Addition of filler to polylactic acid (PLA) may affect its crystallization behavior and mechanical properties. The effects of talc and hydroxyapatite (HA) on the thermal and mechanical properties of two types of PLA (one amorphous and one semicrystalline) have been investigated. The composites were prepared by melt blending followed by injection molding. The molecular weight, morphology, mechanical properties, and thermal properties have been characterized by gel permeation chromatography (GPC), scanning electron microscope (SEM), instron tensile tester, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and dynamic mechanical analysis (DMA). It was found that the melting blending led to homogeneous distribution of the inorganic filler within the PLA matrix but decreased the molecular weight of PLA. Regarding the filler, addition of talc increased the crystallinity of PLA, but HA decreased the crystallinity of PLA. The tensile strength of the composites depended on the crystallinity of PLA and the interfacial properties between PLA and the filler, but both talc and HA filler increased the toughness of PLA.

The pipeline transportation of waxy crude oil is a problem both at home and abroad. In this paper, a novel nanohybrid pour-point depressant (PPD) was used to decrease the pour point and viscosity of waxy crude oil. The pour point and apparent viscosity of waxy crude oil was decreased significantly upon addition of the nanohybrid PPD, and the long-term stability of the nanohybrid PPD was superior to that of a conventional ethylene-vinyl acetate copolymer PPD. Polarized optical microscopy and X-ray diffraction were used to study the effect of the nanohybrid PPD on the crystallization of crude oil. Addition of the nanohybrid PPD reduced the amount of wax crystals, prevented their aggregation, and reduced the temperature at which the crude oil started to crystallize. The significant effect of this nanohybrid PPD on the pour point and viscosity depressing of crude oil is of great importance for facilitating the safe, efficient and energy-minimized transportation of waxy crude oil.

It is known that ultraviolet (UV) radiation is harmful to human health and affects the long-term stability of many organic materials. It has recently been discovered that blue radiation also poses a danger. In this study, epoxy–ZnO/CdS (EP–ZC) nanocomposites capable of shielding both UV and blue radiation were developed. First, ZnO/CdS nanoparticles were synthesized through the growth of CdS on prefabricated ZnO quantum dots (ZnO QDs). In contrast to ZnO QDs, which only absorb a portion of UV light, the ZnO/CdS nanoparticles exhibited strong absorption over the wavelength region extending from UV light to blue light. Further, their absorption-band range could be controlled by adjusting the Zn/Cd molar ratio. In situ polymerization was employed to prepare the EP–ZC nanocomposites, which were highly transparent at wavelength greater than 500 nm. It was found that the EP–ZC nanocomposites exhibited strong UV-shielding capability and could almost completely block UV light between 200–400 nm as well as more than 80% of the blue light between 400–450 nm when they contained 0.3 wt% ZnO/CdS nanoparticles. Finally, their optical transparency to visible light in the region beyond blue light was the same as that of pure epoxy due to the uniform dispersion of nanoparticles.