In this study, phthalimide derived polymer-TiO2 nanocomposites were prepared
by direct mixing method and their mechanical properties were compared. The
high content filler polymer nanocomposites with sufficient interface bonding
with the polymer matrix have been prepared to maximize the properties of the
filler. In the direct mixing method, the polymer obtained by free radical
polymerization of the monomer was mixed with TiO2 in high weight
percentages. The pulse-echo method was used to characterize the elastic
constants of the polymer and polymer-TiO2 nanocomposites through detection
of the ultrasonic waves. Transverse and longitudinal ultrasonic velocities
have been used to calculate Young?s modulus of these samples. The ultrasonic
velocity and Young?s modulus values of polymer-TiO2 nanocomposites showed a
linear relationship with the weight percentage of the polymer, which is due
to the strong and effective interaction between the particles resulting
from by reinforcing TiO2 to the polymer structure. The clustering that
emerged with the increase in the amount of reinforcement in the SEM images
became more pronounced and it was observed that pure polymer and TiO2 were
homogeneously distributed. The porosity and hardness measurements of the
polymer and polymer-TiO2 nanocomposites were examined. The hardness and
porosity of the polymer structure approximately increased as the percentage
values of TiO2 increased. Moreover, TGA results of polymer nanocomposites
obtained by direct mixing showed that the thermal stability increased
linearly as the weight ratio increase of TiO2 in comparison with the pure
polymer.