Influence of the simultaneous addition of bentonite and cellulose fibers on the mechanical and barrier properties of starch composite-films

The addition of nanoclay or cellulose fibers has been presented in the literature as a suitable alternative for reinforcing starch films. The aim of the present work was to evaluate the effect of the simultaneous incorporation of nanoclay (bentonite) and cellulose fibers on the mechanical and water barrier properties of the resultant composite-films. Films were prepared by casting with 3% in weight of cassava starch, using glycerol as plasticizer (0.30 g per g of starch), cellulose fibers at a concentration of 0.30 g of fibers per g of starch and nanoclay (0.05 g clay per g starch and 0.10 g clay per g starch). The addition of cellulose fibers and nanoclay increased the tensile strength of the films 8.5 times and the Young modulus 24 times but reduced the elongation capacity 14 times. The water barrier properties of the composite-films to which bentonite and cellulose fibers were added were approximately 60% inferior to those of starch films. Diffractograms showed that the nanoclay was intercalated in the polymeric matrix. These results indicate that the simultaneous addition of bentonite and cellulose fibers is a suitable alternative to increase the tensile strength of the films and decrease their water vapor permeabilities.

[1]  J. Kennedy,et al.  Studies on the properties of natural fibers-reinforced thermoplastic starch composites , 2005 .

[2]  M. Grossmann,et al.  Water sorption and mechanical properties of cassava starch films and their relation to plasticizing effect , 2005 .

[3]  J. Smith Moisture Sorption: Practical Aspects of Isotherm Measurement and Use , 1986 .

[4]  P. Dole,et al.  Quaternary starch based blends: Influence of a fourth component addition to the starch/water/glycerol system , 2006 .

[5]  Mohamed Mathlouthi,et al.  Analysis of water binding in starch plasticized films , 2006 .

[6]  H. Bader,et al.  Influence of natural fibres on the mechanical properties of biodegradable polymers. , 1998 .

[7]  W. Bergthaller,et al.  Processing and characterization of biodegradable products based on starch , 1998 .

[8]  J. Laurindo,et al.  Effect of cellulose fibers addition on the mechanical properties and water vapor barrier of starch-based films. , 2009 .

[9]  G. Glenn,et al.  Rheology of starch–clay nanocomposites , 2005 .

[10]  P. Sobral,et al.  Hygroscopicity and water vapor permeability of Kraft paper impregnated with starch acetate , 2005 .

[11]  A. Dufresne,et al.  Improvement of Starch Film Performances Using Cellulose Microfibrils , 1998 .

[12]  F. Wypych,et al.  Starch films reinforced with mineral clay , 2003 .

[13]  K. Réczey,et al.  Reducing water absorption in compostable starch-based plastics , 2005 .

[14]  N. Zaritzky,et al.  Microstructural characterization of plasticized starch-based films , 2000 .

[15]  P. Gatenholm,et al.  Crystallinity and morphology in films of starch, amylose and amylopectin blends. , 2002, Biomacromolecules.

[16]  Won‐Ki Lee,et al.  Environmentally friendly polymer hybrids Part I Mechanical, thermal, and barrier properties of thermoplastic starch/clay nanocomposites , 2003 .

[17]  A. J. Carvalho,et al.  Thermoplastic starch–cellulosic fibers composites: preliminary results , 2001 .

[18]  J. Laurindo,et al.  Evaluation of the effects of glycerol and sorbitol concentration and water activity on the water barrier properties of cassava starch films through a solubility approach , 2008 .

[19]  D. Lourdin,et al.  Influence of equilibrium relative humidity and plasticizer concentration on the water content and glass transition of starch materials , 1997 .

[20]  J. Krochta,et al.  Edible and biodegradable polymer films: challenges and opportunities , 1997 .

[21]  P. Sobral,et al.  Influence of the glycerol concentration on some physical properties of feather keratin films , 2006 .

[22]  N. Gontard,et al.  Water and Glycerol as Plasticizers Affect Mechanical and Water Vapor Barrier Properties of an Edible Wheat Gluten Film , 1993 .

[23]  J F Vliegenthart,et al.  Crystallinity in starch plastics: consequences for material properties. , 1997, Trends in biotechnology.

[24]  K. S. Miller,et al.  Oxygen and aroma barrier properties of edible films: A review , 1997 .

[25]  Stéphane Guilbert,et al.  Reinforcement of plasticized wheat gluten with natural fibers : From mechanical improvement to deplasticizing effect , 2008 .

[26]  Jochen Weiss,et al.  Functional Materials in Food Nanotechnology , 2006 .

[27]  E. Chiellini,et al.  Characterization of Biodegradable Composite Films Prepared from Blends of Poly(Vinyl Alcohol), Cornstarch, and Lignocellulosic Fiber , 2005 .

[28]  Theodore P. Labuza,et al.  Moisture Sorption: Practical Aspects of Isotherm Measurement and Use , 2000 .

[29]  L. Avérous,et al.  Plasticized starch–cellulose interactions in polysaccharide composites , 2001 .

[30]  Long Yu,et al.  Polymer blends and composites from renewable resources , 2006 .

[31]  A. Vázquez,et al.  Physical and mechanical properties of thermoplastic starch/montmorillonite nanocomposite films , 2008 .

[32]  Chan-Young Park,et al.  Preparation and Properties of Biodegradable Thermoplastic Starch/Clay Hybrids , 2002 .

[33]  J. Laurindo,et al.  Mechanical and barrier properties of composite films based on rice flour and cellulose fibers , 2011 .