydrolysis, particularly because of the good dispersion of the mineral filler.

According to the invention, said composition is used for the manufacture of articles suitable for food contact. Indeed, the invention also relates to the ecodesign articles intended for the storage or packaging of seafood, obtained from said biodegradable plastic composition in order to limit the environmental impacts during the life cycle of the product (raw materials, process, manufacturing, consumption, transportation, end of life, etc.).

According to the invention, the article comprises walls having an average thickness of at least 2 mm and is obtained from said biodegradable plastic composition. The article comprises walls of an average thickness of at least 2mm; alternately from 2mm to 4mm; alternatively about 3mm. The article comprises, in total weight of said article: from 50% to 75% of a first bioplastic polymer, said first bioplastic polymer being poly (butylene succinate); from 1% to 25% of a second bioplastic polymer, said second bioplastic polymer being selected from the group consisting of polylactic acid, polyhydroxyalkanoate, and mixtures thereof; from 1% to 10% of a mineral filler; from 1% to 15% of a plasticizer compound; from 1% to 5% of a fatty acid;

The composition may further comprise a chain extender compound. The article is preferably obtained by injection of said biodegradable plastic composition. Indeed, the inventors have found that said biodegradable plastic composition being particularly suitable for injection processes, thereby allowing easy manufacture of the article.

Preferably, the article has the shape of a box. Said body comprises a substantially horizontal wall forming the bottom of the body and at least one substantially vertical side wall. The essentially horizontal wall and the essentially vertical wall (s) define a volume in which seafood can be stored and packaged. The bottom (horizontal wall) of the article may have a square or rectangular section, in which case it is circumscribed by four side walls.

The sizing of the bins is based on the restriction of refrigerated vessel traps and spaces of road transport vehicles. Generally, fish tanks have classic dimensions even if some bins suppliers have special dimensions. In itself, there is no regulated and mandatory sizing. However a European transport standard has been created for these bins. Standard plastic stacking bins are suitable for European pallets (800 x 1200 mm or 1000 x 1200 mm). The EURO standard for these bins accepts the following dimensions: 800x400mm; 800x600mm; 600x400mm; 400x300mm; 300x200mm; 200x150mm (see also ISO 3394).

When the bottom is of square section, the article can have a width of 150mm to 800mm and a height of 100mm to 250mm. When the bottom is of rectangular section, the article can have a width of 150mm to 600mm, a length of 200mm to 800mm and a height of 100mm to 250mm.

In a particularly preferred manner, the article is a fish crate.

According to the invention, the method of manufacturing an article suitable for food contact comprises: providing said biodegradable composition; and injecting said composition into an article comprising walls having an average thickness of at least 2mm.

According to the invention, said article is used for storing or packaging a product intended for human or animal food; alternatively for the storage or packaging of a product of the sea; alternatively for storing or packaging a seafood product selected from the group consisting of fish, cephalopods, crustaceans, algae, and mixtures thereof; alternatively for storing or packing fish. 5. Description of embodiments of the invention

Formulation

Several compositions have been implemented. These compositions comprise the compounds and proportions as indicated in Table 1 below:

Table 1

The compounds are expressed as a percentage (and by weight) of active ingredients (compounds as such, and not as a percentage (and by weight) of the raw materials containing them.

The following sources of compounds are used: PBS 1020 Showa Denko for poly (butylene succinate), molar mass of about 200000g / mol, obtained by polycondensation, followed by chain extension with hexamethylene 1,6-diisocyanate - OSTREASHELL from Between Sea and Earth for Calcium Carbonate - Vinnex 2504 from Wacker AG for Ethylene Polyvinyl Ether

Croda Pripol 1009F for Fatty Acid - BASF Joncryl ARD 4368 for NaturePlast Non-GMO Chain Extender Compound - PLE 005 for Second Bioplastic Polymer

Mechanical, chemical and physical properties

The compositions according to the invention have mechanical, chemical and physical properties, which make them particularly suitable for the manufacture of articles intended for use for the storage and packaging of seafood products. facilitated manufacture of the corresponding compositions and articles, and ensure their recyclability, in particular their biodegradability and / or their compostability.

