WO2017055557A1

WO2017055557A1 - Composition comprising ground plants, maltodextrin and silicone

Info

Publication number: WO2017055557A1
Application number: PCT/EP2016/073431
Authority: WO
Inventors: Aurélie MOREL; Fabrice GARRIGUE
Original assignee: Evertree
Priority date: 2015-10-01
Filing date: 2016-09-30
Publication date: 2017-04-06
Also published as: FR3041966A1; FR3041966B1

Abstract

The present invention relates to a composition comprising ground plants containing proteins, maltodextrin and silicone. It also relates to an adhesive composition and articles comprising it, the preparation processes and uses thereof.

Description

COMPOSITION COMPRISING GROUND PLANTS, MALTODEXTRIN AND SILICONE

The present invention relates to a composition based on ground plants, and more particularly on oleaginous and/or proteaginous ground plants, process for obtaining same and uses thereof.

In recent years, the exploitation of oleaginous and proteaginous plants has developed considerably, in response to the needs of society.

Oleaginous and proteaginous plants are plants generally cultivated and exploited for their seeds or their fruits, which are particularly high in fats and proteins, respectively.

Among the oleaginous plants, sunflower, rapeseed, peanut, sesame, cotton, flax, castorbean, olive, oil palm, hazelnut, walnut, almond or also coconut may be mentioned. However, even though classed as "oleaginous", these plants also contain a significant content of proteins.

Soya, which is a proteaginous plant, is sometimes classified as oleoprot eaginous as it also produces oil. For this reason, it is often classed separately among the oleoproteaginous plants as it is high in both fats and proteins.

Among the proteaginous plants, pea (chickpeas, split peas), field bean and lupin, but also lentils, fenugreek and beans may be mentioned.

The oleaginous plants are mainly cultivated for their oil, used in different industries, such as human and animal food, lubricants, cosmetics, agronomy, in particular in the phytosanitary field, oil exploitation, materials or also the energy industry, for the production of biofuels such as biodiesel.

The conversion of the seeds or fruits of oleaginous plants to oil is generally carried out according to three main operations, which are:

- preparing the raw material to be extracted (seeds or fruits of an oleaginous plant): during its preparation, the raw material can be subjected to one or more of the following steps: cleaning or dedusting, sieving, shelling or hulling.

- crushing: this operation can comprise several steps depending on the raw material to be crushed. In all cases this operation comprises a step of grinding and extracting the oil contained in the raw material. - refining the oil, which consists of removing all or part of the compounds contained in an oil which make it unsuitable for use or subsequent conversion. For example, the refining of an oil intended for human consumption will generally comprise steps of neutralizing the taste, bleaching, deodorization, etc.

The crushing operation is a crucial operation for the conversion as it aims to extract the oil contained in the seeds or the fruits of the oleaginous plants.

This crushing operation therefore depends on the raw material from which it is sought to extract the oil. By way of example, in the case of seeds of oleaginous plants, the extraction carried out during the crushing is mainly based on two traditional techniques: the seeds called "high" in oil (>35%, for example sunflower or rapeseed) are crushed by pressure followed by chemical extraction while the seeds considered as "low" in oil (<35%, in the case of soya for example) are generally subjected to a chemical extraction.

By chemical extraction, is meant more particularly extraction with a solvent, such as an extraction with water or an organic solvent. When the extraction is carried out with an organic solvent, this step can be followed by a desolventizing step (step aimed at removing the solvents from a substrate, such as a plant meal).

For example, in the case of rapeseed or sunflower, the crushing operation comprises the following steps:

- rolling: this is a step of grinding the seeds. In general, these pass between two smooth cylinders and leave in a ground state, in the form of "flakes".

cooking: the objective of this step is to facilitate extraction of the oil contained in the seeds. In general, the flakes originating from the rolling are heated to approximately 80°C.

extracting the oil contained in the seeds: this step is generally carried out by pressing (or pressure) in presses.

All these steps can be carried out using a single machine exerting a continuous pressure while hot, i.e. the seeds are pre-heated to approximately 90°C, ground/rolled and then pressed in a screw-press where the temperature will reach up to approximately 120°C.

Two products are recovered at the end of this pressing step:

- on the one hand oil, generally described as "raw" or "pressed", and

- on the other hand, a first solid residue, namely press flakes or a fat-containing meal. The fat-containing meal generally comprises between 10 and 20% residual oil. In order to extract this residual oil present in the fat-containing meal, the crushing can comprise at the end of the pressing, a step of chemical extraction with a solvent. The solvent usually used for this extraction is hexane. The step of extraction with a solvent thus produces on the one hand the "residual' oil originating from the fat- containing meal, and on the other hand a second residue from the seeds, called defatted meal. The defatted meal generally comprises between 0.1 and 10%, preferably from 1 to 4% unextracted oil.

On the other hand, in the case of soya, the crushing operation essentially comprises the following steps:

rolling, and

extracting the oil contained in the seeds: this step is generally carried out by chemical extraction with a solvent.

At the end of the soya crushing operation, two products are recovered: the oil and the soya seed meal.

The meal is therefore a co-product of vegetable oil production. However, the valorisation of the plant meals by the oleaginous and/or oleoproteaginous industry has developed considerably over the last decades. In fact, as plant meal is very high in good quality proteins, it has considerably been used as a source of plant proteins in animal feed, as a substitute for or a complement to proteins of animal origin. But the use of the plant meals is not limited to these specific valorisation industries and has more recently been developed in other fields, in particular in the field of chemistry.

In this field, much research has been undertaken these last decades into what is called "green chemistry", the main objective of which is the use of more environmentally-friendly products, such as for example the use of products of renewable origin and the valorization of the co-products. Now, plant meals represent a bio-sourced product of the future due to their specific properties originating in particular from their remarkable content of proteins and pectins.

By way of example, it is known to use plant meals in the formulation of adhesive compositions for the manufacture in particular of composite wood boards. Application WO 201 1/156380 discloses in particular an adhesive composition based on proteins comprising a prepolymer such as a prepolymer based on polyisocyanate, and a protein component, which can be a ground plant meal, in a quantity sufficient to disperse the prepolymer in an aqueous medium. There is still a need for composite wood boards based on environmentally- friendly materials such as a ground plant meal, and having improved properties.

