| 摘要 |
A transesterification process produces a (meth)acrylate ester product from a mixture comprising an alkyl(meth)acrylate reactant, an alcohol reactant, a catalyst, and a polymerization inhibitor, wherein the water content in the reaction zone at the start of the transesterification step is from 0.2 to 1.1 weight percent, based on the weight of the materials in the reaction zone. The mixture is subjected to reaction conditions sufficient to produce a product (meth)acrylate and a product alcohol, which are different than the reactants. |
| 主权项 |
1. A process for producing (meth)acrylate monomers, the process comprising:
a) forming a mixture by admixing: a1) reactant alkyl (meth)acrylate; a2) from 10 to 10,000 parts per million by weight, based on the weight of the reactant alkyl (meth)acrylate, of a free radical polymerization inhibitor; and a3) optionally, a reactant alcohol and/or a catalyst: b) if the mixture contains more than 1.1 weight percent water, then dehydrating the mixture so that it contains from 1.0 to 1.1 weight percent water, based on the weight of the mixture; c) adding reactant alcohol and/or catalyst to the mixture, as needed, such that the molar ratio of reactant alcohol to reactant alkyl (meth)acrylate is from 1:1 to 1:20, and such that the catalyst is present in a catalytic amount; d) reacting the reactant alcohol with the reactant alkyl (meth)acrylate in a reaction zone at a temperature of from 70 to 125° C. and a pressure of from 100 mm Hg (13.3 kPa) to 900 mm Hg (120.0 kPa), with the proviso that the water content in the reaction zone at the start of this step is from 1.0 to 1.1 weight percent, based on the weight of the materials in the reaction zone; e) creating a crude product by removing a mixture of alkyl (meth)acrylate and alcohol; f) optionally adding water to enable recycling of the catalyst; g) optionally recycling the reactant alkyl (meth)acrylate; and h) optionally distilling the crude product;wherein the catalyst is selected from the group consisting of dibutyl tin oxide, lithium carbonate, and lithium hydroxide. |
