The invention relates to a composition based on acid or ester α, ω-amino-alkanoic long chain alkanoic acid or ester, and of obtaining this composition processes. This composition according the invention is usable particularly as a raw material for the production of polyamides or copolyamides.

TECHNICAL BACKGROUND

The polyamides industry uses a variety of monomers formed from diamines and dibasic acids, lactams, especially from of α, ω-amino acids. These are defined by the length of methylene chain (-CH2) n separating two amide functions -CO-NH-.

For acids or esters α, ω-aminoalkanoic, hereinafter simply "amino acids or amino esters" in the sense of the invention, in fact refers to any α, ω-amino acid long chain that is to say whose chain contains at least 8 carbon atoms.

Indeed, polyamides covered by this invention are techniques polyamides, that is to say the performance polyamides, high-performance or high performance, made from monomers having at least 8 carbon atoms, preferably at least 10 carbon atoms; as opposed to so-called polyamide "convenience" such as "nylon 6", whose amounts (volumes) traded are much higher and much lower costs than technical polyamides.

The polymerization from acid monomers or α ester, long chain ω-amino-alkanoic, to achieve high degrees of polymerization (above 80), requires monomers of high purity.

Among the most promising methods of making acid or α ester, long chain ω-amino-alkanoic include hydrogenation processes of nitriles unsaturated acids or unsaturated nitriles esters such as those described in patent applications WO08104722, WO14122412. These patent applications

describe a method for synthesizing amino acid by metathesis, hydrogenation and hydrolysis.

When polyamides manufacturing tests from such acids or esters α, ω-amino-long chain alkanoic, two problems have been highlighted. In some cases, it is not possible to obtain polyamides with a high degree of polymerization. In other cases, the melt rheology of the resulting polyamide is unstable at high temperature, of the order of 200 to 350 ° C for example, the viscosity in the molten state tends to increase. This instability can result, during the conversion of the pellets into molded or extruded parts (and in particular at a stop unexpected maker), a blockage of the injection screw or extrusion, due to too high viscosity attained. This block has several disadvantages: It is necessary to disassemble the machine and clean it before restart

There is therefore a real need to find raw material based on acid or α ester, long chain ω-amino-alkanoic that produce long-chain polyamides of high degree of polymerization, and which are stable at high temperature , that is to say, the viscosity of the melt does not increase.

The Applicant has now found an acid-based composition or α ester, long chain ω-amino-alkanoic acid, which achieves these two purposes, by combining the acid or ester α, ω-amino- alkanoic with particular content alkanoic acid or ester. It has indeed been identified by the inventors as a key component of the composition to produce long-chain polyamides having high degree of polymerization, and stable at high temperature.

DISCLOSURE OF INVENTION

Throughout the text, the pressures are expressed in bar or mbar absolute. The present invention therefore relates to a composition comprising at least one ester or acid α, ω-amino-alkanoic acid and at least one acid or alkanoic ester, characterized in that:

- the ester or acid α, ω-amino-alkanoic acid of the formula H2N- (CH2) n COOR where n = 9 to 13 and R is an alkyl group or hydrogen,

- acid or alkanoic ester has the formula R 1 -COOR 2 with R1 a linear or branched alkyl group of formula C m H 2m + 1 or C m H 2m-1 or C m H 2m-3 where m = 6 to 20 and R2 is an alkyl group or hydrogen,

- the molar ratio of acid (s) or ester (s) alkanoic and ester (s) or acid (s) α, ω-amino-alkanoic acid is in the range of 0.001 and 0.4% and preferably 0, 01 and 0.2% and more preferably between 0.02 and 0.1%.

Advantageously, n = 10 or 1 1, and R is methyl or ethyl or butyl or hydrogen.

Preferably, R1 is a linear alkyl group composition Cn-1 H2n-1 and R2 is methyl or ethyl or hydrogen.

Advantageously, the composition according to the invention further comprises at least one nitrile or acid ester nitrile of formula NC- (CH2) (n-1) -COOR, wherein the molar ratio of nitrile to acid or ester α, ω-amino-alkanoic acid is in the range from 0.0001% to 0.5%, preferably in the range from 0.0001% to 0.1%, preferably in the range from 0.0001 % to 0.05%. Advantageously, the composition according to the invention further comprises at least one secondary amine of formula ROOC- (CH 2) n -NH- (CH 2) n -COOR, wherein the molar ratio to the ester acid or α, ω -amino-alkanoic is in the range from 0.0001% to 1%, preferably from 0.0001% to 0.5%.

Advantageously, the composition according to the invention further comprises at least one dimer ROOC- (CH2) n-NH-CO- (CH2) n-NH2, the molar ratio dimer with respect to the ester or acid α, ω- amino alkanoic being in the range from 0.0001% to 5% and preferably in the range from 0.0001% to 1%.

Advantageously, the composition according to the invention further comprises at least one compound selected from: inert compounds vis-à-vis the polymerization, alcohols, water, and mixtures thereof.

Inert compounds vis-à-vis the polymerization are advantageously chosen from: aromatic hydrocarbons such as benzene, toluene, xylene, ethylbenzene; aliphatic hydrocarbons, such as cyclohexane, methylcyclohexane, pentane, heptane; or an aliphatic cutting; or an ether such as tetrahydrofuran, diethyl ether, diisopropyl ether, methyl tert-butyl; and mixtures thereof.

The alcohols are preferably selected from methanol, ethanol, butanol, and mixtures thereof.

Preferably, the possible content of inert compounds in alcohol and / or water of the present composition is less than 90%, preferably less than 50%,

preferably less than 10%, more preferably less than 2% by weight on the total weight of the composition.

Advantageously, the ester content or α acid, ω-amino-alkanoic acid is greater than 10%, preferably greater than 50%, preferably greater than 90% and more preferably greater than 98% by weight on the total weight of the composition.

The present invention also relates to a polymer, in particular polyamide, obtained by polymerization from the composition according to the invention.

