Temperature dependence of structural parameters of thin films of polystyrene—fullerene С<sub>60</sub>/С<sub>70</sub> nanocomposite according to neutron reflectometry data

The temperature dependences of the structural parameters of thin films of polystyrene–fullerene C60/C70nanocomposites with a low content of nanoparticles in the vicinity of the glass transition temperature of the polymer matrix were studied by specular neutron reflectometry in the range 15–150°C. The obtained temperature dependences of film thickness were used to estimate the glass transition temperature of film composites. In the case of films with C60fullerene, the dependence had a standard form. The glass transition temperature of the composite film was found to decrease compared to the known value for the pure bulk polymer. In the case of films with C70fullerene, upon transition to high temperatures, a non-monotonic dependence of the film thickness was observed, which hindered the application of the general approach.