Abstract: The invention relates to the production of (meth)acrylic esters according to a process by direct esterification, and in particular to the purification of a crude reaction mixture comprising a C4-C12 (meth)acrylic ester using a dividing wall column employed in a particular configuration. The dividing wall column is equipped with a separating wall creating separation zones in the column, the wall not being joined to the upper dome of the column in the top part and being joined to the bottom of the column in the bottom part. The process according to the invention guarantees a product of very high purity, independently of the back-cracking reactions of the heavy by-products liable to arise during the purification of the product sought.

Abstract: The present invention relates to the use of a stabilizing composition comprising at least one N-oxyl compound and at least one polymerization inhibitor other than an N-oxyl compound, for inhibiting transesterification catalyst degradation in a process for the synthesis of aminoalkyl (meth)acrylates. Preferably, the transesterification catalyst is a titanium organometallic compound and the stabilising composition comprises at least one N-oxyl derivative and at least one polymerization inhibitor chosen from phenolic compounds and phenothiazine compounds in a weight ratio of between 1 and 10, preferably between 4 and 10, limits inclusive.

Abstract: A method of stabilizing radical ethylene copolymerization reactions for approximately 5 to 10 minutes, the method including using a phenolic compound with other comonomers and performing the radical ethylene copolymerization reactions at high pressure. Also, a method of preparing an ethylene copolymer at high pressure in the presence of one or more phenolic compounds, as defined below, and one or more initiators.

Abstract: The invention relates to the production of (meth)acrylic esters according to a process by direct esterification, and in particular to the purification of a crude reaction mixture comprising a C4-C12 (meth)acrylic ester using a dividing wall column employed in a particular configuration. The dividing wall column is equipped with a separating wall creating separation zones in the column, the wall not being joined to the upper dome of the column in the top part and being joined to the bottom of the column in the bottom part. The process according to the invention guarantees a product of very high purity, independently of the back-cracking reactions of the heavy by-products liable to arise during the purification of the product sought.

Abstract: The present invention relates to the use of a stabilizing composition comprising at least one N-oxyl compound and at least one polymerization inhibitor other than an N-oxyl compound, for inhibiting transesterification catalyst degradation in a process for the synthesis of aminoalkyl (meth)acrylates. Preferably, the transesterification catalyst is a titanium organometallic compound and the stabilising composition comprises at least one N-oxyl derivative and at least one polymerization inhibitor chosen from phenolic compounds and phenothiazine compounds in a weight ratio of between 1 and 10, preferably between 4 and 10, limits inclusive.

Abstract: This invention produces technical (meth)acrylic acid without being confronted with problems of fouling of systems to purify the crude reaction mixture of (meth)acrylic acid synthesis, due to the presence of glyoxal formed during synthesis. The invention is based on the addition or generation of quinoline derivative in a glyoxal-containing (meth)acrylic acid flow in a quinoline/glyoxal derivative molar ratio ranging from 0.1 to 5, during the purification steps, said quinoline compound with one of formulas (I) or (II): wherein, groups R1, R2, R3, and R4 independently denote a hydrogen atom or a C1-C6, or R1 et R2 C-alkyl group combine and together with the atoms to which they are attached, form a saturated or unsaturated ring or heterocycle, preferably a phenyl group, and/or R3 and R4 combine and with the atoms to which they are attached, form a saturated or unsaturated ring or heterocycle, preferably a phenyl group.

Abstract: The present invention relates to the use of one or more phenolic compounds, as defined below, to stabilise ethylene copolymer reactions at high pressure. The invention also relates to a method of preparing an ethylene copolymer at high pressure in the presence of one or more phenolic compounds, as defined below, and one or more initiators.

Abstract: This invention produces technical (meth)acrylic acid without being confronted with problems of fouling of systems to purify the crude reaction mixture of (meth)acrylic acid synthesis, due to the presence of glyoxal formed during synthesis. The invention is based on the addition or generation of quinoline derivative in a glyoxal-containing (meth)acrylic acid flow in a quinoline/glyoxal derivative molar ratio ranging from 0.1 to 5, during the purification steps, said quinoline compound with one of formulas (I) or (II): wherein, groups R1, R2, R3, and R4 independently denote a hydrogen atom or a C1-C6, or R1 et R2 C-alkyl group combine and together with the atoms to which they are attached, form a saturated or unsaturated ring or heterocycle, preferably a phenyl group, and/or R3 and R4 combine and with the atoms to which they are attached, form a saturated or unsaturated ring or heterocycle, preferably a phenyl group.

Abstract: The invention relates to a method for producing a (meth)acrylic ester with improved productivity, by transesterfication of a light alkyl (meth)acrylate with a heavy alcohol. The method of the invention includes the recycling of noble products recovered after the thermal treatment of heavy fractions generated during the synthesis, said thermal treatment being carried out in the presence of a dialkyl phthalate, the alkyl chain of which corresponds to that of the light alkyl (meth)acrylate. The invention applies to the production of N,N-dimethyaminoethyl acrylate from ethyl acrylate.

Abstract: The invention relates to a method for producing a (meth)acrylic ester with improved productivity, by transesterfication of a light alkyl (meth)acrylate with a heavy alcohol. The method of the invention includes the recycling of noble products recovered after the thermal treatment of heavy fractions generated during the synthesis, said thermal treatment being carried out in the presence of a dialkyl phthalate, the alkyl chain of which corresponds to that of the light alkyl (meth)acrylate. The invention applies to the production of N,N-dimethyaminoethyl acrylate from ethyl acrylate.