Novel dialkyltin oxide composition and method for producing 2-dimethylaminoethyl (meth)acrylate

Abstract

To provide a new, highly concentrated and stable, dialkyl tin oxide catalyst composition, and to provide use of the composition in the synthesis of amino alkyl (meth)acrylates by transesterification from an alkyl (meth)acrylates and an amino alcohol.SOLUTION: The invention relates to a new dialkyl tin oxide catalyst composition and use of the composition in the synthesis of amino alkyl (meth)acrylates by transesterification from an alkyl (meth)acrylates and an amino alcohol, and especially 2-dimethylaminoethyl (meth)acrylate. The invention also relates to polymers made with quaternized amino alkyl (meth)acrylates and use of the polymers in water treatment, sludge dewatering, papermaking process, agriculture, cosmetic and detergency composition, textile process, oil and gas recovery process such as enhanced oil recovery, fracturing, mining operation such as tailings treatment.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to novel dialkyltin oxide catalyst compositions and their use in the synthesis of aminoalkyl(meth)acrylates by transesterification of alkyl(meth)acrylates with aminoalcohols, in particular 2-dimethylaminoethyl(meth)acrylate. [Background technology]

[0002] 2-Dimethylaminoethyl (meth)acrylate monomers are typically quaternized with, for example, methyl chloride, dialkyl sulfates, or benzyl chloride, and then polymerized to produce cationic polymers. These polymers are used in many industries, such as water treatment, papermaking, home and personal care, and oil and gas recovery.

[0003] The use of organotin compounds as catalysts in transesterification reactions is well known. Among the (meth)acrylic esters of interest, 2-dimethylaminoethyl (meth)acrylate can be obtained by the transesterification of alkyl (meth)acrylates with dimethylaminoethanol using tin oxide derivatives, such as dibutyltin oxide (DBTO), as a catalyst. The role of the catalyst is to shift the equilibrium to produce more 2-dimethylaminoethyl (meth)acrylate and reduce the formation of impurities.

[0004] The alkyl (meth)acrylate may be methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, with methyl (meth)acrylate usually being preferred.

[0005] In US Patent No. 7,268,251, the preparation of (meth)acrylates by transesterification is carried out in the presence of a lower titanium alcoholate catalyst. Lower alkoxy titanates such as tetraisopropyl titanate cannot be used in this way. To carry out the alcohol exchange with the amino alcohol of interest, a catalyst preparation process is necessary. This preparation process includes a high-temperature heating stage during which the generated lower alcohol is continuously removed by distillation under vacuum. The implementation of this process is complex, time- and energy-intensive, and generates a waste liquid of lower alcohol that must be disposed of.

[0006] Other suitable catalysts widely described in the literature as effective transesterification catalysts in the synthesis of (meth)acrylate esters are organotin derivatives. In particular, dialkyltin oxides and dialkyltin dichlorides, especially dibutyltin oxide (abbreviated DBTO), are described. Even when DBTO is described as a monomer molecule, the products self-assemble to form clusters of various degrees of polymerization.

[0007] For example, in US Patent No. 3,642,877, DBTO is described as a suitable catalyst for the transesterification of methyl methacrylate with dimethylaminoethanol in the preparation of dimethylaminoethyl methacrylate. Water is a well-known catalyst poison, as it reacts with DBTO. Therefore, the reagent is first azeotropically distilled with methyl methacrylate to remove water before adding DBTO. This reagent drying step is time and energy intensive, requires an excess of methyl methacrylate, and generates waste that must be disposed of. This step also requires further processing of the wet distillate, which is a mixture of methyl methacrylate, water, and methanol. Furthermore, DBTO is used in the process in solid form.

[0008] Furthermore, it is known from the literature that both DBTO and alkyl (meth)acrylates are insoluble in amino alcohols. During the transesterification reaction, there is an induction period before the reaction between the amino alcohol and the (meth)acrylate ester. This induction period reduces the productivity and therefore increases the production costs.

