Rheology of Self-Healing Polymers

Self-healing polymers rely on reversible physical interactions or dynamic chemical bonds that can reform after damage. However, the relationships between molecular dynamics, viscoelasticity, damage, and healing efficiency are still not fully understood.

The central objective of this PhD project will be to use rheology as a powerful investigative tool to uncover the mechanisms governing self-healing and to establish quantitative relationships between:

• Molecular architecture and reversible interactions;
• Relaxation dynamics and bond-exchange kinetics;
• Damage history and material recovery;
• Rheological healing and restoration of mechanical properties;
• Processing conditions, structure, and long-term performance.

The research may involve:

• Preparation and characterization of self-healing polymers, gels, or dynamic polymer networks;
• Linear and nonlinear viscoelastic characterization;
• Stress relaxation, creep, recovery, and time–temperature superposition;
• Development of original rheological protocols to quantify damage and healing;
• Investigation of the effects of temperature, deformation, waiting time, and repeated damage;
• Correlation of rheological recovery with mechanical healing efficiency;
• Modelling of molecular relaxation, reversible interactions, and healing kinetics.

The project will combine fundamental polymer physics, advanced rheology, materials design, and modelling.

Potential applications

Self-healing polymers are emerging as a new generation of resilient and sustainable materials, with potential applications in:

• Aerospace and automotive structures, where repairing microcracks could improve safety and extend component lifetimes;
• Protective coatings and anticorrosion systems capable of recovering after scratches or impacts;
• Flexible and wearable electronics, including stretchable sensors and conductive materials;
• Soft robotics and artificial muscles, where materials must withstand repeated deformation;
• Biomedical materials, such as injectable hydrogels, tissue-engineering scaffolds, wound dressings, and drug-delivery systems;
• Adhesives, sealants, and membranes exposed to repeated mechanical or environmental damage;
• Additive manufacturing, enabling the fabrication of complex, repairable, and adaptive structures;
• Recyclable and reprocessable thermosets, supporting the development of more sustainable polymer technologies.

By understanding the rheological foundations of healing, this project aims to contribute to the development of materials that are not only high-performing, but also longer-lasting, safer, adaptable, and more sustainable.

http://polymerETS.etsmtl.ca

Applicants should have:

• A master’s degree in chemical engineering, materials engineering, polymer science, chemistry, physics, mechanical engineering, or a related field;
• A strong interest in rheology, polymer physics, and self-healing materials;
• Experience in rheology, polymer characterization, polymer synthesis, mechanics, or modelling;
• An interest in connecting molecular mechanisms to macroscopic material behaviour;
• Good written and oral communication skills in English;
• Curiosity, scientific creativity, and the ability to work both independently and collaboratively.

Knowledge of French is an asset but is not required.