The present invention also describes two possible new methods (hereafter Method A and Method B) for preparing such a composition of α ester, ω-amino-alkanoic acid and long chain alkanoic or ester whose molar ratio the alkanoic acid or ester and the α ester, long chain ω-amino-alkanoic acid is in the range of 0.001 to 0.4% from unsaturated nitrile ester. All technical challenge of these processes is to successfully reduce the acid content / alkanoic ester in the composition at a 0.4% lower content and get a good chemical yield above 70%, preferably greater than 80% and preferably greater than 90%.

PROCEDES DE PREPARATION OF COMPOSITION

method A

According to a first embodiment, the composition according to the invention is produced by a hydrogenation reaction from an unsaturated aliphatic acid nitrile or a nitrile unsaturated aliphatic ester such as:

- nitrile or unsaturated aliphatic acid ester comprises less than 0.3% or alkanoic acid ester, preferably from 0.001 to 0.3%, and preferably less than 0.1%, preferably 0.001 to 0.1 % acid / ester alkanoic;

- the hydrogenation is conducted in the presence of a heterogeneous catalyst which comprises at least Co and / or Ru;

- the hydrogenation is conducted in the presence of a base.

Preferably, the method further comprises a step of separating heavy on apparatus during residence time.

method B

According to a second embodiment, the composition according to the invention can also be produced by a sequence of two hydrogenation steps from an unsaturated aliphatic acid nitrile or a nitrile unsaturated aliphatic ester such as:

- nitrile or unsaturated aliphatic acid ester containing as impurity less than 0.3% or alkanoic acid ester, preferably from 0.001 to 0.3% and preferably less than 0.1%, preferably from 0.001 to 0, 1% acid / ester alkanoic.

- the first hydrogenation step has the function of transforming the nitrile partially or totally unsaturated aliphatic acid or unsaturated aliphatic ester nitrile or nitrile saturated aliphatic ester is conducted in the presence of a heterogeneous catalyst comprising at least palladium and / or rhodium and / or platinum.

- the second step is to form the saturated amino acid or ester and is carried out over a heterogeneous catalyst comprising at least Ni and / or Co and / or Ru

Preferably, the method further comprises a step of separating heavy on apparatus during residence time.

In both cases process, the nitrile ester / unsaturated aliphatic acid has the formula:

NC-(CH2)p-CH=CH-(CH2)q-CO2R

With p> = 0 and q> = 0 and p + q = n + 3 defined above

R defined as above.

The double bond is either cis or trans. Preferably it is a cis and trans mixture.

It can be produced by metathesis, in particular according to the methods described in: WO2008 / 104722, WO10 / 089512, WO13 / 017782, WO13 / 017786, WO13 / 030481, WO14 / 106766, WO14 / 106723, WO14 / 106724, WO14 / 147337.

Preferably, a crude mixture from the metathesis reaction is subjected to purification steps. These purifications are for example steps to remove or inactivate the metathesis catalyst, distillation steps to remove the solvent and / or reagents or impurities light and / or heavy impurities. The reagents are removed for example esters or acids or nitriles. The heavy impurities removed may be, for example fatty acids or esters such as methyl oleate or diesters such as compound RO2C- (CH2) q-CH = CH- (CH2) q-CO2R.

The (thus obtained mixture based) unsaturated aliphatic nitrile ester or nitrile unsaturated aliphatic acid used contains less than 0.3% acid or alkanoic ester and preferably less than 0.1%.

Preferably, the unsaturated aliphatic nitrile ester or nitrile unsaturated aliphatic acid contains less than 1% and preferably less than 0.1% diester.

Specific features to process A:

The hydrogenation is carried out in the presence of at least one heterogeneous hydrogenation catalyst which contains cobalt and / or ruthenium.

The catalyst of the invention typically contains 0.1 to 10% of ruthenium, and preferably 1 to 5%, and / or 1% to 90% cobalt, preferably 5% to 60%.

Cobalt and / or ruthenium is preferably in its reduced metallic form. The catalyst introduced into the reactor according to the invention may nevertheless contain oxides of ruthenium or cobalt such as a passivation layer.

In addition to the cobalt or ruthenium, the catalyst may contain other metals, such as iron, nickel, chromium, manganese, rhodium, osmium, iridium, platinum, or palladium. The catalyst may also be doped with alkali metal such as sodium, potassium, rubidium or cesium or alkaline earth metal such as magnesium, calcium, strontium or barium.

The catalyst may be in finely divided form, for example in the form of a Raney catalyst. It may also be in the form of granules, or may be deposited on a support. Examples of suitable carriers are pumice, titanium dioxide, carbon, charcoal, silicon carbide (preferably form beta SiC), alumina, silica, a mixture of silica and alumina, soapstone.

The catalyst in pellet form or supported on a carrier may be in any form such as: sphere, grain, hollow cylinder, trefoil and quatrefoil, as well as in the form of cylinders, extrudates or compressed possibly using a tableting agent .

The preparation of finely divided Raney catalyst is widely known in the prior art.

The catalysts can be prepared with the known methods for loading the metal on a support. For example, a catalyst can be prepared by contacting the support with an aqueous or alcoholic solution of ruthenium trichloride, ruthenium nitrosyl nitrate, or soluble ruthenium salt in water or an alcohol, cobalt carbonate, nitrate cobalt or cobalt salt soluble in water or alcohol, and then evaporating the water or alcohol and activating the catalyst by means of heating and reduction in a gas stream containing hydrogen. The cobalt-containing catalysts will typically be calcined at temperatures of 300 to 500 ° C and reduced at from 300 to 500 ° C.

Other metals such as iron, nickel, chromium, manganese, rhodium, osmium, iridium, platinum, or palladium, and the alkali or alkaline earth metal can be introduced on the catalyst the same way as ruthenium or cobalt, or prior to the contacting of the ruthenium salt solution or cobalt with the support, either concomitantly or at a later stage.

