New developments in emulsion–PVC polymerisation to produce polymers with the potential of reduced or zero VOC requirements when used in plastisol applications

Poly(vinylchloride) (chloroethene) resins have been used for the preparation of plastisols for a number of years. PVC plastisols are dispersions of such resins in liquid plasticisers, the plasticiser having the dual function of imparting softness and flexibility to the final article and for providing a liquid medium for the preparation of the plastisol that enables it to be coated, dipped or sprayed. For many years plastisol viscosity modification has involved the use of various volatile organic compounds (VOCs), which have an impact on their use in the workplace, and can also cause emitted VOCs from the end product. Control of the latter is of particular interest in new developments to combat indoor air quality (IAQ) problems. This paper shows that newly developed PVC resins are capable of producing the correct plastisol viscosity without the need for VOC addition to the plastisol. Moreover, new PVC additive technologies are available which enable end articles to be made from PVC plastisols that show greatly reduced or zero impact on IAQ when tested with newly developed equipment such as the Field and Laboratory Emission Cell (FLEC).