The work of the inventors has made it possible to demonstrate that the use of a particular ground plants composition makes it possible to improve the properties of the wood boards comprising said composition.

The invention therefore relates to a composition comprising:

ground plants containing at least 3% proteins, and

maltodextrin, and

silicone.

It will be noted that throughout the application, unless otherwise specified, the ranges of values indicated are understood to be endpoints inclusive.

By "ground plants containing at least 3% proteins" (also denoted "ground plants" hereafter), is meant a plant material formed into particles, following grinding and containing at least 3% by weight of proteins with respect to the total weight of ground plants. Preferably, the ground plants contain at least 10% proteins, more preferably at least 20%.

More particularly, the ground plants comprise between 3% and 60%, preferably between 5% and 60%, more preferably between 10% and 60%, even more preferably between 20% and 60% of proteins with respect to the total weight of ground plants.

More particularly, the ground plants comprise between 3% and 50%, preferably between 5% and 50%, more preferably between 10% and 50%, even more preferably between 20% and 50% of proteins with respect to the total weight of ground plants.

In particular, the cellulose content of the ground plants can be between 5 and 20% by weight of the total weight of ground plants.

The ground plants to which the invention relates can comprise particles that are insoluble in water.

Preferably, the ground plants containing at least 3% proteins are:

- a ground meal of one or more species of oleaginous plants (denoted "ground plant meal" hereafter),

- ground fruits and/or seeds of one or more species of ground proteaginous plant(s) (denoted "ground proteaginous plants" hereafter), or

- a mixture thereof.

Even more preferably, the ground plants are a ground plant meal.

The composition according to the invention makes it possible in particular to improve the properties of an adhesive composition and/or an article comprising it. In particular, the inventors demonstrated that the adhesive compositions and the articles based on lignocellosic materials comprising a composition according to the invention had improved properties such as gel time for the adhesive composition or mechanical strength and water swelling properties for the articles. The advantages of the composition according to the invention will be presented in more detail in the rest of the application and in the examples.

By "grinding", is meant any step aimed at obtaining a powder of plants, and more particularly a powder of plant meal. The grinding can comprise a pre-grinding and/or one or more fractionations of the homogenate.

The pre-grinding is a step mainly aimed at carrying out a first reduction in the form of particles of coarse size. This pre-grinding is generally followed by a fractionation step.

The purpose of the fractionation is to select a portion of the particles depending on their size and/or their chemical composition and can be carried out by various techniques such as sieving at a specific particle diameter, or also tribo-separation.

According to the invention, by "plant meal", is meant a fat-containing or defatted meal obtained at the end of a step of extraction (crushing, chemical extraction such as by solvent) of the oil contained in the seeds or the fruits of the oleaginous plants. Preferably, the meal is a defatted meal, originating from a crushing step followed by a step of extraction with a solvent.

Advantageously, the plant meal comprises a percentage of oil from 0.1 to 20%, preferably from 1 to 4% by weight of the total dry weight of plant meal.

By "maltodextrin", is meant a polysaccharide derived from the hydrolysis of starch. The derivatives of the hydrolysis of starch are generally defined by their dextrose equivalent (DE).

The DE corresponds to the quantity of reducing sugars expressed as a percentage of dextrose, also called D-glucose, with respect to the total dry weight of product. Generally, the DE is indicated by a figure or a number without indicating the unit (%). For example, dextrose, which corresponds to the product originating from the total hydrolysis of starch, is characterized by a DE equal to 100%, or 100. On the other hand non-hydrolyzed starch is characterized by a DE equal to 0. Maltodextrin is defined as a derivative of the hydrolysis of starch having a DE comprised between 0 and 20, endpoint 20 being included and endpoint 0 being excluded from the range.. As for the starch derivatives having a DE comprised in the range ]20;100[ they are called glucose syrups. The DE of maltodextrin can be measured according to the Lane and Eynon method.

Advantageously, the maltodextrin will have a DE comprised between 0 (excluded) and 13, preferably between 0.5 and 13, more preferably between 0.5 and 10, even more preferably between 1 and 6.

Apart from the DE, the maltodextrins can also be distinguished by their sugar composition, i.e. the nature and number of sugars of which they are composed. In fact, depending on the source of starch used (potato, maize, wheat), the type of hydrolysis implemented (chemical or enzymatic hydrolysis) or also depending on the hydrolysis conditions, this sugar composition can vary.

Advantageously, the maltodextrin used in the composition according to the invention will have good characteristics of dispersion and solubility in water.

Maltodextrins which can be used in the context of the present invention are for example the maltodextrins marketed by the company ROQUETTE® under the trade mark GLUCIDEX®.

By "silicone" (also called "polysiloxane" or "siloxane"), is meant oligomers, polymers or co-polymers comprising an inorganic backbone comprising one or more alternate silicon-oxygen chain(s), each chain being optionally substituted on the silicon atoms by organic groups. Organic groups which are reactive or unreactive can thus be grafted at the end of the chain and/or laterally on the main backbone.

Advantageously, the silicone is a polymer based on polydimethyl siloxane. Preferably, the silicone is a polyether - polydimethyl siloxane copolymer.

Preferably, the quantity of maltodextrin in the composition is comprised between 0.1 and 20%, more preferably between 0.5 and 10%, yet more preferably between 1 and 4% by dry weight with respect to the total dry weight of the meal.

Preferably, the quantity of silicone in the composition is comprised between 0.5 and 30%, more preferably between 5 and 20%, yet more preferably between 8 and 15% by dry weight with respect to the total dry weight of the meal.

According to a first embodiment of the invention, the ground plants in the composition is one or more ground plant meal(s) chosen from the group consisting of meals of rapeseed, canola, sunflower, soya, cotton, flax, walnut, olive, mustard, hemp, oilseed poppy, safflower, kapok, maize germ, rape, shea, sesame, castorbean, camelina, jatropha, peanut, palm oil kernels, hazelnut, almond and copra. Oilseed poppy is also known as papaverum somniferum nigrum . Copra is the dried raw material used for the extraction of coconut oil. At the end of this extraction, a copra meal is obtained.

Advantageously, the ground plant meal(s) is (are) chosen from the group consisting of rapeseed, canola, sunflower, soya and castorbean meals.