The catalysts may also be prepared by known techniques of precipitation or coprecipitation followed by steps of calcination and reduction in a gas stream containing hydrogen. The precipitation steps are used to obtain a solid containing cobalt primarily as CoO, Co3O4 and / or CoO (OH), optionally doped with iron, nickel, chromium, manganese, rhodium, osmium, iridium, platinum, or palladium or alkali or alkaline earth or silica or alumina or a mixture of silica and alumina. The solid may be calcined at a typical temperature of 300 to 500 ° C and is reduced in a gaseous stream containing hydrogen at temperatures from 300 to 500 ° C. The catalysts used are sensitive to air or even pyrophoric. They may undergo passivation step so you can load the hydrogenation reactors safely. There are numerous passivation techniques. For example, they can be passivated depleted air or in air at a temperature near room temperature, or with sulfur compounds. They may be encapsulated in paraffin or saturated esters which will melt at the start of the reactor and remove in the reaction medium. They can also be packaged and handled in the presence of water or an organic solvent. air at a temperature near room temperature, or with sulfur compounds. They may be encapsulated in paraffin or saturated esters which will melt at the start of the reactor and remove in the reaction medium. They can also be packaged and handled in the presence of water or an organic solvent. air at a temperature near room temperature, or with sulfur compounds. They may be encapsulated in paraffin or saturated esters which will melt at the start of the reactor and remove in the reaction medium. They can also be packaged and handled in the presence of water or an organic solvent.

Advantageously, the hydrogenation reaction is conducted at a pressure in the range from 5 to 100 bar, preferably from 20 to 80 bar.

Advantageously, the temperature is in the range of 50 to 150 ° C, preferably from about 80-1 10 ° C.

a base is added to decrease the selectivity of secondary amine. The base may typically be sodium hydroxide, sodium methoxide, potassium hydroxide, potassium tert-butoxide, or ammonia, and mixtures thereof. Preferably, use is made of ammonia. The molar ratio base / unsaturated nitrile ester is typically in the range of 0.1 to 4 and preferably 0.3 to 2.5.

In one embodiment, hydrogenation is carried out in the absence of solvent. According to a preferred embodiment, the hydrogenation is conducted in the presence of a solvent. The solvent may be an aromatic hydrocarbon such as benzene, toluene, xylene, ethylbenzene, or an aliphatic hydrocarbon such as cyclohexane, pentane, heptane, methylcyclohexane or an aliphatic cutting, or an alcohol, such as methanol, ethanol, propanol or isopropanol, butanol or an isomer, or an ester such as ethyl or methyl acetate, or an ether such as tetrahydrofuran, diethyl ether, diisopropyl ether, methyl tert-butyl or an amide such as dimethylformamide, N-methyl pyrrolidone or a carbonate such as dimethylcarbonate, diethylcarbonate, ethylene carbonate, propylene carbonate; or a mixture of these solvents.

Preferably the solvent comprises toluene, xylene, cyclohexane or methylcyclohexane, or mixtures thereof.

The concentration of nitrile ester / unsaturated acid in the solvent may vary from 1 to 70% and preferably from 10 to 50% by mass.

The amount of hydrogen used is preferably in the range from 3 to 200 moles per 1 mole of nitrile ester / unsaturated acid. The hydrogen partial pressure h is at least 5 bar and at most 100 bars and preferably at least 15 bar and at most 80 bar.

Reactor type:

The nitrile ester / unsaturated acid optionally mixed with a solvent and / or base form a liquid phase which is contacted with the solid catalyst in any suitable manner and is fed hydrogen gas in contact with the solid catalyst and liquid phase.

In the case where a finely divided catalyst is used, it may be dispersed in the liquid phase, and maintained dispersed by stirring. This stirring can be performed in a reactor equipped with a stirrer, preferably an auto-suction turbine, by a recirculation liquid provided with a gas ejector (jet loop, Buss loop). [Http://www.airproducts.com/~/media/downloads/h/hydrogen-support-microsite/hydrogen-support-increasing-productivity-in-slurry-hydrogenation-process.pdf description]. In this case, the size of the catalyst particles is preferably less than one millimeter typically in the range of 1 to 100 μιτι. One can also use a type of reactor Continuous Oscillatory Baffled Reactor.

An easy way of implementing the hydrogenation is to use a bed of pellets or solid catalyst granules. Can be passed the liquid phase on the catalyst, for flow in the same direction or against the flow of a stream of hydrogen. The catalyst bed can be completely immersed in the solution, or the bed can be used as a trickle bed. In this case the size of the catalyst particles is in the range of 1 to 10 mm and preferably in the range of 1 to 5 mm. One can also use a catalyst in the form of a structured monolith (e.g. in the form of a ceramic foam as a SiC foam for supporting the active phase).

The reaction may be carried out discontinuously in batches (batch) or continuous.

When loading a new batch of catalyst in a reactor, the latter may undergo conditioning before being contacted with the unsaturated nitrile ester. This conditioning may be made in steps of inerting, thermal treatment and / or injection of hydrogen in increasing concentration.

The heat generated by the reaction can be removed by any means known to those skilled in the art: by heat exchangers situated inside the reactor or located in an external recirculation loop to the reactor or by circulating a cooling fluid in the case of jacketed reactor or a tube reactor or plate reactor; or by the multi-staged injection of reactant cold as cold hydrogen.

The quantities of catalyst to be used vary depending on the catalyst activity and the reaction conditions especially temperature and pressure. In batchwise operation, the mass ratio of catalyst relative to the mass of unsaturated nitrile ester can vary from 0.01 to 1 and preferably from 0.05 to 0.3. The reaction time is in the range from 1 h to 24 h and preferably in the range from 3h to 15h. In continuous operations, the liquid space velocity of the catalyst, expressed in kg / h of unsaturated nitrile ester divided by kg of catalyst may vary from 0.01 to 10 h -1, preferably 0.05 to 2 h-1 .

This is the choice of catalyst described above which limits the production of esters / alkanoic acid relative to the amount of ester or acid α, ω-amino-alkanoic acid in the hydrogenation step.

By hydrogenating using the method described nitrile ester / unsaturated acid containing less than 0.3% acid or alkanoic ester there is obtained a composition containing a molar ratio of alkanoic acids or esters and the ester or acid α, ω- amino alkanoic in the range of 0.001 to 0.4%.

