No abstract

Scanning electron micrographs of a solvent-extracted sheared polyethylene (PE) blend revealed, for the first time, an unexpected shish-kebab structure with multiple shish. The blend contained 2 wt % of crystallizing ultrahigh molecular weight polyethylene (UHMWPE) and 98 wt % of noncrystallizing PE matrix. The formation of multiple shish was attributed to the coil-stretch transition occurring in sections of UHMWPE chains. Synchrotron x-ray data provided clear evidence of the hypothesis that multiple shish originate from stretched chain sections and kebabs originate from coiled chain sections, following a diffusion-controlled crystallization process.

Here, we report a new Ti(IV)-based porous metal-organic framework (MOF) (NTU-9), which displayed strong absorption in the visible region with a bandgap of 1.72 eV. The electronic structure and bandgap were further investigated by DFT calculations. Photoelectrochemical studies indicated that NTU-9 is photoactive under visible light illumination (λ > 400 nm) and acts as a p-type semiconductor. The results demonstrated that Ti(IV)-based MOFs could be promising visible-light photocatalysts for energy conversion and environmental remediation.