Question
Distinguish between thermosetting and thermoplastic resins. Write example of both the classes.
✓
Answer
| Thermosetting resin | Thermoplastic resin |
| (1) They harden when heated. Once hardened it no longer melts. | (1) They soften when heated and harden again when cooled. |
| (2) They cannot be re-shaped. | (2) They can be reshaped |
| (3) They are strong, hard. | (3) They are weak, soft. |
| (4) Thermosetting resin show cross-linking. Examples : Melamine resin Epoxy resins, Bake-lite. | (4) Thermoplastic molecules do not cross link, hence are flexible. Examples : Polythene, polypropylene, nylon, polyester. |
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