Preferably, the ground plant meal is a rapeseed or canola meal.

According to a second embodiment of the invention, the ground plants in the composition are obtained by grinding fruits and/or seeds of proteaginous plants chosen from the group consisting of pea, field bean, lupin, lentils, fenugreek and beans.

Preferably, the proteaginous plants are chosen from the group consisting of pea, field bean and lupin.

According to the first embodiment of the invention, the ground plant meal in the composition is in the form of a powder having a median-volume diameter D₅₀ comprised between 1 and 250 μηη.

The median-volume diameter D₅₀ is a characteristic known to the skilled person.

This diameter makes it possible to characterize a particle size distribution of a powder and corresponds to the diameter for which 50% of the total volume of the particles has a diameter of less than D₅₀.

Preferably, the ground plant meal is in the form of a powder having a median- volume diameter D₅₀ comprised between 5 and 100 μηη, more preferably between 10 and 75 μηη, yet more preferably between 15 and 50 μηη, yet more preferably between 20 and 40 μπι.

The volume diameter D₉₉ can also be used to characterize a particle size distribution of a powder. The diameter D₉₉ is defined in a similar manner to the powder median-volume diameter D₅₀ and corresponds to the diameter for which 99% of the total volume of the particles has a diameter of less than D₉₉.

Preferably, the ground plant meal is in the form of a powder having a volume diameter D₉₉ comprised between 40 and 300 μηη, preferably comprised between 70 and 180 μηη, more preferably comprised between 80 and 140 μηη.

This particle size distribution is also that preferred for all the other types of ground plants envisaged according to the invention.

Regardless of the embodiment, the composition according to the invention is advantageously in the form of granulates. When the pellet is prepared from a meal, the term "coated meal" may also be used.

Particularly, the invention relates to a composition comprising: between 65 and 99.4% by weight of ground plants comprising at least 3% by weight of proteins with respect to the total weight of ground plants,

between 0.1 and 15% by weight of maltodextrin, and

- between 0.5 and 20 % by weight of silicon,

wherein the % by weight are indicated with respect to the total weight of the composition unless otherwise specified.

More particularly, the invention relates to a composition comprising:

between 75 and 95 % by weight of ground plants comprising at least 3% by weight of proteins with respect to the total weight of ground plants, between 1 and 10% by weight of maltodextrin, and

between 4 and 15% by weight of silicon,

The invention also relates to a process for the preparation of a composition according to the invention, comprising the following steps:

(i) grinding the seeds and/or fruits of oleaginous and/or proteaginous plants,

(ii) the addition of maltodextrin and silicone to the ground plants obtained in step

(i)- By "grinding", is meant any step aimed at obtaining a powder of plants, and more particularly a powder of plant meal. More particularly, the powder originating from this grinding has a median-volume diameter D₅₀ comprised between 1 and 250 μηη.

Preferably, the grinding is carried out so as to obtain a powder the median- volume diameter D₅₀ of which is comprised between 5 and 100 μηη, preferably comprised between 10 and 75 μηη, more preferably comprised between 15 and 50 μηη, and yet more preferably comprised between 20 and 40 μηη.

Alternatively, the grinding can be carried out so as to obtain a powder the volume diameter D₉₉ of which is comprised between 40 and 300 μηη, preferably between 70 and 180 μηη, more preferably between 80 and 140 μηη.

A particularly suitable grinding mill for carrying out the grinding step according to the process of the invention is a knife mill of the attrition type.

Preferably, the grinding is carried out on a plant meal and is carried out so as to limit the heating of said meal. For this purpose, the grinding is carried out at a temperature less than 100°C, preferably less than 80°C, more preferably less than 60°C. Throughout the application, the temperatures and pressures are indicated under normal temperature and pressure (NTP) conditions.

The grinding can, optionally, be preceded by pre-grinding.

The pre-grinding is a step aimed mainly at carrying out a first reduction in the form of particles. More particularly, by pre-grinding is meant any step making it possible to obtain a powder, such as a powder of plant meal, having a median-volume diameter D₅₀ comprised between 250 and 450 μηη.

This pre-grinding is preferably followed by a fractionation step. In general, this fractionation is a sieving (also denoted "screening" in this particular case). This sieving is preferably carried out at a diameter approximately equal to the median-volume diameter D₅₀ as defined during the pre-grinding step for recovering the fines having a diameter less than the median-volume diameter and the oversize particles having a diameter greater than the median-volume diameter.

In the case of a plant meal, this pre-grinding followed by screening (or sieving) makes it possible to separate a fraction high in proteins (used for the preparation of the ground meal) from a fraction low in proteins (i.e. the oversize particles).

At the end of the optional pre-grinding and screening, grinding is carried out. This grinding can also be followed by a fractionation step. Such fractionation can be carried out by a cyclone.

Other fractionation technologies by dry or wet route can equally well be applied, such as tribo-separation.

By way of example, the application WO2015/097290 describes a process for the tribo-separation of a plant meal.

According to a preferred embodiment of the process according to the invention, the addition of maltodextrin and silicone performed in step (ii) is carried out by preparing at least one aqueous solution comprising maltodextrin and/or silicone.

The aqueous solution can be prepared from any type of water, such as a tap water, a demineralized, deionized and/or distilled water. The pH of the water is thus comprised between 5 and 9, preferably between 6 and 8, more preferably the pH is neutral (around or equal to 7).

Advantageously, the aqueous solution comprises maltodextrin. This solution comprises maltodextrin at a content comprised between 1 and 40% by dry weight of maltodextrin with respect to the total weight of water, preferably between 10 and 30% by dry weight of maltodextrin with respect to the total weight of water, yet more preferably between 15 and 25% by dry weight with respect to the total weight of water. The aqueous solution of maltodextrin can also comprise silicone. This solution then comprises silicone at a content comprised between 30 and 80% by dry weight of silicone with respect to the total weight of water, preferably, between 40 and 70% by dry weight of silicone with respect to the total weight of water, yet more preferably between 55 and 65% by dry weight with respect to the total weight of water.

The total weight of water of the aqueous solution is defined as the total weight of water introduced into the solution, without taking account of the water inherently comprised in the ground plants, the maltodextrin or any other ingredient introduced into the solution other than water.

