Methacrylate monomers for Plastics
PVC plastisols are PVC powder emulsions in plasticizers, e.g. aromatic or aliphatic dicarbonic esters. Depending on the application envisaged and properties required, PVC/plasticizer ratios vary between 80:20 and 50:50. Without additives, PVC plastisols show only moderate adhesion to polar substrates, such as metal. Partially substituting the plasticizer with multifunctional methacrylates causes a substantial improvement in plastisol adhesion to these substrates. Moreover, peroxides added for plastisol gelation effectively initiate polymerization of the multifunctional methacrylates. This in turn leads to increased hardness and higher tensile strength in the end product.
Shore hardness also depends on the type of multifunctional methacrylate used. It decreases in this order by up to 40% at the same monomer content: VISIOMER® 1,3-BDDMA > EGDMA > TRGDMA > PEG 200 DMA.
The main applications for PVC plastisols containing multifunctional methacrylates as adhesion promoters and hardeners include the following: anti-noise compounds, car underseals, finish compounds for PVC flooring, and coil coatings.