Under these conditions, the skilled artisan knows how to adapt the reaction conditions of hydrogenation (amount of catalyst, pressure, temperature) so as to maximize the conversion of the nitrile ester / unsaturated acid and to obtain a nitrile content ester / unsaturated acid which is formed intermediately in the range from 0.0001% to 0.5% and preferably from 0.0001% to 0.1 mol% relative to the ester or acid α, ω-amino-alkanoic.

specific characteristics to the process B

The first hydrogenation step is carried out over a heterogeneous catalyst containing at least palladium or rhodium or platinum, or mixtures thereof, preferably at least palladium.

The catalyst of the invention typically contains from 0.1 to 10% palladium or rhodium and / or platinum, and preferably from 0.2 to 5%.

Palladium or rhodium or platinum is preferably carried on a support. Examples of suitable carriers are pumice, titanium dioxide, carbon, charcoal, silicon carbide (preferably form beta SiC), alumina, silica, a mixture of silica and alumina, talc or calcium carbonate.

The catalyst may be in any form such as: powder, sphere, grain, hollow cylinder, trefoil and quatrefoil, as well as in the form of cylinders, extrudates or compressed possibly using a tableting agent.

Advantageously, the first hydrogenation reaction is conducted at a pressure in the range from 1 to 90 bar, preferably from 1 to 50 bar, preferably from 2 to 20 bar, preferably from 2 to 10 bar.

Advantageously, the temperature is in the range of 10 to 100 ° C, preferably from 20 to 100 ° C, preferably in the range of 20 to 50 ° C, preferably from 30 to 50 ° C.

This step is generally carried out without solvent.

According to another embodiment, the hydrogenation is conducted in the presence of a solvent. The solvent may be an aromatic hydrocarbon such as benzene, toluene, xylene, ethylbenzene; or an aliphatic hydrocarbon such as cyclohexane, pentane, heptane, methylcyclohexane; or an aliphatic cutting; or an alcohol such as methanol, ethanol, propanol or isopropanol, butanol or an isomer, or an ester such as ethyl or methyl acetate; or an ether such as tetrahydrofuran, diethyl ether, diisopropyl ether, methyl tert-butyl; or an amide such as dimethylformamide, N-methyl pyrrolidone; or a carbonate such as dimethylcarbonate, diethylcarbonate, ethylene carbonate, propylene carbonate; and mixtures thereof.

Preferably the solvent is selected from toluene, xylene, cyclohexane or methylcyclohexane, or mixtures thereof.

The concentration of unsaturated nitrile ester in the solvent may vary from 1 to 70%, preferably from 10 to 50% by mass.

The reaction may be carried out discontinuously in batches or continuously. The quantities of catalyst to be used vary depending on the catalyst activity and the reaction conditions especially temperature and pressure. In batchwise operation, the mass ratio of catalyst relative to the mass of unsaturated nitrile ester can vary from 0.01 to 1 and preferably from 0.05 to 0.3. The reaction time is in the range of 30 minutes to 24 hours and

preferably from 1 h to 10h. In continuous operations, the liquid space velocity of the catalyst, expressed in kg / h of nitrile ester / acid divided per kg of catalyst may vary from 0.01 to 10 h -1 , preferably from 0.05 to 6 h -1 , preferably from 0.05 to 4 h -1 , preferably 0.05 to 2 h -1 , preferably from 0.2 to 2 h -1 , preferably 0.5 to 2 h "1. Be adapted under these conditions: the amounts of catalyst used, the temperature, pressure and reaction time or the space velocity so as to convert more than 70% of the unsaturated ester nitrile and preferably more than 90% and more preferably more than 95% the product formed is predominantly the nitrile ester / unsaturated acid of the formula NC- (CH2) (p + q + 2) -CO 2 R, with a conversion rate in the range from 70% to 99.5%, preferably in the range of 80 to 99%, preferably in the range of 90 to 99%, preferably in the range of 95 to 99%.

Advantageously, the reaction in the first hydrogenation is carried out in the absence of base.

The reaction medium resulting from the first hydrogenation is subjected to a second hydrogenation which is performed in the presence of a heterogeneous catalyst which contains nickel and / or cobalt and / or ruthenium.

The catalyst of the invention typically contains 1% to 90% nickel, preferably 5% to 60%, and / or 1% to 90% cobalt, preferably 5% to 60% and / or 0.1 to 10% of ruthenium, and preferably 1 to 5%. Nickel and / or cobalt and / or ruthenium is preferably in its reduced metallic form. The catalyst introduced into the reactor according to the invention may nevertheless contain nickel oxides, cobalt or ruthenium such as a passivation layer. In addition to the nickel or cobalt or ruthenium, the catalyst may contain other metals, such as iron, nickel, chromium, manganese, rhodium, osmium, iridium, platinum, or palladium. The catalyst may also be doped with alkali metal such as sodium, potassium, rubidium or cesium or alkaline earth metal such as magnesium, calcium, strontium or barium. The catalyst may be in finely divided form, for example in the form of a Raney catalyst. It may also be in the form of granules, or may be deposited on a support. Examples of suitable carriers are pumice, titanium dioxide, carbon, charcoal, silicon carbide (preferably form beta SiC), alumina, silica, a mixture of silica and alumina, soapstone.

The catalyst in pellet form or supported on a carrier may be in any form such as: sphere, grain, hollow cylinder, trefoil and quatrefoil, as well as in the form of cylinders, extrudates or compressed possibly using a tableting agent .

Advantageously, the second hydrogenation reaction is conducted at a pressure in the range from 5 to 100 bar, preferably from 20 to 80 bar.

Advantageously, the temperature is in the range of 50 to 150 ° C, preferably from about 80-1 10 ° C.

a base is added to decrease the selectivity of secondary amine. The base may typically be sodium hydroxide, sodium methoxide, potassium hydroxide, potassium tert-butoxide, or ammonia. Preferably used ammonia. The amount of base used in the second hydrogenation reaction is such that the molar ratio base / ester nitrile or unsaturated acid to the input of the first hydrogenation is typically in the range of 0.1 to 4 and preferably in the range of 0.3 to 2.5.