The aqueous solution can also comprise other ingredients, such as urea. By way of example, the urea content in the aqueous solution is comprised between 0.01 and 40% by weight with respect to the total weight of water.

According to a first variant of the preferred embodiment, the aqueous solution is sprayed onto the homogenate obtained in step (i).

Preferably, the spraying is carried out with an aqueous solution comprising both maltodextrin and silicone.

Alternatively, two sprayings can be carried out, on the one hand with the aqueous solution of maltodextrin and on the other hand with the silicone. In this case, the silicone is preferably sprayed before the aqueous solution of maltodextrin.

Advantageously, the spraying is carried out under vacuum. Preferably, the spraying system is provided with a full conical nozzle in order to ensure a better dispersion of the droplets.

Drying of the ground plants can then be carried out a temperature of the order of 20 to 70°C, preferably of the order of 40 to 60°C.

At the end of this drying, a pellet of ground plants is obtained (coated with maltodextrin and/or silicone), having a moisture content of the order of 1 to 12% by weight, preferably of the order of 5 to 7%.

According to a second variant of the preferred embodiment, the ground plants obtained in step (i) are placed in suspension in the aqueous solution.

Preferably, the ground plants obtained in step (i) are placed in suspension at a content comprised between 30 and 80%, more preferably between 40 and 70%, yet more preferably between 55 and 65% by dry weight with respect to the total weight of water and homogenate.

More particularly, the ground plants obtained in step (i) are placed in suspension in an aqueous solution containing maltodextrin. This aqueous solution containing maltodextrin can advantageously comprise urea.

In this case, the silicone is added to the aqueous suspension containing the homogenate obtained in step (i), the maltodextrin and optionally the urea.

The invention also relates to an adhesive composition comprising a composition according to the invention, and one or more precursors of a resin chosen from the group consisting of polymethylene diphenyl 4,4'-diisocyanate, urea-formaldehyde, phenol-formaldehyde and/or melamine-urea-formaldehyde.

By "precursor of a resin" is meant a component or mixture of components making it possible to obtain said resin after a polymerization step.

The use of a composition according to the invention makes it possible to reduce the gel time of the adhesive composition according to the invention, as described in Examples 2 and 3 and in Figure 2.

Polymethylene diphenyl 4,4'-diisocyanate is also known as pMDI, urea- formaldehyde as UF, phenol-formaldehyde as PF and melamine-urea-formaldehyde as MUF.

Preferred mixtures of resins are pMDI and UF on the one hand and pMDI and PF on the other hand.

The adhesive composition according to the invention can also comprise urea, a water-repellent agent such as wax.

By "water-repellent agent", is meant any substance the role of which is to prevent or reduce the contact of water with, or its penetration into, a material.

More generally, the adhesive composition according to the invention can comprise one or more agents chosen from the group consisting of:

- formaldehyde-trapping agents or cross-linking agents such as urea, phenol,

catalysts,

bonding agents,

fillers such as calcium carbonate, clay,

- thickeners or texturizing agents or also gelling agents,

surfactants such as siloxanes,

adhesion promoters such as a polyol, for example in the case where the resin introduced into the composition is based on isocyanate,

- antioxidants such as polyphenols, antifoaming agents,

antimicrobial agents such as oxidants,

antibacterial agents such as nitrogen derivatives,

fungicides such as sulphur-containing products,

- preservatives such as citric acid, paraben,

pigments such as titanium dioxide,

agents improving moisture resistance or water-repellent agents such as wax,

pH modulators such as urea,

- anti-adhesive or composite release agents, and

fire-resistant agents.

A solid binder can be also prepared from the adhesive composition according to the invention by polymerization thereof. Advantageously, the polymerization is carried out by thermosetting. The curing temperature is generally comprised between 100 and 300°C, more preferably between 140 and 250°C.

The invention also relates to an article comprising an adhesive composition according to the invention and a lignocellulosic material.

By "lignocellulosic material", is meant more particularly paper, cardboard, wood strands, wood veneer, wood particles, wood fibres. The wood particles can be chips, sawdust or any other waste based on wood originating from a sawmill.

The use of a composition or an adhesive composition according to the invention makes it possible to improve the properties of the article(s) based on lignocellulosic material(s) comprising them. In particular, these articles have an increased stress resistance and a reduced swelling rate, with respect to articles comprising a composition or an adhesive composition based on ground plants alone, ground plants and maltodextrin, or ground plants and silicone. These advantages are given in greater detail in Example 3 and Figure 3.

Advantageously, the article according to the invention is a lignocellulosic composite board. A lignocellulosic composite board is a combination of lignocellulosic materials and an adhesive composition called a matrix, wherein the lignocellulosic materials and the matrix keep their identity, do not dissolve or do not mix completely. For that reason, they can be physically identifiable on a macroscopic scale.

More particularly, the article is made of glued-laminated wood, plywood or a composite wood board such as a laminated board or oriented strand board (OSB), a particleboard or chipboard, or a fibreboard. The invention also relates to a process for the manufacture of an article according to the invention. Advantageously, the process comprises the following steps:

(i) bringing a lignocellulosic material into contact with the adhesive composition according to the invention, and

(ii) heating the adhesive composition so as to cure it.

The curing temperature is generally comprised between 100 and 300°C, more preferably between 140 and 250°C. The curing time is less than 10 min; preferably less than 5 min. Preferably, heating the adhesive composition so as to cure it, is carried out by thermo-pressing (step of concomitant heating and pressing).

Advantageously, the lignocellulosic material is wood particles. These are then brought into contact with the adhesive composition according to the invention. This bringing into contact can be carried out by mixing wood particles with the composition according to the invention or alternatively by spraying the composition according to the invention onto the wood particles. The wood particles thus brought into contact with the adhesive composition according to the invention are then placed in a mould, pressed and heated in order to cure the adhesive composition.

More particularly, a particleboard is usually manufactured according to the following process:

Preparing the raw lignocellulosic material (grinding, grading, drying),

Mixing with the adhesive composition,

Forming of the particle mat,

Thermo-pressing, and optionally,

Finishing the boards.

Finally, the invention relates to the use of a composition according to the invention for the preparation of an adhesive composition, a polyurethane foam, a cosmetic composition, a phytosanitary composition, or a food composition.

