Used primarily as a stable free radical in chemical research, it serves as a standard for calibrating electron paramagnetic resonance (EPR) spectroscopy. Its stability and distinct EPR signal make it valuable for studying free radical reactions and mechanisms. Additionally, it is employed in polymer chemistry to monitor the aging and degradation of materials by tracking radical formation. In antioxidant research, it helps assess the radical scavenging activity of various compounds. Its applications also extend to the development of new materials and the study of oxidative stress in biological systems.