IF the first hydrogenation took place in the absence of solvent, the second hydrogenation can also be achieved in the absence of solvent. It can also be performed in the presence of a solvent. The solvent may be an aromatic hydrocarbon such as benzene, toluene, xylene, ethylbenzene; or an aliphatic hydrocarbon such as cyclohexane, pentane, heptane, methylcyclohexane or an aliphatic cutting; or an alcohol such as methanol, ethanol, propanol or isopropanol, butanol or an isomer; or an ester such as ethyl or methyl acetate; or an ether such as tetrahydrofuran, diethyl ether, diisopropyl ether, methyl tert-butyl; or an amide such as dimethylformamide, N-methyl pyrrolidone; or a carbonate such as dimethylcarbonate, diethylcarbonate, carbonate of ethylene, propylene carbonate; and mixtures thereof.

Preferably the solvent is selected from toluene, xylene, cyclohexane or methylcyclohexane, or mixtures thereof.

The concentration of nitrile ester or acid (unsaturated and saturated) in the solvent can vary from 1 to 70% and preferably from 10 to 50% by mass.

The amounts of catalyst used in the second hydrogenation may vary depending on the catalyst activity and the reaction conditions especially temperature and pressure. In batchwise operation, the mass ratio of catalyst relative to the mass of ester nitrile or acid (saturated and unsaturated) may vary from 0.01 to 1 and preferably from 0.05 to 0.3. The reaction time is in the range from 1 h to 24 h, preferably 3 h at 15h. In continuous operations, the liquid space velocity of the catalyst, expressed in kg / h of nitrile ester divided by kg of catalyst may vary from 0.01 to 10 hr "1 , preferably 0.05 to 2 h -1 .

Those skilled in the art can adapt the reaction conditions of the second hydrogenation, preferably in the above ranges (amount of catalyst, temperature, pressure) so as to maximize the conversion of the nitrile and saturated ester to obtain a nitrile content saturated ester in the range of 0.0001% to 0.5% and preferably from 0.0001% to 0.1 mol% relative to the ester or acid α, ω-amino-alkanoic.

Features common to process A and B

Advantageously, is subjected to the reaction mixture from the hydrogenation step at least one of the following purification steps:

separation of the catalyst by any means of solid-liquid separation known to those skilled in the art,

separation of the base: in the case of ammonia by evaporation or aqueous wash, and in the case of other bases by aqueous washing or tailing in a device during residence time.

optional separation of the solvent by evaporation or topping.

- separation of heavy and, in particular of the secondary amine formed in the hydrogenation, by tailing in a vacuum residence time during apparatus at a controlled temperature.

Devices to short residence time of the invention are film evaporators, such as falling film evaporators or thin layer evaporators where the liquid film is created mechanically or by centrifugal force. The evaporator typical thin layer consists of a tubular heat exchange surface equipped with an external heating jacket and internally provided with a bladed rotor, with fixed or movable scrapers. The blades and scrapers serve to spread the liquid in the form of a thin film, in order to promote heat exchange and evaporation of the product, while limiting its residence time and reducing training and deposits fouling oligomers and polymers.

The vapors can be condensed in an external or internal condenser. Advantageously, the vapors may be condensed in a condenser inside the evaporator so as to work under vacuum yet further less than 5 or 1 mbar. We speak of thin film evaporator short trip. Preferably, the separation of heavy is performed in a thin film evaporator, preferably a thin layer evaporator short path, the heavy separation step is preferably carried out at a temperature below 160 ° C, preferably less than 140 ° C, preferably below 130 ° C.

The skilled person knows will adjust the pressure according to the vapor pressure curve of the ester or acid α, ω-amino-alkanoic saturated, so as to vaporize the ester or acid into the apparatus at short residence times and recovering in the distillation residues of the heavy products and in particular of the secondary amine formed in the hydrogenation. Due to the low volatility of esters α, ω-amino-alkanoic saturated with the invention, it is necessary to work at high vacuum, usually less than 20 mbar, preferably at a pressure in the range of 0.5 to 20 mbar, preferably 1 to 20 mbar, preferably lower than 10 mbar, preferably at a pressure of 0.5 to 5 mbar, preferably 1 to -5 mbar.

The step of separation of heavy provides a composition which comprises a molar ratio between the secondary amine of formula ROOC- (CH2) n-NH- (CH2) n-COOR, and the ester or acid α, ω- amino alkanoic in the range from 0.0001% to 1% and preferably from 0.0001% to 0.5), and an initial molar ratio between the dimer ROOC- (CH2) n-NH-CO- (CH2) n-NH2 and the ester or acid α, ω-amino-alkanoic acid in the range of 0.0001% to 1%.

USE OF THE COMPOSITION

The composition according to the invention is usable as a raw material for the manufacture of long chain polyamide.

In the case of a composition containing α ester, ω-amino-alkanoic acid, the manufacture of polyamide may in particular be carried out in two steps as described for example in patent document WO2015 / 071604, a first reaction step presence of water at a first temperature, having for

according to at least partially hydrolyze the ester function, and a second reaction step at a higher temperature for obtaining the desired degree of polymerization.

The composition according to the invention allows to obtain a polyamide with a degree of polymerization greater than 80, the degree of polymerization of a polyamide is measured by proton NMR, as twice the molar ratio of amide functions on the one hand and the sum of the chain ends (such as amino, acid, and alkyl ester) on the other.

The composition according to the invention also allows to obtain a polyamide whose rheology melt increases more weakly at high temperature, as can be measured for example by following the evolution of the viscosity in the molten state rheometry plane-plane for 30 minutes at 270 ° C. Determining the viscosity in the molten state at T0, and then after 30 minutes and the percentage of variation between the two. A lower final viscosity for example less than 60,000 and preferably less than 45000 Pa · s makes it possible to avoid the risk of locking screws of the processing machine if the queue due to an unexpected stop of the production.

Ultimately, the solution of the present invention has several important advantages over the prior art:

The composition allows the production of long-chain polyamides having high degree of polymerization, and which are stable at high temperature.

With respect to the hydrogenation processes of the prior art, the disclosed methods allow a controlled manner to limit the amount of acid or alkanoic esters relative to the amino acid / ester, which allows the end of manufacture polymers more easily. They also allow to obtain the composition according to the invention with high efficiency.

