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Polymers — Chemistry STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 ScienceChemistryPolymers3 Marks
Question
Differentiate between thermoplastic and thermosetting polymers. Give one example of each.
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Answer

Thermoplastic polymers:- These are the linear or slightly branched long chain molecules capable of repeatedly softening on heating and hardening on cooling. Some common examples are polythene, polystyrene, polyvinylchloride.
Thermosetting polymers:- These polymers are cross-linked or heavily branched molecules, which on heating undergo extensive cross-linking in moulds and again become infusible.These cannot be reused. Some common examples are bakelite, urea-formaldehyde resins.

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