FR2986533A1 - Composition, useful as a softening agent for formulations based on biosources polymers and/or biodegradable polymers, comprises functionalized polyglycerol and polymer or copolymer grafted with maleic anhydride - Google Patents

Abstract

Composition comprises at least one functionalized polyglycerol and at least one polymer or copolymer grafted with at least one maleic anhydride. Composition comprises at least one functionalized polyglycerol having a structure of formulae (R1O-(CH 2-CH(OR2)-CH 2-O) n-R3) or (R1O-(CH 2-CH(CH 2(OR2))-O) n-R3) and at least one polymer or copolymer grafted with at least a maleic anhydride. R1-R3 : H or fatty acid chain; and n : >= 1. An independent claim is included for a formulation based on biosources polymer and/or biodegradable polymer, optionally charged with vegetable flour, where the formulation is present in an amount of 0.0001-20%.

Description

The present invention relates to a particular blend and its use as a softening agent in materials based on biosourced and / or biodegradable polymers, optionally loaded with vegetable flour (s). For several years, petrochemical materials used in many everyday applications, tend to be replaced by materials partially or completely biobased, and may have biodegradation functions. These include composite materials based on biosourced polymers and / or biodegradable optionally loaded with vegetable fari (s).

However, these biopolymer-based materials have a high rigidity which limits their use to applications requiring no flexibility. One solution considered to reduce the rigidity of the materials is to add to the polymers a softening agent that is to say an agent for generating a flexible product, resistant and easier to handle. The softening agents currently existing, however, are not usable in biomaterials. Indeed, they are either petrochemical phthalates, non-renewable, and non-biodegradable, or vegetable oil derivatives that migrate from the material, not compatible with biopolymers and resulting in performance losses. There is therefore a need for an agent for decreasing the rigidity of polymer-based materials, having excellent compatibility with biosourced and / or biodegradable polymers and preserving the performance of said materials. This is what the present invention provides by proposing the use as a softening agent for formulations based on biosourced and / or biodegradable polymers, a mixture of polyglycerol functionalized with a maleic polymer. Advantageously, such a use makes it possible to obtain formulations based on polymers having a low rigidity while being derived almost completely from natural resources, thus not harmful to the environment.

In particular, the invention relates to a composition comprising at least one functionalized polyglycerol corresponding to one of the following formulas: ## STR3 ## in which R 1, R 2 and R 3 represent hydrogen or chains of fatty acid, and n is an integer greater than or equal to 1, and a polymer or copolymer grafted with one or more maleic anhydride (s). The invention also relates to biopolymer-based materials comprising this composition. R10 R10 Surprisingly, such a composition has remarkable softening properties to decrease the rigidity of biopolymer materials, while the two individual compounds do not exhibit such an effect. The composition is also compatible with biopolymers and its use does not affect the performance of the materials in which it is used. Other features and advantages will become apparent from the detailed description of the invention which follows. The present invention thus aims at a composition comprising the mixture of at least one functionalized polyglycerol corresponding to one of the following formulas: CliR3 (1) n ClhR3 n OR2 (2) in which R1, R2 and R3 represent hydrogens or fatty acid chains, R1, R2 and R3 being identical or different, and n is an integer greater than or equal to 1, and a polymer or copolymer grafted with at least one maleic anhydride. By functionalized polyglycerol is meant a polyglycerol obtained by condensation of several glycerol units on themselves and for which part or the OR2 R10 R10 all hydroxyl groups has been replaced by other groups. Such a molecule corresponds to one of the following formulas (1) and (2) OR2 CliR3 (1) nCohR3 n OR2 (2) in which R1, R2 and R3 represent hydrogen or fatty acid chains, R1, R2 and R3 being identical or different, and n is an integer greater than or equal to 1. According to a preferred embodiment, the functionalized polyglycerol is a polyglycerol ester, in particular a polyglycerol ester functionalized with at least one acid functional group chosen from saturated fatty acids, monounsaturated fatty acids and polyunsaturated fatty acids.

Preferably, it is a polyglycerol ester having a degree of polymerization of 1 to 20 with one or more acid functional groups chosen from: saturated fatty acids, from C 1 to C 32, such as stearic acid and arachidic acid, mystic acid, caprylic acid, isostearic acid, etc. - monounsaturated fatty acids, such as palmitoleic acid, oleic acid, erucic acid, nervonic acid, and - acids polyunsaturated fats, such as linoleic acid, α-linoleic acid, γ-linoleic acid, di-homo-γ-linoleic acid, arachidonic acid, eicosapentaenoic acid, docosahexandic acid. R10 R10 According to another embodiment, the functionalized polyglycerol is an acetylated polyglycerol or an acetylated and esterified polyglycerol. By way of example, the polyglycerol polyricinoleate is a functionalized polyglycerol particularly suitable for the present invention.

