Chemical crosslinking during film formation
The change in surface pH of drying films was measured using pH indicator paper at the surface as a function of time until the touch-dry point. Gravimetric gel fraction measurements were performed on 1 lm films bar-cast on silicon substrates via the extraction of the soluble portion using acetone. The change in percentage gel with drying time was measured as a function of particle size, film thickness, and level of crosslinker.