The Continuum Mechanics of Solid Polymers

The field of continuum mechanics treats the response of continuous bodies to externally applied forces. Molecular structure is disregarded and the body is pictured as a continuum without gaps or empty spaces. These external forces can deform the body and set it into motion. The motion of a rigid body depends only on its mass and mass distribution, not on its composition. The deformation of the body, however, depends upon its internal constitution and is characterized by “constitutive equations” or “rheological equations of state.” These equations describe the relation between the stress and strain of the material.