[0009] Without being bound by any theory, it is believed that the induction time is related to the particle size distribution of DBTO. Therefore, those skilled in the art tend to reduce the particle size of DBTO to a powder form. However, doing so may pose a safety risk to users due to inhalation of dust containing toxic tin derivatives.

[0010] To solve this problem, the document US Pat. No. 7,078,560 proposes preactivating the organotin derivatives via the preparation of distannoxane intermediates. A mixture of dialkyltin oxide and dialkyltin dichloride is reacted with dimethylaminoethanol in a solvent. The dialkyltin oxide and dialkyltin dichloride are self-solubilizing without heating. However, a step of evaporating the solvent is necessary to recover the solid distannoxane after filtration. The method disclosed in this document is complicated, especially due to the solvent distillation step and the filtration step that allows the recovery of the distannoxane material. Moreover, the presence of chloride ions can cause corrosion of industrial / manufacturing equipment.

[0011] In the document US 2012 / 0123147 A1, the preparation of a dibutyltin oxide mixture is disclosed by dissolving dibutyltin oxide in a mixture of alcohol and alkyl (meth)acrylate ester or in the presence of aminoalkyl (meth)acrylate ester. This method requires heating the reaction mixture to high temperature for several hours. In addition, the DBTO content is limited to a maximum of 70%.

[0012] In view of the above, the prior art describes various methods for preparing catalysts for the synthesis of aminoalkyl (meth)acrylates.However, these methods are complicated, involve many steps, and consume a lot of energy and time.In addition, these methods generate waste distillates that need to be treated or disposed of.

[0013] Moreover, when adding solid dialkyltin oxide to the reaction mixture, it is necessary to shorten the induction time and improve the productivity of aminoalkyl (meth)acrylate. Fine particles of dialkyltin oxide also pose problems and dangers regarding the exposure of the particles to users and potential health problems. [Prior art documents] [Patent documents]

[0014] [Patent Document 1] U.S. Patent No. 7,268,251 [Patent Document 2] U.S. Patent No. 3,642,877 [Patent Document 3] U.S. Patent No. 7,078,560 [Patent Document 4] US Patent Application Publication No. 2012 / 0123147 [Patent Document 5] U.S. Patent No. 8,186,871 [Patent Document 6] International Publication No. 2011 / 107683 [Patent Document 7] International Publication No. 2016 / 156320 [Patent Document 8] US Patent Application Publication No. 2012 / 0123148 Summary of the Invention [Problem to be solved by the invention]

[0015] Description of the Invention The present invention relates to novel highly concentrated and stable dialkyltin oxide catalyst compositions and their use in the synthesis of aminoalkyl(meth)acrylates by transesterification of alkyl(meth)acrylates and aminoalcohols.

[0016] The present invention further relates to an environmentally friendly process for the preparation of dialkyltin oxides, which does not produce waste products and can be carried out at lower temperatures compared to known processes.

[0017] Surprisingly, it has been found that highly concentrated and stable compositions, preferably suspensions, of dialkyltin oxides can be obtained by means of a specific composition, which is advantageously prepared by a specific method. [Means for solving the problem]

[0018] The present invention relates to - 80% to 90% by weight of dialkyltin oxide, - 5% to 10% by weight of at least one alkyl (meth)acrylate ester, - 5% to 10% by weight of at least one amino alcohol The weight percentages are based on the weight of the composition.

[0019] According to one embodiment, the dialkyltin oxide composition comprises: - 80% to 90% by weight of dialkyltin oxide, - 5% to 10% by weight of at least one alkyl (meth)acrylate ester, - 5% to 10% by weight of at least one amino alcohol In this embodiment, the weight percentages are based on the total weight of the composition and add up to 100%. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020] In the present invention, the alkyl groups of the dialkyltin oxide may be linear, cyclic (substituted or unsubstituted) or branched. The alkyl groups bonded to the tin may be the same or different from each other. The alkyl groups may have a number of carbon atoms comprised between 2 and 12, preferably between 4 and 8, more preferably the alkyl groups are linear and have 4, 8 or 12 carbons.

