Process for producing tau-butyl methacrylate

摘要

A process for producing methacrylic acid which comprises reacting methacrylic acid and isobutylene in the presence of a sulfonic acid group-containing ion exchange resin by a continuous process while controlling the reaction at a reaction temperature of -20 DEG C. to +20 DEG C. so as to fulfil the following relation: y<100-50x wherein x is the ratio of the total molar number of isobutylene and its reaction products to the total molar number of methacrylic acid and its reaction products and y is conversion (%) of isobutylene, followed by degassing the unreacted isobutylene, distilling off the low boiling substances by distillation under reduced pressure, and then sending the remainder to a t-butyl methacrylate purifying tower where a product of high purity is obtained from the distillate side and unreacted methacrylic acid is withdrawn from the tower bottom side and circulated into the reaction step.