To prepare film-forming solution, the solution (14% (w/w)) was
then mixed with GLY as a plasticizer in 25%, 35%, and 50% (w/w)
based on BSG weight. Following the addition of GLY, stirring was
continued for a further 15 min at 55◦C. The film-forming solutions
were degassed under vacuum for 5 min to remove bubbles that
could become pinholes after drying up. BSG films were cast by
pouring the mixture onto a Teflon plate placed on a leveled gran-
ite surface for approximately 18 h at room temperature and room
relative humidity. Dried films were peeled off the casting surface
and stored inside desiccators at 25 ± 1◦C until the evaluation phase.
Films were conditioned at room temperature (25◦C) and 53% RH in
chambers containing saturated solutions of Mg(NO3)2prior to all
analyzes.