[0021] In the present invention, the alkyl group of the alkyl (meth)acrylate ester may be linear, cyclic (substituted or unsubstituted) or branched. The alkyl group may have between 1 and 10, preferably between 1 and 8, more preferably between 1 and 4 carbon atoms, and more preferably the alkyl group is methyl or ethyl.

[0022] In the present invention, the dialkyltin oxide is preferably dibutyltin oxide (DBTO).

[0023] In the present invention, amino alcohols correspond to compounds containing a hydroxyl group (-OH) and an amino group on an alkane backbone. The amino functionality is primary (-NH 2 ), second class (-NHR 1 ) or tertiary (-NR 1 R 2 ). This definition includes aminoalcohols in which the hydroxyl and amino functionalities are separated by other chemical groups, such as alkyl, but does not include aminoalcohols in which the hydroxyl and amino functionalities are directly bonded to each other (hydroxylamines). The alkyl group R 1 and R 2 may be the same or different. The alkyl group may have a number comprised between 1 and 8, preferably between 1 and 4, carbon atoms.

[0024] In a preferred embodiment, the dialkyltin oxide composition is a suspension in which 70% to 95% by weight of the dialkyltin oxide is solubilized, and 5% to 30% by weight of the dialkyltin oxide is in the form of particles suspended in the composition. The mass percentages are based on the total amount of dialkyltin oxide in the composition. Preferably, more than 80% to 95% by weight, more preferably more than 85% to 95% by weight, of the dialkyltin oxide is solubilized in the suspension.

[0025] The present invention further relates to a method for producing a dialkyltin oxide composition, comprising the steps of wetting dialkyltin oxide particles with a first wetting solution, grinding and / or slicing the wetted dialkyltin oxide particles in the presence of a second wetting solution to obtain composition A (preferably suspension A), and heating the resulting composition to obtain composition B (preferably suspension B).

[0026] The term "wetting" corresponds to prolonged contact between the dialkyltin oxide particles and the first or second wetting solution. The first and second wetting solutions are not necessarily aqueous.

[0027] The first wetting solution and / or the second wetting solution are preferably organic solvents.

[0028] The first and / or second wetting solution preferably comprises an alkyl (meth)acrylate ester or an amino alcohol, or a mixture of an alkyl (meth)acrylate ester and an amino alcohol. The first and / or second wetting solution preferably comprises a mixture of an alkyl (meth)acrylate ester and an amino alcohol.

[0029] The molar ratio between the alkyl(meth)acrylate ester and the aminoalcohol is advantageously comprised between 1:5 and 5:1, preferably between 1:2 and 2:1.

[0030] The first and second wetting solutions are preferably the same, but may be different.

[0031] In a preferred embodiment, the dialkyltin oxide particles are - a wetting cone for metering dialkyltin oxide particles, the wetting cone being connected to a first wetting solution inlet circuit configured to provide a first wetting solution; - At the bottom of the cone, ·below: - A rotor with knives driven by a motor - Fixed stator with blades a chamber for crushing and discharging the dispersed dialkyltin oxide particles, - a ring supplied by a second wetting solution circuit configured to provide a second wetting solution on all or part of the circumference of the chamber and in communication with the chamber to ensure that the pressurized second wetting solution is sprayed onto the stator blades; The mixture is moistened, crushed and / or sliced ​​in a device comprising:

[0032] This device is preferably a Polymer Slicing Unit (abbreviated PSU) manufactured by SNF and described in documents US 8186871, WO 2011 / 107683 and WO 2016 / 156320, all three of which are incorporated herein by reference, in particular the parts describing the PSU and its uses.

[0033] Composition A is preferably heated for a period ranging from 1 min to 600 min, preferably from 30 min to 180 min, at a temperature preferably comprised between 30°C and 100°C, preferably between 40°C and 90°C.

[0034] The present invention further relates to a process for producing aminoalkyl(meth)acrylates by transesterification of alkyl(meth)acrylates with aminoalcohols, comprising using the composition of the present invention as a catalyst for the transesterification.