Preferably, the adhesive composition is an adhesive composition for a lignocellulosic material, such as wood-based materials.

By way of example, the characteristics of these wood-based materials, such as wood boards, and their manufacturing process are more fully described above and in Example 3.

By "phytosanitary composition", is meant more particularly a composition for the protection of crops. Preferably, the food composition is a food composition for animals, such as a food composition for aquaculture.

The invention will be better understood in the light of the following examples, given by way of illustration, with reference to:

- Figure 1 , which shows the typical profile of particle size distribution measured in the dry state on the powder of a ground plant meal (for example, rapeseed, sunflower, soya etc.);

Figure 2, which shows a diagram illustrating the effect of the introduction of maltodextrin and/or silicone on the gel time of an adhesive composition,

- Figure 3, which shows diagrams illustrating the effect of the introduction of maltodextrin and/or silicone on the properties of a pressed wood board, in particular, the mechanical strength (maximum 3-point bending stress (MPa) Fig. 3A) and the water swelling rate of a pressed wood board (in % increase in thickness) after immersion for 24 hours(Fig. 3B); and

- Figure 4, which shows diagrams illustrating the effect of the chemical nature of silicone on the properties of a pressed wood board, in particular, the mechanical strength (maximum 3-point bending stress (MPa) Fig. 4A) and the water swelling rate of a pressed wood board (in % increase in thickness) after immersion for 24 hours(Fig. 4B).

Other characteristics and advantages of the invention will become apparent in the following examples, given by way of illustration.

Example 1 : Composition according to the invention in granulate form.

1. Materials

1 .1 . Meal

The rapeseed meal used in this example was supplied by Saipol (Grand Couronne site, France). This meal was obtained by a hot pressure step, followed by a step of extraction by organic solvent (i.e. hexane) of the pressed flakes (which denote the product obtained at the end of the hot pressure step) in order to extract the vegetable oil.

By hot pressure step is meant a step comprising a preheating of the rapeseeds up to 90°C, then a grinding of said seeds and pressing in a screw-press where the temperature can reach up to 120°C. A fat-containing meal is then obtained comprising 12% to 14% residual oil.

Finally, the step of extraction by organic solvent is followed by a desolventizing step. The rapeseed meal thus obtained generally contains 1 to 2% residual oil for 10 to 12 % moisture.

1 .2. Maltodextrin

The maltodextrin is of the trade mark Glucidex® 1 (DE<6%) from Roquette®. This maltodextrin is in the form of a white powder with a maximum moisture content of 6% by weight.

1 .3. Silicone

The silicone is a polymer based on polydimethyl siloxane supplied by Evonik® (Germany), namely Tegostab® B 8460 (polyether - polydimethyl siloxane copolymer).

1 .4. Water

The water is a demineralized water. However, tap water could be used. In fact, a test was carried out with tap water and no effect was observed on the properties of the compositions, compared to a test using demineralized water. 2. Method

2.1 . Grinding of the rapeseed meal

The rapeseed meal supplied by Saipol was ground using an 1 1 kW ATTRIMILL (Poittemill) grinding mill, making it possible to obtain flow rates between 10 and 300 kg/h of fine particles. The flow rate obtained with the grinding mill is the result of regulating the actuation of the feed screw of the grinding mill as a function of the amperage consumed. The screw operates until the electrical consumption of the grinding mill exceeds the limit of 19 amperes (A). Once this limit has been exceeded, the screw stops and restarts automatically, once the amperage falls below the limit of 18 A. This "ping pong" system lasts whilst there is product in the feed hopper of the grinding mill. This grinding mill is provided with a dynamic cyclone making it possible to carry out a particle size classification and a selection of the particles according to their size.

In practice, the settings are the following:

o grinding mill speed of 4880 rpm,

o dynamic cyclone at 10 Hz.

During the grinding, care must be taken that the heating of the meal is limited. To this end, the temperature of the air leaving the filter of the grinding mill was controlled so as not to exceed 60°C. The air passing through the grinding mill was drawn in from the test center, the temperature of which was 20°C for the entire duration of the grinding. The installation (grinding mill and cyclone) was cleaned between each grinding.

The yield of this operation (grinding and cyclone) is greater than 99%.

The rapeseed meal obtained then has the following particle size distribution profile:

- D₅₀ (median-volume diameter) <40 μηη,

D₉₉<140 μηη.

More particularly, the grinding and the selection of the particles of the meal by cyclone are aimed at obtaining a particle size distribution profile shown in Figure 1.

The grinding step described above can, optionally, be preceded by a step of pre-grinding the meal to a coarse granulometry having a median-volume diameter D₅₀ of approximately 250 to 450 μηη. This pre-grinding is followed by a sieving (or screening) step at a diameter corresponding to the D₅₀ in order to separate the fines having a diameter less than the diameter of the oversize particles (i.e. the particles with a diameter greater than D₅₀). This upstream process makes it possible to separate a fraction high in proteins (i.e. the particles with a diameter less than D₅₀) from a fraction low in proteins (i.e. the particles with a diameter greater than D₅₀). Other technologies for the selection of particles can also be applied. For example, a fractionation by dry route such as tribo-separation or by wet route such as precipitation from a solvent under given physico-chemical conditions can equally well be carried out.

2.2. Measurement of the granulometry of the particles of rapeseed meal obtained

The median-volume diameter D₅₀ of the rapeseed meal obtained at the end of the grinding step was measured in the dry state. The granulometry of the particles of ground rapeseed meal was characterized using a HELOS laser granulometer of the WINDOX 5 type. The measurement range is from 0.5 to 875 μηη.

The characteristics of the granulometry measurement are the following:

o Feed rate of 50%,

o Measurement cycle of 100 ms,

o Pressure of 1 bar.

3. Preparation of a composition according to the invention, by granulation

The ground meal is incorporated at ambient temperature into a De Dietrich mixer provided with a double jacket and a spray system. This mixer is stirred at 140 rpm. A solution of maltodextrin in water at 10% by dry weight of maltodextrin with respect to the total weight of water and maltodextrin (i.e. 1 1.1 1 % by dry weight of maltodextrin with respect to the total weight of water) is prepared under mechanical stirring using a four-blade propeller (approximately 400 rpm) over approximately 1 minute.

