Lämpökovetuessaan

Lämpökovetuessaan is a Finnish term that describes a process where a material undergoes irreversible hardening upon heating. This phenomenon is characteristic of thermosetting polymers, also known as thermosets. Unlike thermoplastics, which can be repeatedly melted and reshaped by heating, thermosets undergo a chemical reaction during their initial heating process that creates a permanent, cross-linked molecular structure.

When a thermosetting material is heated, its molecules become more mobile, allowing them to react with each other. This reaction, often initiated by a catalyst or added curing agent, forms strong chemical bonds between the polymer chains. This creates a rigid, three-dimensional network that prevents the material from flowing or deforming when subsequently heated. Once this cross-linking has occurred, the material is permanently hardened and cannot be softened or remelted without degradation.

Examples of materials that exhibit lämpökovetuessaan include epoxy resins, phenolic resins, and vulcanized rubber. This property makes thermosets ideal for applications requiring high thermal stability, mechanical strength, and chemical resistance, such as in electrical insulation, automotive parts, and durable coatings. The irreversible nature of the hardening process means that manufactured thermoset parts cannot be recycled in the same way as thermoplastics.