Preparation of polypropylene/high‐melt‐strength PP open‐cell foam for oil absorption

Oil spills not only cause significant economic losses; they also harm the environment. In this study, high‐melt‐strength polypropylene (HMSPP) and linear polypropylene (PP) were compounded at different ratios and foamed by supercritical CO 2 at various temperatures and pressures to develop open‐cell foams for oil absorption applications. The experimental results show that adding HMSPP increased the foam expansion ratio and the open‐cell content and that the foam processing window widened with increasing HMSPP content. The oil absorption experiment results show that the amount of oil absorption increased with the foam expansion ratio and that low oil viscosity resulted in high oil absorption. In addition, the amount of oil absorption remained unchanged after 10 cycles of oil absorption experiments. The oil absorption kinetics study shows that the oil absorption process complied with the pseudo‐second‐order law.