The compositions and articles have the following properties detailed in Table 2 below:

Table 2

The measurements made on the plastic compounds used and the compositions obtained are compiled in Table 3 below.

Table 3

Processes for manufacturing the composition according to the invention

The composition is compounded by extrusion. That is, the biopolymers and additives are mixed using an extruder. The extruder used for the tests is a laboratory single-screw mini-extruder. It comprises an endless screw which rotates inside the cylindrical sheath regulated in temperature by heating and cooling systems. The biopolymers and the additives are inserted, in a precise order, into the hopper at the end of the machine. The function of the extruder is to convey the biopolymers and additives of said composition, melt, pressurize and mix to obtain a rod at the die outlet. The rod is then cooled, either by compressed air, or in a cooling bath, or both, and then granulated to obtain said composition which will then be implemented by injection.

For each range of said composition, 1 kg of material was prepared. The temperatures of the different zones of the extruder were adjusted in accordance with the phase change temperatures of the biopolymers of said composition. Adjusting the screw speed inside the sheath made it possible to ensure the proper mixing of said composition by shearing material.

More descriptively, the compounding of said composition is established as follows: 1) Compounding / extrusion according to the composition of the PBS, PLA, half the percentage of plasticizer, the hydrophobic agent and optionally the chain extender. The compounds are then mixed in the screw to be extruded and then granulated. Another solution is to compound the composition of the PBS, PLA, half the percentage of plasticizer, optionally the chain extender and to incorporate the hydrophobic agent by extrusion liquid additive dosing. 2) Compounding composition 1 with the incorporation of the other half of the percentage of plasticizer and the mineral filler.

The fact of proceeding in 2 steps is important for the good stability to hydrolysis due to the good dispersion of the mineral filler.

If the mixture was made in a single step, said composition would promote the appearance of agglomerates of the mineral filler due to poor dispersion; which would lead to a decrease in mechanical properties, water resistance and an increase in the rate of degradation. In addition, the one-step mixture would not allow the chain extender to react with the biopolymers because the inorganic filler prevents this reaction. Single-screw extruder settings for different tests:

Table 4

Currently, the extruded material is mainly HDPE with processing temperatures between 200 and 280 ° C. Said composition having an operating temperature of between 180 and 195 ° C., the invention also relates to the reduction of environmental impacts during the implementation step with the reduction of the heating temperatures from 5 to 100 ° C. resulting in a reduction of the energy consumption of the machine and also a reduction of the machine heating time.

Processes for manufacturing the article according to the invention

Said composition is injected into an injection press. The transformation of said composition by injection consists of filling the cold cavities of a mold with said composition in the molten state, then demolding the part obtained after cooling and solidification of the plastic material.

The injection cycle is as follows:

Closure and locking of the mold;

Dosage of the material;

Injection of the melt into the mold;

Maintenance of the melt under pressure;

Opening of the mold; and ejecting parts.

The injection molding machine used to make test specimens is a Battenfeld HM 65/350. For the injection of fish boxes a larger injection molding machine is used, such as, for example, a BILLION H2100 / 400 injection molding machine.

The settings are set according to the composition. At the machine outlet the specimens are recovered.

In order to have a test tube of optimal quality, several parameters must be taken into account. Like extrusion, these criteria will depend on said composition to be injected. Regarding the temperatures, it is the injection and the mold that will be important for said composition to be melted when injected under pressure in the slurry and cexie this composition is ensune cooled by the mold to facilitate demolding .

The injection pressure and the maintenance of the composition are also important parameters for the material to take the desired shape and to be compact, which improves the quality of the product. If the pressure is too high, there will be burrs, if it is too weak, however, there will be a volume shrinkage.

