Thermo-sealed packages tightness is an essential property to ensure its function for both domestic and industrial used products. Tightness is determined by inherent characteristics of packaging
material and product’s nature. Table 2 shows WVP values corresponding to the studied TPS-talc bionanocomposite films, deter-mined by gravimetric method, as well as by measurement of gas
flow. Comparing to synthetic polymers, TPS films shows a higher WVP attributed to two contributions. One of them is related to the inherent hydrophilic nature of starch and the other is associated to
the swelling capability of starcheglycerol network which can hold substantial amounts of water. Swelling phenomenon disrupts matrix structural integrity affecting film barrier properties
(Pushpadass et al., 2009). Talc addition at 1% w/w did not significantly modify (p < 0.05) moisture vapor permeability of TPS films. From both methods a WVP decrease of 1.4 times was observed for
talc concentration of 3% w/w. For talc addition of 5% w/w, reduction percentages were 26 and 54% determined gravimetrically and by gas flow measurements, respectively. Despite obtained values using
both techniques were significantly different, WVP tendency as a function of talc concentration resulted similar. These results indicate that layered talc structure hindered the transmission of
moisture vapor through composite films. Similar results were