Study of some Complex Organic Materials Characteristics in Thin Films

Studies were carried out in order to investigate the sensitivity of some thin films, to ultraviolet light, based on barium stearate and carbon nanotubes structures. A three – five monolayers structures were developed using the Langmuir – Blodgett technique onto ceramic substrate. Obtained Langmuir – Blodgett complex thin films shows sensitivity to ultra violet light radiation, taking into consideration the presence of carbon nanotubes that facilitates the charge carriers transport. Also the investigations performed, revealed the properties of carbon nanotubes and point out the fine chemistry of these materials. Based on this premise we proceed to investigate and characterize the photo – electrical behavior of the obtained structures.

Effect of Barium Stearate on the Thermal Stability of Polyvinyl Chloride

Thermal degradation reaction kinetics of PVC stabilized by barium stearate were studied by means of the non-isothermal weight-loss technique under a nitrogen atmosphere. The results show that the lowest decomposition temperature is greater than 203.6°C and 217.2°C in the conversion rate of 5% and 10% respectively. When the heating rate β is 10°C/min, at 200°C and 225°C the remaining mass from the sample with barium stearate was 99.1% and 95.3%, respectively. The thermal decomposition process occurred in three stages, the results calculated by various methods show that the average apparent activation energy in first, second and third phase is 79.88kJ/mol, 89.37kJ/mol and 187.34kJ/mol respectively. In the initial reaction ( α<18%), as heating rate is 20°C/min, the decomposition reaction is controlled by the (A1.5) mechanism.