Investigation of mechanical and thermal properties of oriented polyamid copolymer

One of the important processing technologies is the vacuum forming. Complex deformation occurs in this process, and it influences the structure of the material. It is especially important in the case of crystalline polymers as the crystallisation usually occurs in oriented samples. Our research was carried out on vacuum formed PEBAX materials. Mechanical and thermal properties were determined as function of the orientation of the samples. We determined the crystallisation kinetics of the material in isothermal and in non isothermal conditions. It was found that the change of the modulus and the yield stress with the orientation is more or less follows the Hennig-rule. Thermodynamic melting point was determined by Hoffman-Weeks method. It was found that the Avrami-equation can describe the isothermal crystallisation kinetics in very wide range.