By "polymer or copolymer grafted with one or more maleic anhydride (s)", also referred to by the generic term "maleic polymer" means a polymer or a copolymer of which at least one hydroxyl group has been replaced by a maleic anhydride. Preferably it is a polyolefin grafted with at least one maleic anhydride. It may be in particular a polypropylene grafted with at least one maleic anhydride, a polyethylene grafted with a maleic anhydride or copolyolefins grafted with at least one maleic anhydride. According to a particularly suitable embodiment, it is a polypropylene grafted with at least one maleic anhydride, corresponding to the following formula R 1 'P CH 3 (3) in which R 1' and R 2 'represent a methyl group or a carbon chain, R1 'and R2' being the same or different, and m and p are integers greater than or equal to 1, which are identical or different. The functionalized polyglycerol and the maleic polymer are present in the composition with a weight ratio polyglycerol functionalized / maleic polymer preferably between 0.1 and 10, in particular between 0.2 and 2.

According to a preferred embodiment, the composition according to the invention which is useful as a softening agent consists exclusively of a functionalized polyglycerol and of a maleic polymer, without any additional constituent. The composition as described above has properties enabling it to soften materials based on biobased and / or biodegradable polymers. It is the combination of the functionalized polyglycerol and the maleic polymer which has these properties, each of the constituents taken separately not having such an effect. The invention therefore relates to the use of a composition as described above, as a softening agent for formulations based on biosourced and / or biodegradable polymers. By way of example, the biobased and / or biodegradable polymers may be chosen from starch and starch mixtures, polypeptides, polyhydric alcohol, polyhydroxyal kanoates, hydroxybutyrates and polyhydroxyvalerates. polylactic acid and polylactates, polyamides 11 and their copolymers, biofouled polyolefins (polyethylene, polypropylene) cellulose, and polyesters. These polymers may be loaded with vegetable flour (s), in particular vegetable flour (s) chosen from: - starchy cereal flours, such as wheat flour, maize or rye flour, - flours proteins, such as faba bean, lupine, rapeseed, sunflower, soy or casein, and lignocellulosic flours, such as wood fiber, hemp or flax. The formulations based on biosourced and / or biodegradable polymers are: - materials consisting of a single type of biobased and / or biodegradable polymer, and / or - composite materials based on several biosourced and / or biodegradable polymer types, - Composite materials based on one or more biosourced and / or biodegradable polymer types loaded with vegetable flour (s). The use of a composition according to the invention makes it possible to improve the flexibility and the resistance of these formulations. In particular, it makes it possible to reduce their traction modulus and / or their maximum tensile stress which are higher than those of formulations based on polymers of petrochemical origin, while retaining the performance of the formulation. According to one particular embodiment, the use according to the invention consists in extruding a mixture of biodegradable polymers, optionally of vegetable flour (s), and of a mixture comprising at least one functionalized polyglycerol and a maleated polymer. , at temperatures between 50 and 300 ° C, more particularly between 150 and 250 ° C. Preferably, the weight content of softening agent (functionalized polyglycerol + maleic polymer) in the formulation is between 0.0001% and 20%. According to a last aspect, the invention also relates to formulations based on biobased and / or biodegradable polymers optionally loaded with vegetable meal comprising a mixture of functionalized polyglycerol and maleated polymer.

These formulations have a high flexibility due to the presence of the softening agent comprising the functionalized polyglycerol / maleic polymer mixture. Advantageously, the softening agent according to the invention has good compatibility with biopolymers or biopolymer-based formulations to be softened, and does not cause any loss of performance due to volatilization or exudation. These characteristics can be illustrated by the following example, made on composites based on polylactic acid (PLA) loaded with wood flour.

For this example: - the tensile characteristics of plastics were determined according to ISO / R 527 and ISO 178, - the deformation temperature under load (or I-11) T) was determined according to standard 15075, The melt flow index of the plastics follows the I50 1133 standard, and the resilience of the materials was determined according to I50 179 from untagged specimens. The operating protocol is described following.

