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Question
Distinguish between
Thermoplastic and thermosetting plastic.
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Solution
| Thermoplastic polymers | Thermosetting polymers |
| These are formed by addition polymerisation | These are formed by condensation polymerization |
| Generally more expensive than thermosetting | Cost-effective |
| Monomer used in these is generally bifunctional | In this monomer used is tri, tetra or polyfunctional |
| Aesthetically-superior finishes | More difficult to surface finish |
| They are long-chain linear polymer with negligible cross-links | These have three-dimensional network structure with number of cross-links |
| less resistant to high temperatures | More resistant to high temperatures than thermoplastics |
| They have low molecular wt. | They have high molecular wt. |
| They are soft, weak, brittle | They are hard, strong and more brittle |
| Highly recyclable | Cannot be recycled |
| They can be softened and reshaped and reused. | They cannot be softened and reshaped again once again. Highly flexible design |
| High-impact resistance | Low-impact resistance |
| Remoulding/reshaping capabilities | Cannot be remoulded or reshaped |
| Eco-friendly manufacturing | Eco-foe manufacturing |
| e.g.- polyethene, polystyrene, PVC, PVA etc. | e.g.- phenol-formaldehyde, ureaformaldehyde, nylon 6 : 6 etc. |
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