Intrinsic Deformation Behavior of Semicrystalline Polymers

Electromechanical instability in semicrystalline polymers

When a layer of a semicrystalline polymer is subject to a tensile force in its plane and a voltage through its thickness, the deformation of the layer is initially homogeneous, but it then localizes. The electromechanical instability sets in when the force and the voltage reach critical conditions. The critical conditions are determined in this paper and are related to the following two special...

Enthalpy recovery in semicrystalline polymers

Constitutive equations are derived for enthalpy recovery in polymeric glasses after thermal jumps. The model is based on the theory of cooperative relaxation in a version of the trapping concept. It is demonstrated that some critical temperature Tcr and some critical degree of crystallinity fcr exist in a semicrystalline polymer above which the energy landscape becomes homogeneous and structura...

A “Layered Look” for Spherical Nanoparticles in Semicrystalline Polymers

In 1993, researchers at Toyota Central R&D reported that 5 wt % of an exfoliated clay could double the roomtemperature modulus of nylon-6, a semicrystalline engineering plastic, and raise its heat distortion temperature by more than 80 °Call without sacrificing toughness. That work stimulated a worldwide effort to synthesize and study polymer–matrix nanocompositesand it also highlighted the i...

Restricted dynamics in oriented semicrystalline polymers: poly(vinilydene fluoride).

The effect of confinement by crystals on the α relaxation, observed by dielectric broadband spectroscopy, in isotropic as well as in oriented semicrystalline poly(vinilydene fluoride), is analyzed on the basis of a new thermodynamic model. In both samples, it has been found that the average free-energy barrier, ΔF, for conformational rearrangements is of the same order of the dispersion barrier...

Electric field-induced deformation of polydimethylsiloxane polymers