Glass transition facts for kids

The glass transition is the transition of amorphous solids from a hard and brittle state into a molten or rubber-like state. An amorphous solid that goes through a glass transition is called a glass. Supercooling a viscous liquid into the glass state is called vitrification.

The glass transition temperature T_g is always lower than the melting temperature, T_m, of the crystalline state of the material, if one exists. Above a glass transition temperature, a plastic is rubbery. Below the glass transition temperature, a plastic is solid. Thermosets, or thermo-setting plastics, burn up before they reach their melt temperature, but most thermosets also undergo glass transition.

Images for kids

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  Determination of Tg by dilatometry.

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  Entropy difference between crystal and undercooled melt

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  In ironing, a fabric is heated through the glass-rubber transition.

See also

In Spanish: Transición Vítrea para niños