Why rubbers are incompressible

[Amol]

Dear All,

I have very basic question. Why rubbers are incompressible?

I am not expecting answers like it's poisson's ratio is 0.5 or bulk modulus is infinite.

Please forgive me if i am asking a sily question.

Amol

[Jorgen]

That is not a silly question. I would say, however, that rubbers are not incompressible. That is, they have a finite compressibility, and a finite bulk modulus.

The reason they are almost incompressible for many modeling purposes is that the shear modulus is so low compared to the bulk modulus that the actual value that is chosen for the bulk modulus does not matter much.

-Jorgen

[Amol]

Thanks Dr. Jorgan,

I am actually keen to know what is that at microscopic level makes rubber behave in incompressible manner.

best regards
Amol

[manfred]

Thanks Dr. Jorgan,

I am actually keen to know what is that at microscopic level makes rubber behave in incompressible manner.

best regards
Amol

...rubbers are incompressible because the assembly of chain molecules from which rubbers are build up repels each other and thus resits to be compressed when external forces are applied.

[Amol]

Thanks Dr. Jorgon and Mr. manfred for your inputs.

regards
Amol