Abstract This work investigated the influence of microcrystalline cellulose (MCC) in thermoplastic starch/poly (butylene adipate-co-terephthalate) films produced by blown extrusion, using different MCC contents (4, 7 and 10 g.100 g-1). The films were characterised for their mechanical, structural and barrier properties. Increasing fibres concentration reduced the tensile strength (6.9 to 4.6 MPa), the elongation at break (568 to 147%) and weight loss in water (12.8 to 11.1%) of the films. The rigidity of the films increased from 19.8 MPa (without MCC) to 79.2 MPa in the samples with 10 g.100 g-1 of MCC. SEM images showed the occurrence of some agglomerates in this sample. The water vapour permeability of the films was not affected by the presence of MCC. The production of starch/PBAT/MCC films by blown extrusion was successful; however some adjustments are necessary to improve the dispersion of the particles at the polymeric matrix.

<title>Resumo</title><p>Foram produzidos 12 laminados com diferentes proporções de amido de mandioca, poli(vinil álcool) (PVA) e glicerol por extrusão usando um planejamento de mistura. A opacidade dos materiais variou entre 31 e 56%, e a concentração de PVA e a interação entre as concentrações de amido e PVA foram os principais responsáveis pelo aumento da opacidade. A diferença de cor (ΔE*) variou entre 20-30, sendo a concentração de amido o principal responsável pelo aumento da diferença de cor, por promover uma coloração mais amarelada nos laminados.</p>

<title>Abstract</title><p>Twelve sheets were produced by extrusion with different proportions of cassava starch, poly (vinyl alcohol) (PVA) and glycerol using a mixture design. The opacity of the materials ranged from 31 to 56%, and the concentration of PVA and the interaction between starch and PVA concentrations the mainly responsible for increasing opacity. The color difference (ΔE*) ranged from 20 to 30, the concentration of starch being primarily responsible for increasing in color difference by promoting a more yellowish color in sheets.</p>