Q4 of 29 Page 162

Give scientific explanation

The particles of powder are given an electric charge while spraying themto form the powder coating.

The particles of the powder are given an electrostatic charge due to which a uniform layer of the powder sticks to the metal surface. Then the object is heated in the over along with the coating. A chemical reaction occurs in the layer, resulting in the formation of long cross-linked polymeric chains. This powder coating is highly durable, hard and attractive.


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