Molecular interactions in gelatin/chitosan composite films

Area of Science:

• Biomaterials Science
• Polymer Chemistry
• Materials Engineering

Background:

• Gelatin and chitosan are biocompatible polymers with potential applications in various fields.
• Understanding their interactions is crucial for developing novel composite materials.

Purpose of the Study:

• To investigate the rheological properties of gelatin-chitosan solutions and films.
• To elucidate the molecular interactions between gelatin and chitosan.
• To assess the miscibility and thermal properties of gelatin-chitosan blends.

Main Methods:

• Preparation of gelatin-chitosan solutions at varying mass ratios.
• Rheological measurements (storage modulus) of solutions during cooling.
• Analysis of molecular interactions using FTIR spectroscopy (amide-II band shifts).
• Characterization of composite films using X-ray diffraction and differential scanning calorimetry (DSC) for glass transition temperature (Tg).

Main Results:

• Gelatin-chitosan interactions increased the storage modulus of gelatin solutions due to complex formation.
• These interactions hindered gelatin network formation, decreasing the storage modulus of polymer gels.
• Hydrogen bonds and electrostatic interactions were confirmed between gelatin and chitosan.
• Triple helix content in composite films decreased with increasing chitosan.
• A single, composition-dependent glass transition temperature (Tg) indicated good miscibility and blend formation.

Conclusions:

• Gelatin and chitosan form complexes through hydrogen bonding and electrostatic interactions.
• The rheological and thermal properties of the blends are significantly influenced by these interactions.
• Gelatin and chitosan exhibit good miscibility, forming a wide range of blends suitable for various applications.