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Researchers found that the compound TEMPO can effectively suppress free radical formation and control the dangerous thermal decomposition of TBPB, significantly improving its safety profile during production, storage, and transportation.

TBPB is an organic peroxide commonly employed in the synthesis of polymers due to its strong oxidative capabilities. However, the compound contains a peroxide bond that is highly sensitive to heat, shock, and friction, making it prone to decomposition and even explosion under adverse conditions.

While previous research has examined safer synthesis methods and the basic thermodynamic behavior of TBPB, there has been limited insight into controlling its thermal hazard at the molecular level. This knowledge gap poses persistent risks in industrial settings where TBPB is handled in large quantities. Based on these challenges, a deeper understanding and control of TBPB's thermal decomposition are urgently needed.

A study in Emergency Management Science and Technology by Juncheng Jiang and Lei Ni's team, Nanjing Tech University, enhances the thermal safety of TBPB during both routine and high-risk operations.

To evaluate the thermal hazard of TBPB, researchers employed multiple analytical techniques, including differential scanning calorimetry (DSC), kinetic modeling, Fourier transform infrared (FTIR) spectroscopy, and electron paramagnetic resonance (EPR) spectroscopy.

Thermal decomposition behavior was first analyzed by recording DSC heat flow curves across various heating rates, which revealed that TBPB undergoes a strongly exothermic reaction within 100–210 °C, peaking around 150 °C. The heat released during this decomposition averaged 924.59 J/g, indicating significant thermal risk. Kinetic analysis using KAS, FWO, and Starink methods yielded consistent activation energy (E(—)a) values, averaging 97.55 kJ/mol, confirming TBPB's susceptibility to decomposition under moderate heating.

FTIR analysis identified volatile decomposition products including alcohols, aldehydes, aromatic acids, and carbon dioxide, particularly prominent at 160 °C. Concurrently, EPR spectroscopy revealed the formation of two types of alkoxy radicals and one alkyl radical during thermal breakdown at 110 °C.

To address the associated safety concerns, the team introduced TEMPO, a radical scavenger, into the TBPB system. EPR spectra demonstrated that TEMPO effectively suppressed the formation of reactive radicals, while DSC and adiabatic calorimetry confirmed significant reductions in peak exothermic temperatures, heat release, and pressure buildup. Specifically, the adiabatic temperature rise (ΔTad*) was reduced by 43.93 °C, and the total heat release dropped by nearly 25%, alongside a 0.43 MPa decrease in pressure.

These findings establish that TEMPO can efficiently inhibit both free radical generation and thermal runaway of TBPB, offering a viable strategy to enhance the safety of TBPB in industrial polymerization and chemical synthesis operations.

In conclusion, by incorporating TEMPO as a stabilizer, manufacturers can enhance the thermal safety of TBPB during both routine and high-risk operations. This technique can reduce accident risks in chemical plants, improve process reliability, and ensure safer transport of reactive chemicals.

Moreover, the precise mechanisms by which TEMPO suppresses radical propagation offer a promising avenue for developing new classes of inhibitors. As the demand for high-performance initiators grows, ensuring their safety through molecular-level control will be a central focus in chemical process safety research.