[0035] Those skilled in the art know how to carry out the reaction and can refer to US Patent Application Publication No. 2012 / 0123148. The advantage of the method of the present invention is that it does not require any specific additional steps to carry out the reaction of methyl (meth)acrylate and dimethylaminoethanol by transesterification using dialkyltin oxide as catalyst to obtain aminoalkyl (meth)acrylate.

[0036] In a preferred embodiment, the method comprises the steps of: - adding to a reactor at least one aminoalcohol, at least one alkyl (meth)acrylate and at least one solvent in a mass ratio of 2-15:2-40:1-5; - adding to the same reactor a dialkyltin oxide composition according to the invention in an aminoalcohol / dialkyltin oxide composition weight ratio ranging from 10:1 to 100:1 to obtain a composition, preferably a suspension, - raising the temperature of the resulting composition (preferably a suspension) to between 40°C and 70°C for a period of between 30 and 500 minutes in order to recover the aminoalkyl (meth)acrylate whilst continuously removing the lower alkyl alcohol by azeotropic evaporation; - optionally purifying the aminoalkyl(meth)acrylate. Includes.

[0037] The solvents used in the process of the present invention are preferably inert solvents, i.e. solvents that do not react with the amino alcohols and alkyl (meth)acrylates. The solvents are typically alkanes having carbon chains in the range of C6 to C12, which may be linear, cyclic or branched. A suitable solvent is hexane (linear C6H 14 ), which forms an azeotrope with low molecular weight alcohols, especially methanol.

[0038] Purification is preferably carried out by distillation.

[0039] The aminoalkyl(meth)acrylate is preferably 2-dimethylaminoethyl acrylate or 2-dimethylaminoethyl methacrylate.

[0040] The present invention further relates to aminoalkyl(meth)acrylates, in particular 2-dimethylaminoethyl(meth)acrylate, obtainable by the process of the present invention as described above.

[0041] The present invention further relates to quaternized aminoalkyl(meth)acrylates, in particular 2-dimethylaminoethyl(meth)acrylate. Those skilled in the art know how to carry out this quaternization. The quaternization is carried out, for example, with dimethyl sulfate, diethyl sulfate, benzyl chloride or methyl chloride or a mixture thereof, preferably with methyl chloride, to convert the tertiary amine to a quaternary ammonium.

[0042] The present invention further relates to polymers made from quaternized aminoalkyl (meth)acrylates, in particular 2-dimethylaminoethyl (meth)acrylate, thus comprising at least one monomer unit comprising a quaternized aminoalkyl (meth)acrylate.

[0043] The polymer comprises a quaternized 2-dimethylaminoethyl (meth)acrylate and at least one monomer selected from the following list: - non-ionic monomers: acrylamide, methacrylamide, N,N-dimethylacrylamide, N,N-diethylacrylamide, N-vinylpyrrolidone, N-vinylformamide, N-vinylimidazole, methacrylates of polyethylene glycols, diacetone acrylamide, N-isopropylacrylamide, 2-hydroxyethyl acrylate, 2,3-dihydroxypropyl acrylate, 2-hydroxyethyl methacrylate, 2,3-dihydroxypropyl methacrylate, N-tert-butylacrylamide and mixtures thereof; Anionic monomers: non-chlorinated or partially or completely chlorided, acrylic acid, 2-acrylamido-2-methylpropanesulfonic acid (ATBS), methacrylic acid, itaconic acid, maleic acid, allylsulfonate, and mixtures thereof; Cationic monomers: diallyldimethylammonium chloride (DADMAC), acrylamidodialkylaminopropyl, methacrylamidodialkylaminopropyl, dialkylaminoalkyl methacrylates, dialkylaminoalkyl acrylates, dimethylaminoalkyl methacrylates, dimethylaminoalkyl acrylates and their acidified or quaternized salts, and mixtures thereof; - structure directing agents: may be obtained by polymerization with polyethylenically unsaturated monomers (i.e. monomers having at least two unsaturated functional groups, such as vinyl, preferably allyl, acrylic and epoxy functional groups), such as methylenebisacrylamide (MBA), triallylamine, tetraallylammonium chloride, or with macroinitiators, such as polyperoxides, polyazo compounds, and transfer polyagents, such as polymercaptan polymers, and mixtures thereof.

