Functional Nanocomposites with a Positive Temperature Coefficient of Resistance Based on Carbon Nanotubes Synthesized by Laser Ablation

This study presents the development of high-performance polymer composites designed for operation under extreme conditions. The research aimed to investigate the influence of laser ablation parameters on the synthesis of carbon nanotubes (CNTs) and to evaluate their efficacy as electrically conductive fillers. CNTs were synthesized using a 200 W laser ablation setup, with the graphite-to-ferrocene ratio in the target varied from 3:1 to 8:1 at a constant pulse duration of 0.1 s. Comprehensive analysis by Raman spectroscopy and scanning electron microscopy (SEM) demonstrated that this method enables the production of nanotubes with controlled morphology and diameters ranging from 20 to 70 nm. It was established that varying the target composition serves as an effective tool for managing the specific surface area and structure of the synthesized CNTs. The obtained nanotubes exhibited high efficiency in forming conductive networks within polymer matrices (exemplified by silicone), thereby imparting the composites with tailored electrophysical properties. A key finding of the work is the identified dependence of the positive temperature coefficient of resistance (PTCR) of the composites on the morphology and composition of the carbon filler. This property opens prospects for creating “smart” self-regulating heating elements based on the developed materials, including for anti-icing systems. Thus, the study results confirm that the targeted synthesis of CNTs via laser ablation and their subsequent incorporation into polymer matrices constitutes an effective strategy for expanding the functional capabilities of composite materials in modern technical applications.