Cassava bagasse as a reinforcement agent in the polymeric blend of biodegradable lms Guilherme Ribeiro de Carvalho, 1 Geovana Silva Marques, 1 Luiz Mario de Matos Jorge, 2 Regina Maria Matos Jorge 1 1 Department of Chemical Engineering, Graduate Program in Chemical Engineering, Federal University of Paraná UFPR, Avenue Coronel Francisco Heráclito dos Santos, S/N, Curitiba, Paraná 81531-980, Brazil 2 Department of Chemical Engineering, Graduate Program in Chemical Engineering, State University of Maringa UEM, Avenue Colombo, 5790, Maringa, Paraná 87020-900, Brazil Correspondence to: R. M. M. Jorge (rjorge@ufpr.br) ABSTRACT: The objective of this work was to develop biodegradable lms using brous residue from the extraction of cassava starch and to investigate its effect as a reinforcement agent in polymeric lms. Micrographs (SEM) showed that the obtained lms presented smooth surfaces with no cracking. The addition of bers affected the properties of the lms signicantly (p < 0.05), reducing water vapor permeability values (from 8.63 0.15 × 10 -11 g.m.m -2 .s -1 .Pa -1 to 3.33 0.16 × 10 -11 g.m.m -2 .s -1 .Pa -1 ) and increasing the maximum tensile strength (from 1.23 0.15 MPa to 7.78 0.83 MPa). These results encourage the use of cassava bagasse as a rein- forcement in the production of green composites as packaging. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 47224. KEYWORDS: green composites; mechanical properties; starch; water vapor permeability Received 19 April 2018; accepted 14 September 2018 DOI: 10.1002/app.47224 INTRODUCTION Synthetic plastics industry is constantly evolving to meet global demands. As a result of this action, the annual production of nonbiodegradable plastics reached 322 million tons in the world in 2015, and plastic food packaging were responsible for 40% of world production. 1 In parallel to the high production of plastics is the high volume of discard of these materials after use. The improper disposal of synthetic plastic packaging from petrochemical origin represents an environmental problem, which is aggravated annually. 2 As a result, researches in the eld of biodegradable polymeric mate- rials and composites have been carried out to preserve the envi- ronment and to improve the quality of developed materials and life in society. 3,4 Among researches in this area, the number of studies that address the application of natural resources in the preparation of materials increases, especially renewable polymer matrices and natural bers. Biodegradable lms are packaging materials produced from renewable and biodegradable sources. They are a promising alter- native to replace, at least in part, conventional synthetic polymers of plastic packaging. 5,6 The functionality and performance of biodegradable lms depend on their mechanical and water vapor permeability (WVP) properties, which in turn depend on the lm composition, forming process, and method of application in the product. 7 Among the renewable possibilities, cassava starch is considered a polymer with high potential to produce biodegradable packaging, because of its low cost and abundance for industrial scale use. In addition, it is biodegradable when released into the environ- ment. 8,9 Despite the benets of this renewable source for the pro- duction of bioplastics, its application in food packaging is still restricted, as inferior physical and barrier properties challenge its implementation. 10 To solve application problems, special treat- ments are required to the lm, such as the addition of vegetable bers and other additives, such as glycerol, to improve mechani- cal, thermal, and water contact properties. 11,12 The use of different compounds in the polymer blend is reported in the literature aiming to give specic properties to the lms produced. Some authors have studied the addition of natural bers, such as luffa ber, 13 kenaf ber, 14 cotton bers, 15 bamboo bers, 16 and rice bark bers, 4 as reinforcing agents. Debiagi et al., 17 used poly(vinyl alcohol) to improve mechanical and water vapor barrier properties, and essential oils as antimicrobial agents in the production of biodegradable trays based on cassava bagasse. Edhirej et al. 18 used different types of plasticizers (fructose, urea, tri-ethylene glycol, and © 2018 Wiley Periodicals, Inc. 47224 (1 of 7) J. APPL. POLYM. SCI. 2018, DOI: 10.1002/APP.47224