The poly(ethylene 2,6-naphthalate) (PEN)/polycarbonate (PC) blends with the weight ratio
of homopolymers 50/50 wt./wt. were prepared by injection molding using the Engel
machine ES. One mixture was synthesized without the compatibilizer and the second with
the compatibilizer SMAC (Samarium acetylacetonate hydrate). The influence of the compatibilizer
on the physical and mechanical properties of the PEN/PC blends was investigated.
The thermal properties of the new synthesized blends were studied by the
differential scanning calorimetry (DSC). The molecular dynamics of the polymer blends
was studied by the off-resonance NMR. The correlation times of the internal motions
and the spectral density function amplitudes were estimated on the basis of the dispersion
of the spin–lattice relaxation time Toff
1q in the rotating frame off-resonance. The rheological
properties of the studied blends were investigated by dynamic mechanical thermal analysis
(DMTA). The temperature dependencies of the storage modulus G0
, of the loss modulus
G00 and of the loss tangent (tand) were analyzed in order to evaluate the relaxation processes
in the studied systems. The analysis of the DMTA data revealed the existence of
two primary (a1 and a2) and two secondary (b and c) relaxation processes in the blend
of PEN/PC 50/50 wt./wt. and one primary (a) and two secondary (b and c) relaxation processes
in the blend of PEN/PC 50/50 wt./wt. with the compatibilizer. The motional parameters
for the above – mentioned relaxation processes were calculated using the Havriliak–
Negami formalism. The comparative analysis of the DSC, NMR off-resonance and DMTA
results led to the clarification of the molecular motion in the PEN/PC 50/50 wt./wt. blends.