Cellular Polymers.

Cellular materials widely occur in nature such as wood, cork, corals, sponge, human bones etc.
These natural materials with cellular structure have been used for centuries.
The idea of developing and manufacturing the broad range of cellular polymers arose when these natural cellular structures exhibited excellent properties such as high strength of wood, cushioning properties of cork and straw and good insulating properties of cork and balsa.

Example of cellular polymers.
The multifunctional cellular materials are widely used structurally for cushioning, thermal insulation, energy absorption from impacts, sound absorption and vibration dampening.
The cellular polymers consist of two phase i.e solid and gas.
Cellular rubbers are cellular polymer consisting rubber matrix containing a mass of cells.
Some properties of cellular rubbers are;

1) Limited water absorption.
2) Weather resistant.
3) Resistant to chemical and acid.

Cellular rubbers are used for sealing, isolating and shock absorption etc.
Cellular polymers not only provide insulation but are usually stronger than solid polymers.
10% of plastic resins used nowadays are used for production of cellular polymers.

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Polymers

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