Rheological and thermo-mechanical evaluation of bio-based chitosan/pectin blends with tunable ionic cross-linking

Int J Biol Macromol. 2018 Oct 15;118(Pt B):1817-1823. doi: 10.1016/j.ijbiomac.2018.07.027. Epub 2018 Jul 11.

Abstract

Bio-based chitosan/pectin blend films were prepared by solution casting and fully characterized in terms of their viscoelastic, thermo-mechanical and water affinity properties. Dynamic light scattering and rheological analyses served as a probe that polyelectrolyte complexes were formed through COO-/NH3+ ionic cross-linking, changing the chitosan/pectin solutions from Newtonian to pseudoplastic gel-like systems. The highest degree of ionic cross-linking has been found at a specific mass ratio (chitosan/pectin 25/75) and solid-state data were obtained in detail using dynamic mechanical thermal analysis. Ionic cross-linking was determining on the physical properties of chitosan/pectin blends, which was demonstrated by the thermo-mechanical spectra, high water contact angle and tensile strength of films. The specific thermo-mechanical properties of the chitosan/pectin films can be specifically modulated according to the chitosan/pectin mass ratio to ensure successfully applications in medicine, drug delivery, agricultural and food coatings.

Keywords: Cross-linking; Natural polymers; Synergism; Viscoelastic properties.

MeSH terms

  • Chitosan / chemistry*
  • Dynamic Light Scattering
  • Elasticity
  • Ions / chemistry*
  • Mechanical Phenomena
  • Pectins / chemistry*
  • Polymers / chemistry
  • Rheology
  • Spectroscopy, Fourier Transform Infrared
  • Thermodynamics
  • Viscosity

Substances

  • Ions
  • Polymers
  • Pectins
  • Chitosan