# US 10,479,757 B2 · N,N-dimethylaminoethyl acrylate composition stabilized in respect of discoloring effects

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 10,479,757 B2
- Document ID: US10479757B2
- Status: Granted
- Kind: B2
- Application number: 16/096,305
- Filed: 2017-04-24
- Published: 2019-05-09
- Granted: 2019-11-19
- Earliest claimed: 2016-04-28
- Assignees: Arkema France
- Applicants: Arkema France
- Inventors: Fanny Dubut; Benoit Riflade; Sandra Maget
- Web page: https://patentgrep.com/patent/US10479757B2

## CPC

- C07C 213/10: Separation; Purification; Stabilisation; Use of additives
- B01D 3/10: Vacuum distillation (B01D3/12 takes precedence)
- B01D 3/143: {by two or more of a fractionation, separation or rectification step}
- C07C 213/08: by reactions not involving the formation of amino groups, hydroxy groups or etherified or esterified hydroxy groups
- C07C 219/08: having at least one of the hydroxy groups esterified by a carboxylic acid having the esterifying carboxyl group bound to an acyclic carbon atom of an acyclic unsaturated carbon skeleton
- C08K 5/08: Quinones
- C08K 5/175: {containing COOH-groups; Esters or salts thereof}
- C07C: ACYCLIC OR CARBOCYCLIC COMPOUNDS
- B01D: SEPARATION (separating solids from solids by wet methods B03B, B03D; by pneumatic jigs or tables B03B; by other dry methods B07; magnetic or electrostatic separation of solid materials from solid materials or fluids, separation by high-voltage electric fields B03C; centrifuges, vortex apparatus B04; presses per se for squeezing-out liquid from liquid-containing material B30B9/02; treatment of water C02F, e.g. softening by ion-exchange C02F1/42; {arrangements of air intake cleaners in gas turbine plants F02C7/05} ; arrangements or mounting of filters in air-conditioning, air-humidification or ventilation F24F13/28)
- C08K: Use of inorganic or non-macromolecular organic substances as compounding ingredients (paints, inks, varnishes, dyes, polishes, adhesives C09)

## Abstract

The invention relates to the use of 2,6,-di-tert-butyl-4-methylphenol at a moiety of 25 to 200 ppm for stabilizing N,N-dimethylaminoethyl acrylate in respect of discoloring effects. The invention also relates to an N,N-dimethylaminoethyl acrylate stabilized in said manner and to a method for producing the same.

## Claims

### Claim 1

A process for the continuous production of a composition of N,N-dimethylaminoethyl acrylate that is stabilized with respect to coloration, comprising from 25 to 200 ppm of 2,6-di-tert-butyl-4-methylphenol, said process comprising the steps of transesterifying a light acrylate selected from the group consisting of methyl acrylate and ethyl acrylate, with dimethylaminoethanol in the presence of a catalyst, followed by a treatment for purifying a reaction mixture comprising a final distillation of purified N,N-dimethylaminoethyl acrylate, wherein 25 to 200 ppm of 2,6-di-tert-butyl-4-methylphenol are introduced at an outlet of the distilled gaseous stream of purified N,N-dimethylaminoethyl acrylate, before condensation of final product.

### Claim 2 (depends on 1)

The process of claim 1 comprising the following steps:
a) transesterifying a light acrylate selected from the group consisting of methyl acrylate and ethyl acrylate, with dimethylaminoethanol in the presence of a transesterification catalyst and at least one polymerization inhibitor, a corresponding azeotropic mixture of light acrylate/light alcohol being drawn off continuously during the reaction;
b) conveying a crude reaction mixture to a first distillation column C1, referred to as tailing column, under reduced pressure, the crude reaction mixture comprising the desired N,N-dimethylaminoethyl acrylate with, as light products, dimethylaminoethanol and unreacted light acrylate and, as heavy products, the catalyst, the polymerization inhibitor(s) and heavy reaction by-products, to obtain:
at the top, a stream composed essentially of N,N-dimethylaminoethyl acrylate and light products, comprising a minor fraction of heavy products but devoid, or substantially devoid, of catalyst; and
at the bottom, a stream composed of heavy products with a minor fraction of N,N-dimethylaminoethyl acrylate and the catalyst; then
c) conveying the top stream from the first distillation column C1 to a second distillation column C2, referred to as topping column, under reduced pressure, to obtain:
at the top, a stream composed of light products with a minor fraction of N,N-dimethylaminoethyl acrylate; and
at the bottom, N,N-dimethylaminoethyl acrylate containing traces of light products, heavy reaction by-products and the polymerization inhibitor(s); then
d) conveying the bottom stream from the second distillation column C2 to a third distillation column C3, referred to as rectification column, under reduced pressure, into the top of which 25 to 200 ppm of 2,6-di-tert-butyl-4-methylphenol is introduced, to obtain:
at the top, a gaseous stream of purified N,N-dimethylaminoethyl acrylate that is stabilized with respect to coloration which is subsequently condensed; and
at the bottom, a stream consisting essentially of the polymerization inhibitor(s).

### Claim 3 (depends on 1)

The process as claimed in claim 1 wherein the light acrylate is ethyl acrylate.

### Claim 4 (depends on 1)

The process of claim 1 wherein the composition has a coloration of less than 100.

### Claim 5 (depends on 1)

The process of claim 1 wherein the composition further comprises at least one polymerization inhibitor, selected from the group consisting of hydroquinone, hydroquinone methyl ether (MEHQ) and mixtures thereof.