Which term describes a plastic that becomes permanently rigid after a curing chemical reaction?

Which term describes a plastic that becomes permanently rigid after a curing chemical reaction?

• A. Thermoplastic
• B. Thermosetting plastic
• C. Elastomer
• D. Composite

Answer: (B)

A plastic that becomes permanently rigid after a curing chemical reaction is a thermosetting plastic. During curing, the polymer chains form strong chemical bonds with each other, creating a three‑dimensional network. This cross‑linked structure locks the material in place, so it won’t melt or become soft if it’s heated again. That makes it rigid and heat resistant even after curing. In contrast, thermoplastics soften when heated and can be reshaped, elastomers remain stretchy and elastic, and composites are created by combining materials (like fibers in a resin) where rigidity depends on the chosen components rather than just a curing step.

A plastic that becomes permanently rigid after a curing chemical reaction is a thermosetting plastic. During curing, the polymer chains form strong chemical bonds with each other, creating a three‑dimensional network. This cross‑linked structure locks the material in place, so it won’t melt or become soft if it’s heated again. That makes it rigid and heat resistant even after curing. In contrast, thermoplastics soften when heated and can be reshaped, elastomers remain stretchy and elastic, and composites are created by combining materials (like fibers in a resin) where rigidity depends on the chosen components rather than just a curing step.