Mixtures containing PLA, wood flour, Integrate NP507-30 (LyondellBasell) and polyglycerol polyricinoleate (PGPR) were extruded together using a Clextral BC21 corotative extruder (L = 600mm). L / c1 = 24) at 170 ° C. The products obtained by granulation are injected onto an Arburg 100T 25 press in order to form test pieces necessary for their mechanical characterization. The results obtained are presented in the following table which indicates the mechanical and rheological characteristics of the different materials: Table 1: Tests 1 to 6 with a wood flour content of 22.5% Test No. Integrate 0% 0% 0, 5 % 1% 2% 5% PGPR 0% 1% 1% 1% 1% 1% MFR (9 / 10min) 4 3 9 12 10 8 Constraint 64 56 42 39 34 32 maximum (MPa) Elongation at 2 2.0 2 , 5 2.8 3.5 3.3 rupture (%) 4450 module 3675 3375 3100 2800 2925 traction (MPa) HDT (° C) 55.5 52.9 52.2 52.7 51.6 52.7 Resilience 14 14 19 19 21 17 (KJ / m2) Table 2: Tests 7 to 10 with a wood flour content of 30% Test N ° 7 8 9 10 Integrate 0% 2% 2.7% 5% PGPR 1% 1% 1% 1% MFR (g / 10min) 5 3 6 3 Stress 57 31 31 28 maximum (MPa) Elongation at 1.7 2.9 2.4 2.9 rupture (%) Module of 4525 3450 3250 3300 tensile force (MPa) HDT (° C) Nd 54 N / A N / A Resilience (KJ / m2) 11 15 13 14 Nd = Not determined Table 3: Tests 11 to 14 with a wood flour content of 40% Test No. 11 12 13 14 Integrate 0% 2% 3.7% 5% PGPR 1% 1% 1% 1% MFR (g / 10min) 1 2 2 1 Stress 60 28 27 24 maximum (MPa) Elongation at 1.6 2.1 2.0 2.3 rupture (%) Module of 4775 4500 3750 3450 traction ( MPa) HDT (° C) Nd 55.6 Nd Nd Resilience (KJ / m2) 8 11 11 11 Nd = Not determined These results clearly show that the mixture of functionalized polyglycerol and maleic polymer according to the invention makes it possible to strongly reduce the modulus of traction and the maximum tensile stress of the material in which it is used. Without maleic polymer, the composite obtained has a high rigidity while with the mixture of functionalized polyglycerol and maleic polymer, the material has a high flexibility. It is also noted that the mixture of functionalized polyglycerol and maleic polymer, in addition to its softening role is compatible with the material in which it is introduced and keeps the mechanical properties of PLA, as well as its degradability in the natural environment.

Claims (13)

REVENDICATIONS1. A composition comprising at least: - a functionalized polyglycerol having one of the following formulas: OR2 R3 (1) wherein R1, R2 and R3 represent hydrogen or fatty acid chains, and n is an integer greater than or equal to 1, and a polymer or copolymer grafted with at least one maleic anhydride. 2. Composition according to claim 1, characterized in that the weight ratio polyglycerol functionalized / polymer or copolymer grafted with at least one maleic anhydride is between 0.1 and 10. 3. Composition according to claim 1 or 2, characterized in that the weight ratio polyglycerol functionalized / polymer or copolymer grafted with at least one maleic anhydride is between 0.2 and 2. 4. Composition according to one of the preceding claims, characterized in that the functionalized polyglycerol is a functionalised polyglycerol ester R10O R10 with at least one acid function chosen from saturated fatty acids, monounsaturated fatty acids and poly fatty acids. -unsaturated. 5. Composition according to one of claims 1 to 3, characterized in that the functionalized polyglycerol is an acetylated polyglycerol. 6. Composition according to one of claims 1 to 3, characterized in that the functionalized polyglycerol is an acetylated and esterified polyglycerol. 7. Composition according to one of the preceding claims, characterized in that the polymer or copolymer grafted with at least one maleic anhydride is selected from polypropylenes grafted with maleic anhydride, polyethylenes grafted with maleic anhydride and copolyolefins grafted with a maleic anhydride. maleic anhydride. 8. Use of a composition according to one of claims 1 to 7 as a softening agent for formulations based on biosourced polymers and / or biodegradable. 9. Use of a composition according to one of claims 1 to 7 to improve the flexibility and strength of formulations based on biobased and / or biodegradable polymers. 10. Use of a composition according to one of claims 1 to 7 for reducing the tensile modulus and / or the maximum tensile stress of formulations based on biosourced and / or biodegradable polymers. 11. Use according to one of claims 8 to 10, characterized in that the formulations based on biobased and / or biodegradable polymers are: - materials consisting of a single type of biobased and / or biodegradable polymer, and / or 25 - Composite materials based on several biosourced and / or biodegradable polymer types, composite materials based on one or more biosourced and / or biodegradable polymer types loaded with vegetable flour (s). 12. Use according to one of the preceding claims, characterized in that it consists in extruding a mixture of polymer (s) biodegradable (s) and / or biosourced (s) optionally loaded (s) vegetable (s) (s) (s) ( s) and a composition according to one of claims 1 to 7, at a temperature between 50 and 300 ° C. 13. Formulation based on biosourced polymer (s) and / or biodegradable (s) optionally loaded with vegetable meal (s), containing between 0.0001% and 20% of the composition according to the invention. one of claims 1 to 7.