The silicone is added to the aqueous solution of maltodextrin at a content of 55% by dry weight with respect to the total weight of water and maltodextrin (i.e. 61.1 1 % by dry weight of silicone with respect to the total weight of water).

The solution containing the maltodextrin and the silicone is then tempered preferably at a temperature comprised between 45 and 51 °C in order to ensure better solubilization, then pumped and sprayed into the stirred mixer at atmospheric pressure. A vacuum is then created in the stirred mixer and is achieved in two to three minutes (70 - 100 mmHg). Then, the set temperature of the double jacket of the mixer is progressively increased to 60°C. The test is ended when the moisture of the powder is comprised between 3 and 6% by weight (corresponding to a temperature of the powder between 52 and 57°C). The water content is monitored during the drying process. A maximum water content of the granulated meal of 6% was chosen in order to retain the specification given for that of the maltodextrin alone.

The pellet thus obtained can easily be placed in suspension in water. In order to facilitate this placing in suspension, the pellet can undergo a sieving operation, for example at 250 μηη, prior to its introduction into the water.

Example 2: Preparation of a composition according to the invention and comparative compositions

1. Materials

1 .1 . Meal

The rapeseed meal used in this example is identical to that in Example 1.

1 .2. Maltodextrin

The maltodextrin is that described in Example 1.

1 .3. Silicone

The silicone is the polymer based on polydimethyl siloxane described in Example 1.

1 .4. Water

The water is that described in Example 1. 1 .5. Petrochemical resins

The resin used for the preparation of the adhesive composition is a urea- formaldehyde resin, DYNEA®, having a dry extract of 65%. Three types of resins were tested: pMDI (polymethylene diphenyl 4,4'-diisocyanate, BAYER, purity of 99%), UF (Urea-Formol, DYNEA, dry extract of 65%) and PF (Phenol-Formol, DYNEA, molar ratio PF/ hardener = 1.67, dry extract of 100%).

1 .6. Urea

The urea is the urea U5378 from Sigma Aldrich, USA.

1 .7. Wax

The wax used is the waterproofing agent MS27 supplied by ICABOIS. Its dry extract is 58%.

2. Method

2.1 . Grinding the rapeseed meal and measuring the qranulometry of the particles of rapeseed meal obtained

Grinding the rapeseed meal and measuring the granulometry of the particles of rapeseed meal obtained are carried out as indicated in Example 1 .

2.2. Preparation of the compositions

The adhesive compositions were prepared at ambient temperature. Their mixing was carried out mechanically using a four-blade propeller at a variable speed of 400 to 1200 rpm.

a) Composition according to the invention 4c (with maltodextrin and silicone)

Urea and maltodextrin are added to water at respective concentrations of 1 g.L^"1 and 57 g.L^"1 then solubilized under stirring (approximately 400 rpm) over approximately 1 minute.

Ground rapeseed meal is then added to the water-urea-maltodextrin mixture over approximately 3 minutes by successively adding small quantities, at a stirring speed ranging from 400 to 500 rpm depending on the increase in viscosity (i.e. when a fresh quantity of ground meal is added, the stirring speed is increased to 500 rpm), until a homogeneous suspension is obtained. The quantity of meal added by weight with respect to the total weight of water and meal is 25% w/w.

Then, the silicone is added at 500 rpm, 1 1 % by weight with respect to the total weight of ground meal. This suspension of ground meal in aqueous medium is then mixed with a urea- formaldehyde resin, added continuously under very vigorous stirring (approximately 1200 rpm), at a quantity of 93.92 g per 100 g of adhesive composition, the weights being given in dry weight.

Stirring is maintained for 2 to 3 minutes in order to homogenize the mixture well.

The dry extract content of the adhesive composition is finally adjusted so that the viscosity of the adhesive formulation remains constant compared to that measured on an adhesive formulation without meal.

b) Comparative composition 4d (with silicone only)

Urea is added to water at a concentration of approximately 1 g.L^"1 then solubilized under stirring (approximately 400 rpm) over approximately 1 minute.

Ground rapeseed meal is then added to the water-urea mixture over approximately 3 minutes by successively adding small quantities, at a stirring speed ranging from 400 to 500 rpm depending on the increase in viscosity (i.e. when a fresh quantity of ground meal is added, the stirring speed is increased to 500 rpm), until a homogeneous suspension is obtained. The quantity of meal added by weight with respect to the total weight of water and meal is 25% w/w.

Then, the silicone is added at 500 rpm, at a quantity of 1 1 % by weight with respect to the total weight of meal. This suspension of ground meal in aqueous medium is then mixed with a urea-formaldehyde resin, added continuously under very vigorous stirring (approximately 1200 rpm), at a quantity of 94.01 g per 100 g of adhesive composition, the weights being given in dry weight.

Stirring is maintained for 2 to 3 minutes in order to thoroughly homogenize the mixture.

c) Comparative composition 4e (with maltodextrin only)

Urea and maltodextrin (DE<6) are added to water at respective concentrations of 1 g.L^"1 and 57 g.L^"1 then solubilized under stirring (approximately 400 rpm) over approximately 1 minute.

This suspension of ground meal in aqueous medium is then mixed with a urea- formaldehyde resin, added progressively under very vigorous stirring (approximately 1200 rpm). The quantity of resin added is 94.43 g per 100 g of adhesive composition, said quantities being expressed in dry weight.

d) Comparative composition 4b (with neither maltodextrin nor silicone)

This homogeneous suspension of ground meal in water is then mixed with a urea-formaldehyde resin, added progressively under very vigorous stirring (approximately 1200 rpm). The quantity of resin added is 89.35 g per 100 g of adhesive composition, said quantities being expressed in dry weight.

When this composition is used as an adhesive composition, wax is added to this composition. e) Summary table of the compositions

Table 1 : Summary of compositions 4b to 4e expressed as a percentage by dry weight of each ingredient with respect to the total dry weight of the composition.

2.3. Characterization of the compositions obtained

Compositions 4b to 4e can be used as adhesive compositions and are characterized by:

Measurement of the dry extract using a halogen balance (105°C, stabilization time of 20 seconds),

Measurement of a flow time using the Lory Elcometer 2215 viscosity cup (non-standardized test),

Measurement of the gel time by monitoring the change in viscosity with a Trombomat (test temperature 180 to 200°C, this range of temperatures corresponding to those implemented during the heating of a composite wood board).

