High-elastic properties of gels

Elastic properties, chareicteristic for an isotropic solid polymer body, are a specific feature of gels. There exist and find practical use anisotropic gels resembling the structure of liquid crystals, but this subsection will disetiss isotropic gels only. 

Under external forces, a solid body is deformed, i.e. changes its shape and/or volume. The location of every point of the body is defined by a rsidius-vcctor r with its components X = X, X2= y, X3 = 

As a result of deformation, the radius-vector takes some value f, so that 

The quantity w is called a deformation vector (or a shift vector). I he specifying of this vector as a function of x, defines the body deformation completely. In the general ca.se, deformation is characterized by a deformation tensor with its components (in the case of small deformations) 

Phase equUibrium in crosslinked polymer + LMWL system 

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