What Is an Acrylic Reactor: Polymerization Chemistry, Design and Control Answering the core question: What is an acrylic reactor? An acrylic reactor is a stirred vessel in which acrylic and methacrylic monomers such as acrylic acid, butyl acrylate, methyl methacrylate and styrene are polymerised by a free radical mechanism into acrylic resins, emulsions or elastomers. The reaction is strongly exothermic, releasing 60-80 kJ per mole of monomer, which is roughly 700-1,100 kJ