Morphological Study and Dielectric Behavior of Nonisothermally Crystallized Poly(ethylene naphthalate)‎ Nanocomposites as a Function of Graphene Content

الملخص EN

Morphological evolution and dielectric properties of poly(ethylene naphthalate)- (PEN-) graphene nanocomposites nonisothermally crystallized have been investigated.

PEN-graphene nanocomposites containing 0.01, 0.025, 0.05, 0.075, and 0.1 wt% of graphene were prepared by melt blending in a mini twin screw extruder.

The results showed that graphene exhibited a superior influence on morphological and conformational structure of PEN during nonisothermal crystallization at low graphene contents.

Crystallization temperature ( T c ) was found to be increased up to 18°C supporting the high nucleating activity of graphene layers.

Wide angle X-ray diffraction (WAXD) and Fourier Transform Infrared Spectroscopy (FTIR) indicated that graphene modifies the conformation of PEN chains promoting crystallinity and favoring the evolution from α to β crystalline form with homogeneous lamellar thickness.

It may be attributed to the structural similarity between naphthalene rings and graphene structure and to π - π interactions during nucleation.

Dielectric behavior was found to be a function of graphene content where the nanocomposites changed from dielectric to low conducting material when passing from 0.075 to 0.1 wt% of graphene content.

This phenomenon permits having a wide range of properties to fit a wide variety of applications required to store electrical energy of low voltage.