3. Results

The results of the measurements of viscosity and gel time of the compositions are presented in Table 2 below and in Figure 2.

* Vcu: Viscous Coupling Unit

Table 2: Viscosity and gel time of the compositions (without wax for test 4b).

As may be noted in Figure 2, the gel time of the adhesive composition is significantly reduced with the introduction of maltodextrin and little affected with the introduction of silicone. However, a synergistic effect of reduction in the gel time of the composition is observed with the introduction of maltodextrin and silicone.

The reduction in the gel time may result in a premature pre-curing of the resin. An expected benefit of this accelerated curing of the resin is a limitation of the temperature drop experienced during the drying at temperature. This effect makes it possible in particular to reduce the filtration of the adhesive composition through the material coated with this composition, for example through the pores of the wood particles. The adhesive composition thus remains more on the surface, for example of the wood particles and can better ensure its role as binder.

Example 3: Preparation of pressed wood boards

Pressed wood boards were prepared on a laboratory scale from adhesive compositions prepared in similar ways to those of Example 2. For reasons of dimensioning, the boards were prepared in one layer, based on fine chips (corresponding to the inner layer of a standard board).

1. Materials

1 .1 . Adhesive compositions

The adhesive compositions 1 c to 1f utilized in this example are prepared in identical ways to the compositions 4b to 4e respectively, prepared in Example 2.

Compositions 1 a and 1 b are prepared from UF resin and optionally water and ground rapeseed meal as described in the materials of Example 2. The preparation of these compositions is described more fully below.

1 .2. Wood particles

The fine particles (in the present case, chips) of wood originate from Kron of ranee.

2. Method

2.1 . Preparation of composition 1 a

The UF resin is mixed with the wood chips. To this end, the latter is generally sprayed onto the wood chips in a mixer. However, during these tests, the resin was manually mixed with the wood chips.

When this composition is used as an adhesive composition, wax is added to this composition. This addition is carried out manually after mixing the resin and the wood chips.

2.2. Preparation of composition 1 b

Ground rapeseed meal is then added to the water over approximately 3 minutes by successively adding small quantities, at a stirring speed ranging from 400 to 500 rpm depending on the increase in viscosity (i.e. when a fresh quantity of ground meal is added, the stirring speed is increased to 500 rpm), until a homogeneous suspension is obtained. The quantity of meal added by weight with respect to the total weight of water and meal is 25% w/w.

This suspension of ground meal in aqueous medium is then mixed with a urea- formaldehyde resin, added progressively under very vigorous stirring (approximately 1200 rpm).

Summary table of adhesive compositions 1 a to 1f

Table 3: Summary of adhesive compositions 1 a to 1f expressed as a percentage by dry weight of each ingredient with respect to the total dry weight of composition.

2.4. Characterization of the compositions obtained

Adhesive compositions 1 a to 1f were characterized by:

Measurement of the dry extract,

Measurement of a flow time,

- Measurement of the gel time,

as described in Example 2.

2.5. Drying the wood chips

The oven used is a conventional oven with ventilation.

The chips are placed in an oven at 60°C in aluminium trays containing approximately 100 g (which facilitates placing the chips in the oven). They are left for a minimum of 6 hours at this temperature. The dry extract of the chips used for the composition wood boards is 97% (measured on a dry extract balance).

The chips are left in the oven until use. They are taken out of the oven shortly before production of the wood board (approximately 10 to 15 minutes maximum in order to avoid re-uptake of moisture in the particles, which corresponds to the time it takes to cool).

2.6. Preparation of the pressed wood boards

The boards were prepared in the following way:

(i) Manual mixing of the wood chips (after cooling subsequent to taking them out of the oven) with one of the adhesive compositions 1 a to 1 f at a temperature of 30 to 35°C for 2 min;

(ii) For adhesive compositions 1 a to 1 c, the addition of wax to the mixture obtained in step (i) and manual mixing for 1 min;

(iii) Incorporation of the mixtures obtained in steps (i) (mixture starting with the adhesive compositions 1 d to 1f) and (ii) (mixture starting with adhesive compositions 1 a to 1 c) in a mould the dimensions of which have been calculated in order to be able to set the density of the board at 650 kg/m³ (the boards obtained measure approximately 250 x 350 mm² for a final thickness of 7-8 mm);

(iv) Incorporation of the moulds containing the mixtures in a MI41 press from TechniHispania at 200°C for 4 minutes.

2.7. Summary table of the wood boards obtained from adhesive compositions 1 a to 1 f

* % by dry weight with respect to the total dry weight of the pressed wood board

Table 4: Summary table of the compositions of the wood boards obtained from adhesive compositions 1 a to 1 f.

2.8. Characterization of the pressed wood boards

The pressed wood boards are characterized by two parameters: Swelling in water: the measurement of swelling in thickness of the wood board after total immersion in water (according to standard NF EN 317) is carried out at ambient temperature, the thickness measurements being carried out at tO, t+2 hours, t+24 hours, on average on 3 samples.

- Mechanical strength: the measurement is carried out by a 3-point bending test intended to assess the maximum stress, and the bending modulus (MPa). This measurement is based on the standard NF EN 310 and is carried out on a machine of the MTS Criterion (model 43) load frame type, with a 2 kN sensor, test speed 2 mm/min, on average on 5 samples.

The standards as stated in this application are those current at the date of filing.

3. Results

3.1. Results on the adhesive compositions

The results of the measurements of viscosity and gel time of the compositions presented in Table 5 below.

* Vcu: Viscous Coupling Unit

Table 5: Viscosity and gel time of adhesive compositions 1 a to 1f (without wax for tests a, b and c).

The gel time of the adhesive composition is:

significantly reduced with the introduction of meal and maltodextrin, and little affected with the introduction of urea.

A synergistic effect of reduction in the gel time of the composition is observed with the introduction of the maltodextrin and the silicone.

3.2. Results on the pressed wood boards

The results in terms of swelling in water and mechanical strength are given in Table 6 below and in Figure 3.

