ABSTRACT
The properties of polymers are the function of many other parameters, and particularly parameters of crystalline state, and depend in part also on the shape of the article. The lactam based polyamide represents almost always a multicomponent system which is plasticized because it contains, in addition to purposefully added modifiers and additives, also the residues of monomer and water absorbed from the atmosphere or from some other application medium. During heating of a semicrystalline polymer undercooled to a temperature near absolute zero, the growing free energy causes the continuous increase of the amplitude of elastic atom vibrations in both glass-amorphous and crystalline regions. Structural changes in the temperature regions of individual transitions cause the more or less sudden changes in properties of polyamides. The magnitude of property change is proportional to the character and intensity of transition. Solid-state deformation can bring about a large increase in mechanical properties, provided the external deformation causes an efficient orientation of molecular chains.
