Drawn gelatin films with improved mechanical properties

Area of Science:

• Biomaterials Science
• Polymer Science
• Materials Engineering

Background:

• Gelatin films are widely used but often lack mechanical strength and anisotropy.
• Developing methods to improve mechanical properties of gelatin is crucial for advanced applications.

Purpose of the Study:

• To investigate the effect of uniaxial stretching on the mechanical properties and structure of gelatin films.
• To explore the relationship between gelatin strand alignment, renaturation level, and mechanical performance.
• To assess the potential of stretched gelatin as a biomaterial.

Main Methods:

• Uniaxial stretching of gelatin films at constant relative humidity.
• Cross-linking with glutaraldehyde.
• Characterization using mechanical testing, differential scanning calorimetry (DSC), and scanning electron microscopy (SEM).
• Calculation of renaturation level based on melting enthalpy.

Main Results:

• Young's modulus and stress at break increased linearly with draw ratio, reaching up to five times higher values.
• Stretching significantly increased gelatin strand alignment and decreased film thickness.
• Improved mechanical properties correlated strongly with a higher renaturation level (collagen-like structure).

Conclusions:

• Uniaxial stretching is an effective method to create anisotropic gelatin films with significantly enhanced mechanical properties.
• The renaturation level is a key factor in achieving improved mechanical performance in stretched gelatin.
• This technique offers a viable route for preparing advanced biomaterials from gelatin.