Which type of plastics can be reshaped by repeatedly heating and softening?

Thermoplastics are the type of plastics that can be reshaped by repeatedly heating and softening. This behavior is due to the molecular structure of thermoplastics, which consist of long, linear chains of polymers that can slide past one another when heated. As a result, when thermoplastics are exposed to high temperatures, they become soft and pliable, allowing them to be molded or shaped. Once they cool down, they can solidify into a new form. This process can be repeated multiple times, making thermoplastics versatile and favorable for various applications in manufacturing and repair.

In contrast, thermosetting plastics undergo a chemical change during their curing process, which means that once they are set, they cannot be remolded or reshaped. Composite materials are composed of two or more different materials that combine to create a new set of properties but do not exhibit the reshaping characteristic of thermoplastics. Thermoactive is not a commonly used term in the context of plastics and does not refer to a recognized category of polymers relevant to this question. Thus, thermoplastics effectively stand out as the only type capable of being reshaped with heat, confirming the choice as correct.