Investigations of Thermal, Mechanical, and Gas Barrier Properties of PA11-SiO₂ Nanocomposites for Flexible Riser...

Acidic gas penetration through the internal pressure sheath of a flexible riser tends to cause a corrosive environment in the annulus, reducing the service life of the flexible riser. Nanoparticles can act as gas barriers in the polymer matrix to slow down the gas permeation. Herein, we prepared PA11/SiO₂ composites by the melt blending method. The effect of adding different amounts of SiO₂ to PA11 on its gas barrier properties was investigated by conducting CO₂ permeation tests between 20 °C and 90 °C. As the temperature increased, the lowest value of the permeability coefficient that could be achieved for the PA11 with different contents of SiO₂ increased. The composites PA/0.5% SiO₂ and PA/1.5% SiO₂ had the lowest permeation coefficients in the glassy state (20 °C) and rubbery state (≥50 °C). We believe that this easy-to-produce industrial PA/SiO₂ composite can be used to develop high-performance flexible riser barrier layers. It is crucial for understanding riser permeation behavior and enhancing barrier qualities.