Difference between thermoplastic and thermosetting resins.

Action of Heat.

Thermoplastic polymers or resins soften on heating.

Thermosetting polymers or resins do not soften on heating. At higher temperature they burn or char.

Difference between thermosets and thermoplastics.

Polymerisation

Thermoplastic polymers are formed by addition polymerisation.

Thermosetting polymers are formed by condensation polymerisation.

Nature

Thermoplastics are moldable.

Thermosetting resins are brittle.

Molecular weight

Thermoplastic polymers have low molecular weight.

Thermosetting polymers have high molecular weight.

Solubility

Thermoplastics are soluble in organic solvents.

Thermosetting polymers are insoluble in organic solvents.

Reshaping

Thermoplastic polymers can be softened and reshaped.

Thermosetting polymers cannot be softened and reshaped again.

Example

Polyethylene, polystyrene, PVC etc are thermoplastic polymers.

Phenol formaldehyde, urea formaldehyde, nylon-6,6 etc are thermosetting polymers. Next

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Determination of molecular weight by osmotic pressure method

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Polylactic acid/PLA.

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Polymers

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