Patent ID: 6897336

Claim:
A method of esterification or transesterification, comprising: reacting (meth)acrylic acid with an alcohol or a (meth)acrylic acid ester with an alcohol, each in the presence of a catalyst, the esterification or transesterification reaction being conducted under conditions which at least suppress the polymerization of (meth)acrylate compounds by one of the following techniques: a) thermally treating the alcohol reactant in the absence of water before the esterification or transesterification reaction and then formulating an esterification or transesterification reaction medium containing the heat treated alcohol and a polymerization inhibitor in an amount of at least 0.2 mmol per kg of heat treated alcohol and per meq/kg of the peroxide number of the alcohol determined by the Sully method; or b) thermally treating the alcohol reactant in the absence of water before the esterification or transesterification reaction and then conducting the esterification or transesterification reaction in a medium containing the heat treated alcohol; or c) thermally treating the alcohol reactant in the absence of water before the esterification or transesterification reaction and then metering the (meth)acrylic acid or (meth)acrylic ester reactant into a reactor at a rate of less than 250 g per hour and liter of reactor volume which contains reaction medium comprising the thermally treated alcohol; or d) metering the (meth)acrylic acid or (meth)acrylic ester reactant into a reactor at a rate of less than 250 g per hour and liter of reactor volume which contains a reaction medium; or e) metering the (meth)acrylic acid or (meth)acrylic ester reactant into a reactor at a rate of less than 250 g per hour and liter of reactor volume which contains a reaction medium comprising an alcohol and at least 0.2 mmol of polymerization inhibitor per kg of alcohol and per meq/kg of peroxide number of the alcohol determined by the Sully method; or f) thermally treating the alcohol reactant in the absence of water before the esterification or transesterification reaction, formulating an esterification or transesterification reaction medium containing the heat treated alcohol and a polymerization inhibitor in an amount of at least 0.2 mmol per kg of heat treated alcohol and per meq/kg of the peroxide number of the alcohol determined by the Sully method and then metering the (meth)acrylic acid or (meth)acrylic ester reactant into a reactor at a rate of less than 250 g per hour and liter of reactor volume.