Table 2 shows the mechanical properties of the different films.
Based on the E and EAB values, PLA films with no additives incorporated
can be mechanically described as stiff and brittle, respectively.
In addition, the decreased observed in TS when Proallium®
was incorporated was significant (p < 0.05) in the 5 and 6.5% of
Proallium® groups. The reduction in the elongation and elastic
modulus observed were related to the concentration of Proallium®.
For instance, a decrease of 26.66e40% was found for the films with
the highest contents of Proallium®. This means that PLA films with
Proallium® were less stiff and more fragile, although PLA films are
quite fragile themselves. Similar effects on the mechanical properties
have been observed in PLA materials incorporating different
antioxidants (ascorbyl palmitate, a-tocopherol and butylated
hydroxytoluene) (Byun et al. 2010; Jamshidian et al., 2012). In
addition, essential oils are usually liquid at room temperature, and
their presence in the film structure in the form of oil droplets can
easily be deformed, enhancing film flexibility (Ahmad et al., 2012).