How can plasticizers be used as emulsion modifiers for adhesives?
In compounding waterborne adhesives, the formulator can modify the system by adding a plasticizer. In general, the addition of selected plasticizers can increase viscosity, reduce the glass transition temperature (Tg), and increase T-peel strength, especially in a PVA system. Another purpose in adding a plasticizer is to extend its open or working time properties. Open time was judged as the time at which the adhesive became too dry to form a paper-tearing bond. The open time of all plasticized systems was observed to be equal to or greater than the open time for unplasticized base polymer. For information on a study conducted at Eastman, see publication WA-30.