The holding and cooling times allow time for the material to lower in temperature, so that it returns to below the crystallization temperature and ejects well from the mold at the end of the cycle.

Table 5

Currently, fish boxes are mainly injected with HDPE with application temperatures of between 200 and 280 ° C. Said composition having an operating temperature of between 180 and 195 ° C., the invention also relates to the reduction of environmental impacts during the implementation step with the reduction of the heating temperatures from 5 to 100 ° C. resulting in a reduction of the energy consumption of the machine and a reduction of the machine heating time as well.

Claims (14)

A biodegradable plastic composition, said composition comprising, by total weight of the composition: from 50% to 75% of a first bioplastic polymer, said first bioplastic polymer being poly (butylene succinate); from 1% to 25% of a second bioplastic polymer, said second bioplastic polymer being selected from the group consisting of polylactic acid, polyhydroxyalkanoate, and mixtures thereof; from 1% to 10% of a mineral filler; from 1% to 15% of a plasticizer compound; from 1% to 5% of a fatty acid; optionally a chain extender compound. The composition of claim 1 comprising a second bioplastic polymer, said second bioplastic polymer being polylactic acid; alternatively said second bioplastic polymer being polylactic acid without GMO. 3. Composition according to any one of the preceding claims, characterized in that the inorganic filler is calcium carbonate. 4. Composition according to any one of the preceding claims, characterized in that the plasticizer compound is selected from the group consisting of polyvinyl acetate and its derivatives; alternatively from the group consisting of ethylene vinyl polyacetate, polyvinyl acetate, and mixtures thereof; alternatively the plasticizer compound is ethylene vinyl polyacetate. 5. Composition according to any one of the preceding claims, characterized in that the fatty acid is chosen from the group consisting of unsaturated fatty acids; alternatively from the group of polymerized unsaturated fatty acids; alternatively the group consisting of unsaturated fatty acid dimers, unsaturated fatty acid trimers, and mixtures thereof. 6. Composition according to any one of the preceding claims, characterized in that the chain extending compound is selected from the group consisting of a multifunctional epoxy compound. 7. Composition according to any one of the preceding claims, comprising from 0.1% to 0.5% of said chain-extending compound, by total weight of the composition. A method of manufacturing a biodegradable plastic composition according to any one of the preceding claims, said process being selected from the group consisting of extrusion, injection, thermoforming, calendering, additive manufacturing processes, and their combinations; alternatively the process is an injection process. An article suitable for food contact comprising walls having an average thickness of at least 2 mm, said article being obtained from the biodegradable plastic composition according to any one of claims 1 to 7. 10. An article suitable for food contact, comprising walls having an average thickness of at least 2 mm, said article comprising, in total weight of said article: from 50% to 75% of a first bioplastic polymer, said first bioplastic polymer being poly (butylene succinate); from 1% to 25% of a second bioplastic polymer, said second bioplastic polymer being selected from the group consisting of polylactic acid, polyhydroxyalkanoate, and mixtures thereof; from 1% to 10% of a mineral filler; from 1% to 15% of a plasticizer compound; from 1% to 5% of a fatty acid; optionally a chain extender compound. 11. Article according to one of claims 9 to 10, said article being a tide box; alternatively said article being a fish crate. A method of manufacturing a food contactable article, comprising: providing a composition as claimed in any one of claims 1 to 7; injecting said composition into an article comprising walls having an average thickness of at least 2 mm. 13. Use of the article according to one of claims 9 to 11, for the storage or packaging of a product for food or feed; alternatively for the storage or packaging of a product of the sea; alternatively for storing or packaging a seafood product selected from the group consisting of fish, cephalopods, crustaceans, algae, and mixtures thereof; alternatively for storing or packing fish. 14. Use of the composition according to any one of claims 1 to 7 for the manufacture of articles suitable for food contact.