Compositions of thermoplastic starch (TPS) reinforced by high surface area materials were produced, intending to study the variation in polymer properties, focusing on the permeability to water vapor. Colloidal silica (surface area 122.7 m²/g) and a ZSM-5 zeolite (surface area 261.3 m²/g) were used, in loadings from 2 to 10% weight. The results demonstrated that the addition of both materials was favorable to the TPS mechanical properties, however in higher loadings the quality of polymer interfaces and these properties were negatively affected, especially for ZSM-5. In all the cases the inorganic particles reduced the permeability to water vapor in levels below 20% when compared to pure TPS, although the best dispersion of colloidal silica determined better reductions, despite its lower surface area.
Composite; thermoplastic starch; TPS; ZSM-5; zeolite; colloidal silica
