Epoxy based materials are an important group of materials as they are used in many industrial fields due to their good mechanical, thermal and chemical properties. In the modern world, the recyclability and the ability of long-term use are becoming more and more desirable properties of materials. Self-healing is the ability of the material that after injury, fully or at least partially restore its properties to the original state and thus prolongs the lifespan. Self-healing of polymeric materials can be in general divided into physical self-healing, where physical entanglements with chains occur and chemical self-healing, where new bonds are formed. To study the effect of solvent on the self-healing of epoxy material in my master's thesis, I first prepared epoxy matrices without and with Diels-Alder components, using the solvent according to known procedures. Furthermore, I successfully adapted the preparation of epoxy matrices by excluding the use of a solvent from all steps of the process, thus obtaining an epoxy matrix without and with Diels-Alder components without the presence of a solvent. Using dynamic mechanical analysis, I compared the mechanical properties, crosslinking and the temperature of the glass transition of prepared materials. As expected, I found that the presence of a solvent reduces the degree of crosslinking and thus lowers the glass transition temperature. The solvent's effect on the efficiency of self-healing was determined with the help of tensile tests by fracture toughness. I first damaged each of the materials and then cured them at different temperature programs which are corresponding to chemical self-healing, based on the reversible Diels-Alder reaction, and physical self-healing, above the glass transition temperature. In general, the presence of a solvent improved the healing efficiency of both temperature programs.
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