Abstract: Set forth is a process for preparing acrylic acid and/or the ester of acrylic acid and lactic acid from a lactic acid oligomer or polymer. As a result of the use of a bromide source and/or a chloride source in combination with a specific acid, a process that can be operated to obtain a high yield, and is relatively easy to perform, is realized.

Abstract: A process for preparing acrylic acid and/or the ester of acrylic acid and lactic acid from a lactic acid oligomer or polymer, comprising the steps of bringing a reaction mixture comprising the lactic acid oligomer or polymer to reaction conditions to form acrylic acid and/or the ester of acrylic acid and lactic acid, the reacting mixture comprising a halide source selected from a bromide source and/or a chloride source and optionally an acid selected from the group of acids with a pKa of at most 2.0 and compounds which under reaction conditions decompose under the formation of an acid with a pKa of at most 2.0, with the reaction mixture comprising less than 1 wt. % of water, and keeping the reaction mixture under reaction conditions for a time sufficient to produce acrylic acid and/or the ester of acrylic acid and lactic acid.