Muhammad Asif Abrar | ALES Graduate Seminar

Event details: A graduate exam seminar is a presentation of the student’s final research project for their degree.
This is an ALES MSc Final Exam Seminar by Muhammad Asif Abrar. This seminar is open to the general public to attend.

Zoom Link: https://ualberta-ca.zoom.us/j/98252737100?pwd=65DG2pP34kJWlbpdjhKZlpv4IQeO0Z.1

MSc with Dr. Aman Ullah.

Thesis Topic: Development of Chitosan-Based Films with Enhanced Thermal and Mechanical Properties for Food Packaging Applications

Abstract:

The widespread use of traditional synthetic plastics has led to significant environmental concerns, necessitating the exploration of sustainable alternatives. This growing demand for sustainable and biodegradable materials has brought significant attention to chitosan-based films for eco-friendly applications. However, pure chitosan films have inherent limitations, such as brittleness and poor thermal stability, restricting their practical use for various applications. This study aims to address these challenges by modifying chitosan films using plasticizers (glycerol 15%, sorbitol 10%, and epoxidized canola oil (ECO) 15%) and cross-linkers (citric acid (CA), aspartic acid (AA), and 1,2,3-propane tricarboxylic acid (PTCA)) to enhance their thermal and mechanical properties.

The films were prepared by incorporating optimal plasticizer concentrations and crosslinkers, followed by characterization through Fourier Transform Infrared Spectroscopy (FTIR), Thermogravimetric Analysis (TGA), Differential Scanning Calorimetry (DSC), and tensile strength tests. FTIR spectra confirmed successful interactions between chitosan, plasticizers, and cross-linkers, with characteristic shifts in O–H, N–H, and C=O bands. TGA results showed that cross-linking, particularly with PTCA and CA, significantly improved thermal stability, delaying the onset degradation temperature and reducing weight loss. DSC analysis revealed that glycerol enhanced chain mobility and reduced the melting point, while cross-linkers like PTCA restricted molecular motion, improving thermal stability. Tensile strength tests demonstrated that glycerolplasticized films exhibited the highest flexibility (strain ~25%), while CA-cross-linked films achieved superior mechanical strength (~55 MPa) due to strong ester bond formation.

In conclusion, combining plasticizers and cross-linkers has an effective impact on the thermal, mechanical, and structural properties of chitosan films. The formulation of glycerol 15% with CA 5% exhibited the most balanced and superior performance, making it suitable for sustainable food packaging applications. This study highlights the potential of modified chitosanbased films as eco-friendly alternatives to synthetic food packaging materials, with opportunities for future optimization and large-scale production.