Sulfobetaine monomers, process for preparing same, and uses thereof
The invention relates to a novel sulfobetaine monomer and to a process for the preparation thereof, advantageously by reaction between a vinyl-amine compound and a vinyl-sulfonic acid compound, preferably in the presence of a solubilizing agent. The invention also relates to the (co)polymers obtained from this novel type of sulfobetaine monomer, and to the use thereof, for example as a flocculant, dispersing agent, thickening agent, absorbent agent or friction-reducing agent.
1 . A process for preparing a sulfobetaine monomer of formula (V) and/or its acid form comprising reacting:
a compound of formula (VI), and
a compound of formula (VII) and/or one of its salts,
optionally in the presence of at least one solubilizing agent of the compound of formula (VII), and
in the presence of at least one solvent, wherein the said solvent is a compound having a melting temperature below 15° C.,
wherein the reaction is carried out with an amount of polymerization inhibitor of between 10 and less than 500 ppm relative to the total mass of the compounds of formulas (VI) and (VII),
In formulas (V), (VI) and (VII):
R 1 and R 4 are, independently of each other, —H or —CH 3 ,
R 2 and R 3 are, independently of each other, a linear C1-C10 alkyl or branched C3-C10 alkyl or linear C2-C10 alkylene group,
R 5 is —H, or a linear C1-C22 alkyl or branched C3-C22 alkyl group, or R 5 forms with R 6 a C4-C10 carbon ring, optionally branched,
R 6 is a linear C1-C22 alkyl or branched C3-C22 alkyl group, or R 6 forms with R 5 a C4-C10 carbon ring, optionally branched,
X 1 =—COO—, or —CONH— or —CH 2 —,
X 2 =—COO— or —CONH—,
n is an integer between 0 and 10,
wherein
the compound of formula (VI) is chosen from dimethylaminopropyl methacrylamide, dimethylaminopropyl acrylamide, allyldimethylamine, diallylmethyl amine, dimethylaminoethyl methacrylate, and dimethylaminoethyl acrylate;
the compound of formula (VII) is 2-acrylamido-2-methylpropane sulfonic acid and/or one of its salts; and
the polymerization inhibitor is mono methyl ether of hydroquinone (MEHQ),
and wherein said process comprises carrying out the following steps:
a1) adding to a stirred reactor at least one compound of the formula (VI), optionally at least one solubilizing agent of the compound of the formula (VII), and the at least one solvent to obtain a pre-reaction mixture;
a2) adding at least one compound of the formula (VII) and/or one of its salts to the pre-reaction mixture;
a3) after reaction, obtaining sulfobetaine monomers of the formula (V) and/or its acid form in the form of a solution;
a4) extracting the compound of the formula (V) in the form of crystals AA;
a5) combining the crystals AA of the compound of formula (V) with an aqueous solution to form a suspension A;
a6) mixing suspension A for a period of between 1 minute and 20 hours;
a7) obtaining a suspension B of crystals BB of the compound of formula (V) in a hydrated form; and
a8) optionally isolating the crystals BB obtained from suspension B.
2 . A process for preparing a sulfobetaine monomer of formula (V) and/or its acid form comprising reacting:
a compound of formula (VI), and
a compound of formula (VII) and/or one of its salts,
optionally in the presence of at least one solubilizing agent of the compound of formula (VII), and
in the presence of at least one solvent, wherein the said solvent is a compound having a melting temperature below 15° C.,
wherein the reaction is carried out with an amount of polymerization inhibitor of between 10 and less than 500 ppm relative to the total mass of the compounds of formulas (VI) and (VII),
In formulas (V), (VI) and (VII):
R 1 and R 4 are, independently of each other, —H or —CH 3 ,
R 2 and R 3 are, independently of each other, a linear C1-C10 alkyl or branched C3-C10 alkyl or linear C2-C10 alkylene group,
R 5 is —H, or a linear C1-C22 alkyl or branched C3-C22 alkyl group, or R 5 forms with R 6 a C4-C10 carbon ring, optionally branched,
R 6 is a linear C1-C22 alkyl or branched C3-C22 alkyl group, or R 6 forms with R 5 a C4—C10 carbon ring, optionally branched,
X 1 =—COO—, or —CONH— or —CH 2 —,
X 2 =—COO— or —CONH—,
n is an integer between 0 and 10,
wherein
the compound of formula (VI) is chosen from dimethylaminopropyl methacrylamide, dimethylaminopropyl acrylamide, allyldimethylamine, diallylmethyl amine, dimethylaminoethyl methacrylate, and dimethylaminoethyl acrylate;
the compound of formula (VII) is 2-acrylamido-2-methylpropane sulfonic acid and/or one of its salts; and
the polymerization inhibitor is mono methyl ether of hydroquinone (MEHQ),
and wherein said process comprises carrying out the following steps:
a1) adding to a stirred reactor at least one compound of the formula (VI), optionally at least one solubilizing agent of the compound of formula (VII), and the at least one solvent to obtain a pre-reaction mixture;
a2) adding at least one compound of the formula (VII) and/or one of its salts to the pre-reaction mixture;
a3) after reaction, obtaining sulfobetaine monomers of the formula (V) and/or its acid form in the form of a suspension of crystals AA;
a5) combining the crystals AA of the compound of the formula (V) with an aqueous solution to form a suspension A;
a6) mixing suspension A for a period of between 1 minute and 20 hours;
a7) obtaining a suspension B of crystals BB of the compound of the formula (V) in a hydrated form; and
a8) optionally isolating the crystals BB obtained from suspension B.