Stretching-induced interfacial crystalline structures and relevant mechanical properties in melt-spun polypropylene/whisker composite fibers

Characterization and evaluation of the leachability of bottom ash from a mobile emergency incinerator of COVID-19 medical waste: A case study in Huoshenshan Hospital, Wuhan, China

To dispose of the medical waste generated during the COVID-19 pandemic, a new type of mobile emergency incinerator (MEI) was used in Huoshenshan Hospital, Wuhan, China, and consequently, it produced a number of medical bottom ashs (MBAs). In this study, the characterization and environmental risk evaluation of these MBAs were conducted to evaluate the disposal effect of this MEI used during the pandemic. Three types of leaching tests, EN 12457-2, TCLP 1311, and HJ/T 299-2007, were compared to investigate the release behaviors of major and trace elements from these MBAs. Lack of detection of COVID-19 in MBAs showed that this mobile emergency incinerator could thoroughly eliminate the COVID-19 virus in medical wastes to avoid secondary transmission. The results indicated that the increasing usage of chlorinated disinfectants and physiological saline solutions resulted in high Cl contents in MBAs. In addition, the increasing usage of polypropylene (PP) products changed the chemical properties and compositions of MBAs, with Ca as the main element. The leachability investigation revealed that the main metals in leachates were Ca, Na and K, and the toxic heavy metals such as Zn, Pb, Cu, and Cr in MBAs were difficult to extract because of the high pH (>12) of these MBAs. This study could provide consultation for the treatment and management of MBAs produced from MEIs dealing with emergent infectious diseases such as COVID-19.

Fabrication of a polymer/aligned shish-kebab composite: microstructure and mechanical properties

A shear-induced ultrahigh molecular weight polyethylene (UHMWPE) shish-kebab mat (USKM) has been used as a filler to prepare a reinforced composite and the tensile strength and modulus of the composite are significantly improved.

Suppressing the skin–core structure in injection-molded HDPE parts via the combination of pre-shear and UHMWPE

Skin–core structure of a injection-molded high density polyethylene (HDPE) part is largely relieved due to the synergetic effects of pre-shear and UHMWPE, leading to a remarkable increase of tensile strength.

THE PERFORMANCE OF BARIUM SULFATE NANOPARTICLES/POLYPROPYLENE HYBRID MULTIFILAMENT

Nanosize barium sulfate ( BaSO 4) particles prepared with dodecyl benzene sulfonic acid (DBSA) in ethanol–water reaction system are used to prepare BaSO4 /polypropylene (PP) nanocomposites by melt mixing method. It is then made into hybrid fibers by melt spinning and subsequent drawing with different ratios. The hybrid fibers are characterized by rheology, morphology, thermal stability and mechanical properties, respectively. The results indicate that the DBSA-modified BaSO4 can improve the spinnability of BaSO4 /PP hybrid multifilament even at high BaSO4 nanoparticles concentration. DBSA can be used as compatibilizer to enhance the interface interaction of BaSO4 /PP nanocomposites, because DBSA contains both hydrophobicity long alkyl chain and hydrophilic sulfonic group. Therefore, it can improve the performances of BaSO4 /PP hybrid multifilament.