What characteristic is typical of thermosetting plastics regarding their melting point?

Thermosetting plastics are characterized by their ability to undergo a chemical change when they are cured or set, which transforms them into a rigid structure. This process involves forming a cross-linked network of polymer chains, making them much more thermally stable compared to thermoplastics. As a result, thermosetting plastics do not melt in the same way as other materials. Instead of having a distinct melting point, they will decompose at high temperatures rather than melt and flow.

The high thermal resistance of thermosetting plastics makes them suitable for applications where heat resistance is critical, such as in electrical insulation and structural components. Their properties allow them to maintain shape and integrity under continuous heat exposure, further emphasizing their classification based on high melting point characteristics.

Therefore, the choice that highlights a high melting point aligns perfectly with the fundamental nature of thermosetting plastics and their behavior under heat.