EXAMPLES

Example 1 Preparation of a composition according to the invention

Unsaturated nitrile methyl ester of 10-cyano-9-decenoate (NEI1 1) is prepared by reaction of methyl 9-decenoate with acrylonitrile according to Example 5 of WO2014 / 122410 followed by evaporation of the toluene and reduced pressure distillation so as to obtain the NEI1 1 containing less than 100 molar ppm of methyl decenoate.

In a 1 liter autoclave provided with an auto-suction turbine are introduced 13.5 g of Raney cobalt washed with methanol (ActiCatTM3100 the Catalloy company) and 90 g of unsaturated nitrile ester NEI1 1 and 210 g of toluene. The autoclave was purged with nitrogen and then introduced 4.3 g of ammonia (0.253 mol) and hydrogen was added so as to bring the pressure to 60 bar. at 90 ° C is heated and allowed to react 10 hours under vigorous stirring while maintaining the pressure at 60 bars by addition of hydrogen.

The reactor was then cooled to room temperature, the pressure is lowered to atmospheric pressure. The solid is separated from the liquid phase and washed with toluene. The combined liquid phases are evaporated in a rotary evaporator at 30 ° C at a pressure which is gradually reduced to 1 mbar. The residual liquid phase was analyzed by gas chromatography: it contains 96% of primary amine, secondary amine 2.4%, 0.1% methyl decanoate, 0.1% saturated nitrile ester 10-cyano-decanoate methyl (NE1 1) and 1% toluene (% by weight).

This residual liquid phase is then distilled continuously in a scraped film evaporator short KDL4 type path (UIC). The evaporator is maintained at a pressure of 0.7 mbar. The liquid to be distilled is fed at 150 g / h through the top of the evaporator and forms a film on the heat exchange surface heated to 120 ° C with roller scrapers. The vapors are condensed on a central exchanger maintained at 15 ° C.

Recovering a composition of 1 1 methyl -aminoundécanoate (AE1 1) and methyl decanoate (DM) in a molar ratio 99.9 / 0.1. The mass content AE1 1 in the composition was 98.9%, the saturated nitrile methyl ester of 10-cyano-decanoate (NE1 1) 0.1%, the secondary amine

formula (MeCO2 (CH2) io) 2NH 0.01% and 0.5% in toluene. The molar yield of 1 AE1 of reaction steps and separation is 86%.

Example 2: Polymerization of the composition obtained in Example 1

The composition of one and AE1 DM of Example 1 (100 g), water (100g) and 85% phosphoric acid (0.06 g) are introduced into a total reflux reactor. The reaction mixture to 1 10 ° C for 90 minutes with vigorous stirring. The medium is then lyophilized (so as to remove water and methanol) and the lyophilisate was heated to 250 ° C under nitrogen in a glass reactor previously rendered inert with nitrogen. 0:30 after heating, the resulting polymer was cooled and analyzed by proton NMR. The degree of polymerization is calculated from NMR analysis: This is twice the molar ratio of amide functions on the one hand and the sum of the chain ends (such as amino, acid, and alkyl ester) of 'somewhere else.

The stability of the rheology in the molten state is measured by following the change in viscosity melt rheometry in plate-plate for 30 minutes at 270 ° C. Determining the viscosity in the molten state at T0, and then after 30 minutes and the percentage of variation between the two.

The results are reported in Table 1.

Comparative Example 3:

Example 1 is repeated with a Raney nickel catalyst (WR Grace and Co. Raney 2800 grading over 89% Ni). The results are reported in Table 1.

The residual liquid phase after evaporation of toluene containing 95.5% of primary amine, secondary amine 2.4%, 0.6% methyl decanoate, 0.1% saturated nitrile ester NE1 1 and 1% toluene (% by weight).

After distillation, recovering a composition AE1 DM 1 and in a molar ratio 99.4 / 0.6. The mass content AE1 1 in the composition was 98.4%, the saturated nitrile methyl ester of 10-cyano-decanoate (NE1 1) 0.1%, the secondary amine of formula (MeCO2 (CH2) io ) 2NH 0.02% and the 0.5% toluene.

Example 4: Polymerization of the composition obtained in Example 3

The composition of one and AE1 DM of Example 3 was polymerized in the same manner as in Example 2 and measuring the degree of polymerization and stability of the rheology in the molten state. The results are reported in Table 1.

It is found that the degree of polymerization is much lower as in Example 2.

claims

1 - Composition comprising at least one ester or acid α, ω-amino-alkanoic acid and at least one acid or alkanoic ester, characterized in that:

- the ester or acid α, ω-amino-alkanoic acid of the formula HN Ch COOR where n = 9 to 13 and R is an alkyl group or hydrogen,

- acid or alkanoic ester has the formula R 1 COOR 2 with R a linear or branched alkyl group of formula m + i MHC or MHC I or C m H2m-3 where ιτι = 6 to 20 and R2 is an alkyl group or a hydrogen,

- the molar ratio of acid (s) or ester (s) alkanoic and ester (s) or acid (s) α, ω-amino-alkanoic acid is in the range of 0.001 to 0.4%.

2- The composition of claim 1 wherein n = 10 or 1 1, and R is methyl or ethyl or butyl or hydrogen.

3- A composition according to any one of claims 1 or 2, wherein Ri is a linear alkyl group of composition C n -i H2n-i and R2 is methyl or ethyl or hydrogen.

4- A composition according to any one of claims 1 to 3, wherein the molar ratio of acid (s) or ester (s) alkanoic and ester (s) or acid (s) α, ω-amino-alkanoic is included in the range of 0.01 to 0.2%, preferably in the range of 0.02 to 0.1%.

5- A composition according to any one of claims 1 to 4, characterized in that it further comprises a nitrile or a nitrile acid ester of the formula NC- (CH 2) (ni) -COOR, wherein the molar ratio of nitrile with respect to the ester or acid α, ω-amino-alkanoic acid is in the range from 0.0001% to 0.5%, preferably in the range from 0.0001% to 0.1%, preferably in the range from 0.0001% to 0.05%.

6- A composition according to any one of claims 1 to 5, characterized in that it further comprises a secondary amine of formula ROOC- (CH 2) n -NH- (CH2) n-COOR, wherein the molar ratio by based on the ester or acid α, ω-amino-alkanoic acid is in the range from 0.0001% to 1%, preferably from 0.0001% to 0.5%.