1d 1.19+/-0.10 34+/-3 35+/-3

1e 0.84+/-0.08 37+/-4 40+/-6

1f 0.84+/-0.10 45+/-5 42+/-4

Table 6: Mechanical properties and water resistance of the pressed wood boards prepared using adhesive compositions 1 a to 1f.

The mechanical properties of the pressed wood board are markedly improved when the latter is prepared with adhesive composition 1 d, i.e. with the adhesive composition comprising a maltodextrin and a silicone in combination, namely maltodextrin and a siloxane, respectively.

In fact, as shown in Figure 3A, the stress resistance is best for the wood board prepared with a composition comprising ground rape meal, urea, maltodextrin and a siloxane at the same time.

It is more particularly noted that:

the addition of meal and, to a lesser extent, the addition of urea substantially increase the stress resistance, while

the addition of maltodextrin or siloxane alone slightly reduces this resistance.

Now, unexpectedly, the combined addition of maltodextrin and siloxane notably increases the stress resistance.

As regards swelling in water, as shown in Figure 3B, the addition of meal notably degrades the resistance of the wood board to swelling during its immersion in water. This degradation is entirely compensated for by the addition of urea. However, the addition of maltodextrin or siloxane each causes a very slight increase in the swelling rate in water, while unexpectedly, the combined addition of maltodextrin and siloxane makes it possible to reduce this swelling rate. The best result in terms of resistance to swelling in water is thus obtained with a pressed wood board prepared with a composition comprising ground rape meal, urea, maltodextrin and a siloxane at the same time.

Example 4: Effect of the chemical nature of silicone on the properties of the pressed wood board

1. Materials

1 .1. Silicone Two polymers based on polydimethyl siloxane were tested, both supplied by Evonik (Germany):

Tegostab® B 8460: polyether - polydimethyl siloxane copolymer, and TEGO® Protect 5000: hydroxy-functionalized polydimethyl siloxane.

1 .2. Adhesive compositions

Adhesive compositions 3a and 3b utilized in this example are prepared in the same way as composition 4c of Example 2, the only difference between compositions 3a and 3b being the nature of the silicone introduced into the composition.

1 .3. Wood boards

The pressed wood boards are prepared as indicated in Example 3.

1 .4. Summary table of the wood boards obtained from adhesive compositions 3a and 3b

% by dry weight with respect to the total dry weight of the pressed wood board

Table 7: Summary table of the compositions of the wood boards obtained from adhesive compositions 3a and 3b.

2. Method

2.1 . Characterization of the compositions obtained

Adhesive compositions 3a and 3b were characterized by:

Measurement of the dry extract,

Measurement of a flow time,

Measurement of the gel time,

as described in Example 2.

2.2. Characterization of the pressed wood boards

The pressed wood boards are characterized by two parameters

Swelling in water,

Mechanical strength,

as described in Example 3.

3. Results

3.1. Results on the adhesive compositions The results of the measurements of viscosity and gel time of the compositions are presented in Table 8 below.

* Vcu: Viscous Coupling Unit

Table 8: Viscosity and gel time of adhesive compositions 3a and 3b.

3.3. Results on the pressed wood boards

The results in terms of swelling in water and mechanical strength are

Table 9 below and in Figure 4.

Table 9: Mechanical properties and water resistance of the pressed wood boards prepared using adhesive compositions 3a and 3b.

As may be noted in Figure 4A, the mechanical properties of the pressed wood boards obtained with the two surfactants are similar. In contrast, the water resistance of the pressed wood board is improved when the wood board is prepared with an adhesive composition comprising Tegostab® B 8460 with respect to a wood board that is prepared with an adhesive composition comprising TEGO® Protect 5000. However, the water resistance of the latter remains within the acceptable upper limit.

Claims

1 . Composition comprising:

- ground plants containing at least 3% by weight of proteins with respect to the total weight of ground plants,

maltodextrin, and

silicone.

2. Composition according to claim 1 , wherein the quantity of maltodextrin in the composition is comprised between 0.1 and 20% by dry weight with respect to the total dry weight of ground plants.

3. Composition according to one of claims 1 or 2, wherein the quantity of silicone in the composition is comprised between 0.5 and 30% by dry weight with respect to the total dry weight of ground plants.

4. Composition according to any one of claims 1 to 3, wherein the ground plants are one or more ground plant meal(s) chosen from the group consisting of meals of rapeseed, canola, sunflower, soya, cotton, flax, walnut, olive, mustard, hemp, oilseed poppy, maize germ, rape, safflower, kapok, maize germ, rape, shea, sesame, castorbean, camelina, jatropha, peanut, palm oil kernels, hazelnut, almond and copra.

5. Composition according to any one of claims 1 to 3, wherein the ground plants are obtained by grinding fruits and/or seeds of proteaginous plants chosen from the group consisting of pea, field bean, lupin, lentils, fenugreek and beans.

6. Composition according to any one of claims 1 to 4, wherein the ground plant meal are in the form of a powder having a median-volume diameter D₅₀ comprised between 1 and 250 μηη.

7. Composition according to any one of claims 1 to 6, in granulate form.

8. Process for the preparation of a composition according to one of claims 1 to 7 comprising the following steps:

(i) grinding the seeds and/or fruits of oleaginous and/or proteaginous plants,

(ii) the addition of maltodextrin and silicone to the ground plants obtained in step (i).

9. Preparation process according to claim 8, wherein the addition of maltodextrin and silicone performed in step (ii) is carried out by preparing at least one aqueous solution comprising maltodextrin and/or silicone.

10. Preparation process according to claim 9, wherein the aqueous solution is sprayed onto the homogenate obtained in step (i).

1 1. Preparation process according to claim 9, wherein the homogenate obtained in step (i) is placed in suspension in the aqueous solution.

12. Adhesive composition comprising a composition according to one of claims 1 to 7, and one or more precursors of a resin chosen from the group consisting of polymethylene diphenyl 4,4'-diisocyanate, urea-formaldehyde, phenol-formaldehyde and/or melamine-urea-formaldehyde.

13. Article comprising an adhesive composition according to claim 12 and a lignocellulosic material.

14. Use of a composition according to one of claims 1 to 7, for the preparation of an adhesive composition, a polyurethane foam, a cosmetic composition, a phytosanitary composition, or a food composition.