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Why Wool is Warm to Wear- Heat of Sorption
It is expressed in joules per gram ( of dry material)
As we can see from the figures above, wool has the highest heat of sorption. And this heat raises the temperature of the wearer which makes the wool feel warmer. In fact “the heat of sorption from a kg of Merino can be equivalent to the output from an electric blanket over eight hours” (Source ).
You can also find some discussion on Heat of Sorption here.
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