[0044] The alkyl groups of the cationic monomers may be linear, cyclic (substituted or unsubstituted) or branched. The alkyl groups may be the same or different. The alkyl groups may have a number of carbon atoms preferably comprised between 1 and 10, more preferably between 1 and 8, more preferably between 1 and 4, and even more preferably the alkyl groups are methyl or ethyl.

[0045] Any polymerization method may be used, such as gel polymerization, liquid phase or emulsion polymerization. The polymer may be obtained in any form, such as powder, emulsion, dispersion or solution. The polymers of the present invention are preferably water-soluble, but may also be water-swellable.

[0046] The polymer according to the present invention is not limited with respect to molecular weight. The polymer preferably has an average molecular weight comprised between 5,000 g / mol and 100,000 g / mol, or an average molecular weight comprised between 100,000 g / mol and 1,000,000 g / mol, or an average molecular weight comprised between 1,000,000 g / mol and 30 million g / mol. The average molecular weight by weight is preferably measured by gel permeation chromatography (GPC).

[0047] The present invention further relates to the use of the polymers of the present invention in water treatment, sludge dewatering, paper manufacturing processes, agriculture, cosmetic and cleaning compositions, textile processes (also referred to as fiber treatment processes, fiber processing processes, fabric treatment processes, textile processing processes, etc.), oil and gas recovery processes such as enhanced oil recovery, fracturing and mining operations such as tailings treatment.

[0048] The present invention further relates to the use of the polymers of the present invention as dispersants, coagulants, flocculants, thickeners, grinding agents, drag reducers, superabsorbents.

[0049] The present invention provides novel and unique highly concentrated and stable compositions (preferably suspensions) of dialkyltin oxides that can be efficiently used as catalysts in the transesterification of alkyl(meth)acrylates and aminoalcohols to produce aminoalkyl(meth)acrylates, preferably 2-dimethylaminoethyl(meth)acrylate.

[0050] The novel composition of dialkyltin oxide can enhance the transesterification reaction. The reaction is simple, consumes less energy, and generates less waste liquid. In addition, the use of the novel composition can shorten the induction time and reaction time, improving the productivity of aminoalkyl (meth)acrylate. Finally, the absence of fine particles of DBTO (less than 2000 μm, usually less than 1000 μm) solves the danger and health problems for users of dialkyltin oxide.

[0051] The average particle diameter of the composition of the invention is preferably comprised between 200 μm and 2000 μm, more preferably between 300 μm and 1500 μm.

[0052] The invention will now be described in more detail by the following examples. EXAMPLES

[0053] (Counterexample 1) As described in US Patent Application Publication No. 2012 / 0123148, solid DBTO having a particle size distribution of 300 μm is used as a catalyst in the production of 2-dimethylaminoethyl acrylate by transesterification of methyl acrylate with dimethylaminoethanol.

[0054] (Counterexample 2) The same procedure as in counter example 1 is carried out using solid DBTO with a particle size distribution of 150 μm.

[0055] (Examples according to the present invention) As described in US Patent No. 8,186,871, solid DBTO with a particle size distribution of 300 μm is loaded into the wetting cone of a PSU device supplied by SNF. A first wetting solution consisting of a mixture of methyl acrylate and dimethylaminoethanol (1:1 by weight) is added to the lower part of the wetting cone (first inlet circuit) and a second wetting solution identical to the first is sprayed into the grinding chamber to obtain a suspension containing 85% by weight of dialkyltin oxide. The suspension obtained is transferred to a container and heated at 80° C. for 120 minutes with gentle stirring. The suspension obtained is stable. The dialkyltin oxide contained in the suspension is solubilized in a proportion of 90% w.

