The appropriate amount of plasticizer is then added. For the commercial plasticizers DPHP and DIDP, a 50/50 (wt%) mixture is made, denoted "DPHP:DIDP". The solution is stirred for a further 10 min, then poured into a glass Petri dish and left overnight in a fume hood for solvent evaporation. The final material was then placed in a vacuum oven at 50 °C for 6 h to remove the traces of solvent.