In this work, we prepared and characterized water insoluble Tara gum films.
Tara gum (TG) is a polysaccharide extracted from the endosperm of Caesalpinia
spinosa seeds with a performance of 12% wt. TG films were evaluated as barrier
material for agricultural and food industries. The films were modified in order to
improve water resistance by using glutaraldehyde (Glu) as crosslinker. The
crosslinking process consisted of placing the TG films in a bath containing Glu in an
acidic medium for a period of 12 and 24 hours (TG-12 and TG-24) at 25ºC. Film
properties were structurally studied through XRD, TGA and SEM images and
operationally evaluated by measuring water vapor permeability (WVP), gas permeation
and mechanical properties. WVP values decreased with increasing crosslinking time.
This is due to crosslinking which hinders the diffusion of vapor molecules through the
polymer matrix. Gas permeability tests showed permeabilities in the order CO2>> N2>
O2. Mechanical tests indicated an increase in the elastic modulus of the film with
increasing crosslinking time; this effect is due to the loss of flexibility of the
crosslinked polymeric matrix.
Keywords: Films, Gas permeation, Mechanical properties, Tara gum, Water
vapor permeability.
