Nickel-catalyzed in situ synthesis of UHMWPE/TiO composites with enhanced mechanical properties and adjustable photocatalytic degradabilities.

Expanding the application field of polyolefin materials through functionalization has been a research hotspot in the past three decades. Here, a TiO-supported anilinenaphthoquinone nickel catalyst was assembled and applied for in situ ethylene polymerization with high activity (>2000 kg molh) to produce ultra-high molecular weight polyethylene (UHMWPE)/TiO composites with unique physicochemical performance. The UHMWPE/TiO composite films and fibers prepared by in-situ ethylene polymerization are superior to the samples from the blend system in issues such as TiO dispersibility, mechanical property, and photocatalytic degradability. The mechanical properties (strength up to 26.8 cN/dtex, modulus up to 1248.8 cN/dtex) of the obtained UHMWPE/TiO composite fibers are significantly improved with a very low dosage of TiO (as low as 1.4 wt‰). Moreover, UHMWPE/TiO composites obtained by coating AlO and SiO on the surface of TiO not only retain the strong absorption of ultraviolet rays, but also effectively weaken the photocatalytic degradation effect.