Ketjenblack-Reinforced Chloroprene Rubber / Brominated Butyl Rubber Blends: Enhanced Ozone and UV Stability, Air Permeability, and Tribological Performance

• • Optimal KB loading is 10 phr, yielding maximum tensile strength at room temperature and best tribological and barrier performance due to uniform filler dispersion, critical for components requiring wear resistance and low gas permeability. • • Tensile strength retention exceeds 80% for all compositions after aging in ozone, UV, and saline environments, indicating robust durability for outdoor or chemically aggressive service conditions. • • The 20% KB composite exhibits a 5 °C reduction in glass transition temperature (Tg), extending the operational temperature range for rubber-like elasticity, beneficial for applications in variable climates. • • Activation energy for thermal decomposition, determined via KAS modeling, is highest for the KB20 composite, signifying enhanced thermal stability and resistance to high-temperature degradation.