7- A composition according to any one of claims 1 to 6, characterized in that it further comprises dimer ROOC- (CH2) n -NH-CO- (CH2) n - Nh, the molar ratio relative dimer to the ester or acid α, ω-amino-alkanoic acid being in the range from 0.0001% to 5% and preferably in the range from 0.0001% to 1%.

8- A composition according to any one of claims 1 to 7, characterized in that it further comprises at least one compound selected from: inert compounds vis-à-vis the polymerization, alcohols, water, and mixtures thereof.

9- A composition according to claim 8, characterized in that the inert vis-à-vis the polymerization compounds are selected from: aromatic hydrocarbons such as benzene, toluene, xylene, ethylbenzene; aliphatic hydrocarbons, such as cyclohexane, methylcyclohexane, pentane, heptane; an aliphatic-section; an ether such as tetrahydrofuran, diethyl ether, diisopropyl ether, methyl tert-butyl; and mixtures thereof.

10- A composition according to any one of claims 8 or 9, characterized in that the alcohols are selected from methanol, ethanol, butanol, and mixtures thereof.

1 1 - Composition according to any one of claims 8 to 10, characterized in that the content of inert compounds in alcohol and / or water, is less than 90%, preferably less than 50%, preferably less than 10%, more preferably less than 2% by weight on the total weight of the composition.

12- A composition according to any one of claims 1-1 1, characterized in that the content of ester or acid α, ω-amino-alkanoic acid is greater than 10%, preferably greater than 50%, preferably greater than 90 % and more preferably greater than 98% by weight on the total weight of the composition.

13- polymer including polyamide, obtained by polymerizing the composition of any one of claims 1 to 12, characterized in that its degree of polymerization is greater than 80.

14- A method for preparing the composition according to any one of claims 1 to 12 comprising hydrogenating a nitrile acid / unsaturated aliphatic ester in the presence of hydrogen, characterized in that:

- nitrile acid / unsaturated aliphatic ester further contains 0.001 to 0.3%, preferably 0.001 to 0.1%, acid / ester alkanoic; and

- the hydrogenation is carried out in the presence:

i. a heterogeneous catalyst which comprises from 1 to 90%, preferably from 5 to 60% of Co and / or 0.1 to 10%, preferably 1 to 5% Ru; and

ii. of a base, the molar ratio base / nitrile is in the range from 0.1 to 4, preferably in the range of 0.3 to 2.5.

15. The method of claim 14, wherein the reaction is carried out continuously.

16- The method of claim 15, wherein the liquid space velocity of the catalyst, expressed in kg / h divided nitrile ester per kg of catalyst is in the range 0.01 to 10 h -1 , preferably from 0.05 to 2 h -1 .

17- A method according to any one of claims 14, wherein the reaction is carried out batchwise batchwise.

18- The method of claim 17, wherein the weight ratio of catalyst relative to the mass of nitrile acid / unsaturated ester is in the range of 0.01 to 1, preferably 0.05 to 0.3, and the reaction time is in the range from 1 h to 24 h, preferably in the range from 3h to 15h.

19- A method according to any one of claims 14 to 18, wherein the hydrogenation is conducted at a pressure in the range of 5 to 100 bar, preferably from 20 to 80 bar and at a temperature in the range from 50 to 150 ° C, preferably from about 80-1 10 ° C. 20- A method according to any one of claims 14 to 19, wherein the base is selected from: sodium hydroxide, sodium methoxide, potassium hydroxide, potassium tert-butoxide, ammonia, and mixtures thereof; preferably the base is ammonia.

21 - Process according to any one of claims 14 to 20, wherein the hydrogenation is carried out without solvent.

22- A method according to any one of claims 14 to 20, wherein the hydrogenation is carried out in the presence of a solvent selected from: aromatic hydrocarbons such as benzene, toluene, xylene, ethylbenzene; aliphatic hydrocarbons such as cyclohexane, pentane, heptane, methylcyclohexane, or an aliphatic-section; alcohols, such as methanol, ethanol, propanol, isopropanol, butanol and isomers thereof; esters, such as ethyl or methyl acetate; ethers such as tetrahydrofuran, diethyl ether, diisopropyl ether, methyl tert-butyl; amides, such as dimethylformamide, N-methyl pyrrolidone; carbonates, such as dimethylcarbonate, diethylcarbonate, ethylene carbonate, propylene carbonate; and mixtures thereof; preferably the

23- The method of claim 22, wherein the nitrile concentration acid / unsaturated ester in the solvent is in the range of 1 to 70% by mass, preferably in the range of 10 to 50% by mass.

24- A method according to any one of claims 14 to 23, wherein the amount of hydrogen used is in the range from 3 to 200 moles per 1 mole of nitrile acid / unsaturated ester, the hydrogen partial pressure being in the range of 5 bar to 100 bar, preferably in the range 15 bars to 80 bars.

25- A method according to any one of claims 14 to 24, characterized in that it further comprises a step of separating heavy device on the short residence time.

26-Method B for the preparation of the composition according to any one of claims 1 to 12, comprising two successive steps of hydrogenation from a nitrile acid / unsaturated aliphatic ester, characterized in that: - the nitrile acid / ester aliphatic unsaturated contains as impurity of 0.001 to 0.3%, preferably 0.001 to 0.1%, acid / ester alkanoic; and

- the first hydrogenation step is carried out in the presence of a heterogeneous catalyst comprising from 0.1 to 10%, preferably from 0.2 to 5%, of palladium and / or rhodium and / or platinum, preferably palladium, so that the nitrile acid / unsaturated aliphatic ester is converted to the nitrile acid / saturated aliphatic ester of the formula NC- (CH 2) ( P + q 2) -CO 2 according to a conversion rate in the range of 70% to 99.5%, preferably in the range of 80 to 99%, preferably in the range of 90 to 99%, preferably in the range of 95 to 99%; and

- the second hydrogenation step is performed in the presence of a heterogeneous catalyst which comprises from 1% to 90%, preferably from 5 to 60% Ni and / or from 1 to 90%, preferably from 5 to 60% Co and / or 0.1 to 10%, preferably 1 to 5% of Ru, so that the nitrile acid / saturated aliphatic ester is transformed into amino acid ester / saturated.