[0056] The resulting suspension of DBTO is used as a catalyst in the transesterification of methyl acrylate with dimethylaminoethanol to produce 2-dimethylaminoethyl acrylate, as described in US Patent Application Publication No. 2012 / 0123148.

[0057] The reaction parameters are listed in Table 1.

[0058] [Table 1]

[0059] The reduction in particle size in counter example 2 allows for a shorter induction time and a slightly shorter reaction time, but raises health concerns with the DBTO powder.

[0060] The use of the DBTO composition of the present invention allows for a significant reduction in induction time without the drawbacks of powder as in Counter Example 2, a 20% reduction in reaction time, and better yields.

[0061] Similar performance is observed when methyl acrylate is substituted for methyl methacrylate.

[0062] The corresponding monomers obtained by the process of the present invention are quaternized and used to produce copolymers (20 mol % / 80 mol %) of acrylamide and aminoalkyl (meth)acrylate in quaternized form, said polymers being successfully used to flocculate wastewater.

Claims

1. 80% to 90% by weight of dialkyltin oxide; 5% to 10% by weight of at least one alkyl (meth)acrylate ester; 5% to 10% by weight of at least one amino alcohol wherein the weight percentages are based on the weight of the dialkyltin oxide composition.

2. 2. The dialkyl tin oxide composition of claim 1, wherein the composition is a suspension in which 70% to 95% by weight of the dialkyl tin oxide is solubilized and 5% to 30% by weight of the dialkyl tin oxide is in the form of particles suspended in the composition, the weight percentages being based on the weight of dialkyl tin oxide in the dialkyl tin oxide composition.

3. 2. The dialkyltin oxide composition of claim 1, wherein the dialkyltin oxide is dibutyltin oxide (DBTO).

4. 10. A method for producing a dialkyl tin oxide composition according to claim 1, comprising the steps of wetting dialkyl tin oxide particles with a first wetting solution, grinding and / or slicing the wetted dialkyl tin oxide particles in the presence of a second wetting solution to obtain suspension A, and heating the resulting suspension to obtain suspension B.

5. The method of claim 4, wherein the first and / or the second wetting solution comprises an alkyl (meth)acrylate ester or an amino alcohol, or a mixture of an alkyl (meth)acrylate ester and an amino alcohol.

6. The dialkyltin oxide particles are a wetting cone for metering dialkyltin oxide particles, the wetting cone being connected to a first wetting solution inlet circuit configured to provide a first wetting solution; At the lower end of the cone below: A rotor with knives driven by a motor Fixed stator with blades a chamber for crushing and discharging the dispersed dialkyltin oxide particles, a ring supplied by a second wetting solution circuit configured to provide a second wetting solution on all or part of the circumference of the chamber and in communication with the chamber to ensure that the pressurized second wetting solution is sprayed onto the stator blades; The method according to claim 4, wherein the wetting, grinding and / or slicing are carried out in an apparatus comprising:

7. 5. The method according to claim 4, wherein said suspension A is heated at a temperature comprised between 30° C. and 100° C. for a period ranging from 1 min to 600 min.

8. 13. A method for producing an aminoalkyl(meth)acrylate by transesterification of an alkyl(meth)acrylate with an aminoalcohol, comprising using the dialkyltin oxide composition of claim 1 as a catalyst for transesterification.

9. adding to a reactor at least one aminoalcohol, at least one alkyl (meth)acrylate, and at least one solvent in a weight ratio of 2-15:2-40:1-5; adding to the same reactor a dialkyltin oxide composition according to any one of claims 1 to 3 in a weight ratio of amino alcohol to said dialkyltin oxide composition in the range of 10:1 to 100:1 to obtain a suspension; increasing the temperature of the resulting suspension to between 40° C. and 70° C. for a period of between 30 and 500 minutes in order to recover the aminoalkyl (meth)acrylate whilst continuously removing the lower alkyl alcohol by azeotropic evaporation; A step of obtaining aminoalkyl (meth)acrylate 9. The method of claim 8, comprising:

10. 10. The method of claim 9, further comprising the step of purifying the aminoalkyl(meth)acrylate.

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