Microstructural imaging and characterization of the mechanical, chemical, thermal, and swelling properties of starch–chitosan blend films

Chitosan has wide range of applications as a biomaterial, but barriers still exist to its broader use due to its physical and chemical limitations. The present study evaluated the properties of the polymeric blend films obtained from chitosan and potato starch by the casting/solvent evaporation method. The swelling properties of the different films studied as a function of pH showed that the sorption ability of the blend films increased with the increasing content of starch. Fourier transform infrared (FTIR) analyses confirmed that interactions were present between the hydroxyl groups of starch and the amino groups of chitosan in the blend films while the x‐ray diffraction (XRD) studies revealed the films to exhibit an amorphous character. Thermogravimetric analyses showed that in the blend films, the thermal stability increased with the increasing starch content and the stability of starch and chitosan powders reduced when they were converted to film. The differential scanning calorimetry (DSC) studies revealed an endotherm corresponding to water evaporation around 100°C in all the films and an exotherm, corresponding to the decomposition in the chitosan and blend films. Scanning electron microscopy (SEM) observations indicated that the blend films were less homogenous and atomic force microscopy (AFM) studies revealed the chitosan films to be smooth and homogenous, while the starch films revealed characteristic granular pattern. The blend films exhibited an intermediate character with a slight microphase separation. The starch–chitosan blend films exhibited a higher flexibility and incorporation of potato starch into chitosan films improved the percentage elongation. © 2006 Wiley Periodicals, Inc. Biopolymers 82: 176–187, 2006

[1]  T. Kissel,et al.  The depolymerization of chitosan: effects on physicochemical and biological properties. , 2004, International journal of pharmaceutics.

[2]  K. Kurita,et al.  Studies on chitin: 7. I.r. spectroscopic determination of degree of deacetylation , 1978 .

[3]  J. Bemiller,et al.  Methods in Carbohydrate Chemistry , 1965 .

[4]  Lina Zhang,et al.  Structure and properties of casting films blended with starch and waterborne polyurethane , 2001 .

[5]  C. Mercier Formation of amylose-lipid complexes by twin-screw extrusion cooking of manioc starch , 1980 .

[6]  J. M. Bunn,et al.  Mechanical and barrier properties of edible chitosan films as affected by composition and storage , 1996 .

[7]  Seon Jeong Kim,et al.  Synthesis and characteristics of interpenetrating polymer network hydrogel composed of chitosan and poly(acrylic acid) , 1999 .

[8]  J. Swanston,et al.  Starch production and industrial use , 1998 .

[9]  R. Wool,et al.  Degradation of polyethylene–starch blends in soil , 1991 .

[10]  M. Mucha,et al.  Thermal analysis of chitosan and its blends , 2005 .

[11]  D. Wong,et al.  Chitosan-lipid films: microstructure and surface energy , 1992 .

[12]  A. Zhu,et al.  Preparation and characterization of novel silica-butyrylchitosan hybrid biomaterials* , 2003, Journal of materials science. Materials in medicine.

[13]  E. Gbur,et al.  Comparison of two models to predict amylose concentration in rice flours as determined by spectrophotometric assay , 1991 .

[14]  S. Hulleman,et al.  Formation of starch films with varying crystallinity , 1997 .

[15]  T. Yoshioka,et al.  Encapsulation of mammalian cell with chitosan‐CMC capsule , 1990, Biotechnology and bioengineering.

[16]  Jin Hong Kim,et al.  Properties and swelling characteristics of cross‐linked poly(vinyl alcohol)/chitosan blend membrane , 1992 .

[17]  R. Marchessault,et al.  Infrared spectra of crystalline polysaccharides. V. Chitin , 1960 .

[18]  J. Román,et al.  A kinetic study of the thermal degradation of chitosan and a mercaptan derivative of chitosan , 1993 .

[19]  G. Roberts,et al.  Determination of the viscometric constants for chitosan , 1982 .

[20]  J. Viyoch,et al.  Formulation and development of a patch containing tamarind fruit extract by using the blended chitosan-starch as a rate-controlling matrix. , 2003, International Journal of Cosmetic Science.

[21]  Xupin Zhuang,et al.  Study on antibacterial O-carboxymethylated chitosan/cellulose blend film from LiCl/N, N-dimethylacetamide solution , 2002 .

[22]  J. Arul,et al.  Chitosan Coating Effect on Storability and Quality of Fresh Strawberries , 1991 .

[23]  C. Hill,et al.  The preparation and characterisation of a series of chemically modified potato starches , 2002 .

[24]  S. Gunasekaran,et al.  Selected properties of pH‐sensitive, biodegradable chitosan–poly(vinyl alcohol) hydrogel , 2004 .

[25]  R. Tharanathan,et al.  Properties of chitosan films prepared under different drying conditions , 2004 .

[26]  C. Rose,et al.  Mechanical and microstructure studies on the modification of CA film by blending with PS , 2002 .

[27]  Tianxi Liu,et al.  Biopolymer chitosan/montmorillonite nanocomposites: Preparation and characterization , 2005 .

[28]  E. Styková,et al.  Investigation of the hydrodynamic properties of chitosan solutions , 1985 .

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

[30]  L. Hadwiger,et al.  The fungicidal effect of chitosan on fungi of varying cell wall composition , 1979 .

[31]  R. Simão,et al.  High resolution imaging of the microstructure of maize starch films , 2003 .

[32]  P. Caboni,et al.  Phenylpyrazole insecticide photochemistry, metabolism, and GABAergic action: ethiprole compared with fipronil. , 2003, Journal of agricultural and food chemistry.

[33]  J. Mcginity,et al.  Influence of water soluble and insoluble plasticizers on the physical and mechanical properties of acrylic resin copolymers , 1994 .

[34]  J. Ma,et al.  Properties of polyelectrolyte complex films of chitosan and gelatin , 1999 .

[35]  Hua Zheng,et al.  Preparation and characterization of chitosan/poly(vinyl alcohol) blend fibers , 2001 .

[36]  K. Gupta,et al.  Semi-interpenetrating polymer network beads of crosslinked chitosan–glycine for controlled release of chlorphenramine maleate , 2000 .