Does Plasticizer Penetrate Tightly Bound Polymer in Adsorbed Poly(vinyl acetate) on Silica?

When only tightly bound poly(vinyl acetate) (PVAc) was adsorbed on silica, the plasticizer, di(propylene glycol) dibenzoate (DPGDB), was not effective in lowering its glass transition. To determine why the plasticizer was not effective, we probed the behavior of the deuterated plasticizer di(propylene glycol) dibenzoate (DPGDB-d10)/PVAc/silica system using deuterium (2H) solid state NMR and temperature-modulated differential scanning calorimetry...