27. The method of claim 26, wherein the first hydrogenation step is conducted at a pressure in the range from 1 to 90 bar, preferably from 1 to 50 bar, preferably from 2 to 20 bar, preferably of 2 to 10 bar and at a temperature in the range of 10 to 100 ° C, preferably from 20 to 100 ° C, preferably from 20 to 50 ° C, preferably from 30 to 50 ° C.

28- A method according to any one of claims 26 or 27, wherein the first hydrogenation step is carried out without solvent.

29- A method according to any one of claims 26 or 27, wherein the first hydrogenation step is carried out in the presence of a solvent selected from: aromatic hydrocarbons such as benzene, toluene, xylene, ethylbenzene; aliphatic hydrocarbons such as cyclohexane, pentane, heptane, methylcyclohexane, or an aliphatic-section; alcohols, such as methanol, ethanol, propanol, isopropanol, butanol and isomers thereof; esters, such as ethyl or methyl acetate; ethers such as tetrahydrofuran, diethyl ether, diisopropyl ether, methyl tert-butyl; amides, such as dimethylformamide, N-methyl pyrrolidone; carbonates, such as dimethylcarbonate,

diethylcarbonate, ethylene carbonate, propylene carbonate; and mixtures thereof; preferably the first hydrogenation step is carried out in the presence of a solvent selected from: toluene, xylene, cyclohexane, and mixtures thereof.

30- A method according to any one of claims 26 to 29, wherein the nitrile concentration acid / unsaturated ester in the solvent is in the range of 1 to 70% by mass, preferably in the range of 10 to 50% by mass .

31 - Process according to any one of claims 26 to 30, wherein the reaction in the first hydrogenation is carried out continuously.

32- The method of claim 31, wherein the liquid space velocity of the catalyst, expressed in kg / h of acid nitrile / ester divided kg

catalyst is in the range 0.01 to 10 h -1 , preferably from 0.05 to 6 h -1 , preferably 0.05 to 2 h -1 , preferably 0.2 to 2 hours - 1 .

33- A method according to any one of claims 26 to 32, wherein the reaction in the first hydrogenation is carried out batchwise batchwise.

34. The method of claim 33, wherein the weight ratio of catalyst relative to the mass of nitrile acid / unsaturated ester is in the range of 0.01 to 1, preferably 0.05 to 0.3, and the reaction time is in the range of 30 minutes to 24 hours, preferably in the range of 1 h to 10h.

35. A method according to any one of claims 26 to 34, wherein the reaction in the first hydrogenation is carried out in the absence of base.

36- Method according to one of claims 26 to 35, wherein the second hydrogenation reaction is conducted at a pressure in the range of 5 to 100 bar, preferably 20 to 80 bars; and at a temperature in the range of 50 to 150 ° C, preferably from about 80-1 10 ° C.

37- A method according to any one of claims 26 to 36, wherein the second hydrogenation is carried out in the presence of a base, amount

such that the molar ratio base / unsaturated nitrile ester at the entrance to the first hydrogenation is in the range from 0.1 to 4, preferably 0.3 to 2.5; said base being preferably selected from sodium hydroxide, sodium methoxide, potassium hydroxide, potassium tert-butoxide, or ammonia, preferably ammonia.

38- A method according to any one of claims 26 to 37, wherein the second hydrogenation is carried out in the absence of solvent, in particular if the first hydrogenation took place in the absence of solvent.

39- A method according to any one of claims 26 to 37, wherein the second hydrogenation is carried out in the presence of a solvent selected from: aromatic hydrocarbons, such as benzene, toluene, xylene, ethylbenzene; aliphatic hydrocarbons, such as cyclohexane, pentane, heptane, methylcyclohexane; an aliphatic-section; alcohols, such as methanol, ethanol, propanol or isopropanol, butanol and isomers thereof; esters, such as ethyl or methyl acetate; ethers such as tetrahydrofuran, diethyl ether, diisopropyl ether, methyl tert-butyl; amides, such as dimethylformamide, N-methyl pyrrolidone; carbonates, such as dimethylcarbonate, diethylcarbonate, ethylene carbonate, propylene carbonate; and mixtures thereof;

40- The method of claim 39, wherein the nitrile concentration acid / unsaturated ester in the solvent is in the range of 1 to 70% by mass, preferably in the range of 10 to 50% by mass.

41 - Process according to any one of claims 26 to 40, wherein the second hydrogenation is carried out continuously.

42. The method of claim 41, wherein the liquid space velocity of the catalyst, expressed in kg / h of acid nitrile / ester divided kg

catalyst is in the range 0.01 to 10 h -1 , preferably 0.05 to 2 h "1 .

43-Process according to any one of claims 26 to 40, wherein the second hydrogenation is carried out batchwise batchwise. 44. The method of claim 43, wherein the weight ratio of catalyst relative to the mass of nitrile acid / unsaturated ester is in the range of 0.01 to 1, preferably 0.05 to 0.3, and the reaction time is in the range from 1 h to 24 h, preferably in the range from 3h to 15h.

45. A method according to any one of claims 14 to 44, wherein the reaction mixture resulting from the hydrogenation is subjected to at least one of the following purification steps:

- separation of the catalyst by any means of liquid solid separation;

- the base of separation: in the case of ammonia by evaporation or wash water and in the case of other bases by aqueous washing or tailing in a device during residence time.

- separation of any solvent by evaporation or topping.

46- A method according to any one of claims 14 to 45, characterized in that it further comprises a step of separation of heavy products, in particular secondary amine formed during the hydrogenation, tailing in a device being vacuum residence time, at a pressure in the range of 0.5 to 20 mbar, preferably 1 to 20 mbar, preferably 1 to -5 mbar, at a controlled temperature below 160 ° C, preferably below 140 ° C and preferably below 130 ° C.

47. The method of claim 46, characterized in that the apparatus during residence time is selected from: film evaporators, such as falling film evaporators or thin layer evaporators where the liquid film is created mechanically or by centrifugal force, preferably the thin layer evaporators short path.