In Situ High-Efficient Construction of UiO-66@AgNPs Nanocomposite as Heterogeneous Metallocene Catalytic Carrier for Preparing Antibacterial Polypropylene

Antibacterial polypropylene (PP) is of great applied value in the health care and food packaging fields; however, there are many challenges in preparation because of the nonpolar characteristic of PP. Herein, AgNPs as a kind of broad-spectrum antibacterial agent have been innovatively developed via in situ reduction of Ag precursor in the classical metal-organic framework (MOF) carrier, UiO-66. AgNPs in UiO-66 can maintain stability and do not agglomerate. Furthermore, to solve the dispersion problem of AgNPs in PP matrix, the obtained UiO-66@AgNPs nanoparticles were first treated with Ag⁺ and triisobutylaluminum (TIBA) successively, and then used as a carrier of the methylaluminoxane (MAO) cocatalyst to accomplish the heterogenization of a typical zirconium-based metallocene catalytic system. Antibacterial PP was further efficiently produced through the heterogeneous polymerization of propylene by using the target heterogeneous catalytic system. The obtained PP/UiO-66@(AgNPs/Ag⁺) nanocomposite showed strong antibacterial ability with 99.48% antibacterial activity at a very low Ag content of 0.23 wt % due to the excellent dispersion of the antibacterial agents in the PP matrix. Meanwhile, the thermal stability of PP was significantly enhanced by the introduction of UiO-66@(AgNPs/Ag⁺) antibacterial agents.