Effect of IR heating and the annealing time on the optical transmittance of polystyrene/Na-Alginate polymer composite films

Composite films of Na-Alginate (Alg) and Polystyrene (PS), which have different glass transition temperatures (T_g), with different weight ratios were prepared. Characterization of the film formation process was carried out by using the photon transmission (PT) measurements and the scanning electron microscopy (SEM) imaging. The composite films were annealed in the standard oven and under the IR lamp (IRH) for comparison. It was observed that IRH speeds up the film formation and decreases the required energy for film formation. On the other hand, the healing energies calculated for the films annealed in IRH were higher than those of the films annealed in the oven. In addition, it was shown that the optical transmittance of the films annealed in IRH increases as the annealing time increases while it is almost constant for the films annealed in the oven. Finally, it was observed that IRH causes some deformations on the surface of the composite films, especially at high temperatures, which may be due to the decomposition of low-T_g Alg polymers.