To improve the adsorption selectivity towards hexavalent chromium anion (Cr(VI)), surface Cr(VI)-imprinted polypropylene (PP) fibers were fabricated by the plasma-mediated grafting strategy. Hence, a non-thermal Rradio frequency discharge plasma irradiation followed by a gaseous phase grafting was used to load acrylic acid (AA) onto PP fibers, which was afterwards amidated with triethylenetetramine and subjected to imprinting with a Cr(VI) template. The plasma irradiation conditions, i.e., gas species, output power, pressure, and time, were optimized and then the influence of grafting time, pressure, and temperature on the grafting degree of AA was investigated. Scanning electron microscopy and Fourier transform infrared spectroscopy were used for the characterization of pristine and modified fibers and to confirm the synthesis success. The hydrophilicity of modified fibers was greatly improved compared with pristine PP fibers. The adsorption thermodynamics and kinetics of Cr(VI) were investigated, as well as the elution efficiency and reusability. The prepared imprinted fibers showed superior adsorption selectivity to Cr(VI) compared with non-imprinted fibers. Finally, the stability of the imprinted fibers against the oxidation ability of Cr(VI) is discussed.

Active macromolecular free radicals were generated on polypropylene (PP) fiber surfaces by argon plasma irradiation, and surface-modified PP fibers (PP-g-St fibers) were prepared by in situ grafting reaction of styrene monomers (St). The prepared samples were characterized by Fourier transform infrared, NMR, X-ray photoelectron spectroscopy, scanning electron microscopy, and thermogravimetric analysis. Effects of reaction parameters on grafting percentage were studied, and adsorption capacities of PP-g-St fibers for benzene, toluene, and xylene (BTX) were evaluated. Regeneration adsorption efficiencies after adsorption of pure BTX and BTX emulsion and solution in water were explored. The results indicated that, using pure St as the monomer, the optimum input power, irradiation time, and grafting reaction time are 90 W, 3 min, and 3 h, respectively, and the grafting percentage of St reached 5.7% when pure St was used. The characterization results demonstrated that St was grafted onto the surface of the PP fibers. Compared to pristine PP fibers, the adsorption capacities of PP-g-St fibers toward toluene and xylene emulsions and solutions in water increased. In addition, regeneration adsorption efficiencies of modified fibers remained >90% after six cycles of regeneration adsorption experiments, which showed excellent regeneration ability.

Zinc oxide nanoparticles (ZnO NPs) are used as antifungal agents and imparted in starch paste. The zinc oxide nanoparticles are synthesized using starch as a stabilizing agent under sonochemical irradiation, and then used in the preparation of ZnO NPs‐based starch paste. The effects of starch and ultrasonic irradiation on the formation of ZnO NPs are subsequently investigated. Characterization by X‐ray diffraction and transmission electron microscopy reveals that ZnO NPs synthesized under an optimal condition are highly dispersed and well‐defined crystals with diameters of approximately 5 nm. The antifungal performance of ZnO NPs‐based starch paste is evaluated under a high temperature and humidity environment, and is compared with traditional fungicides, alum, and pure terephthalic acid (PTA). In addition, the paste shows negligible toxicity and deterioration to the mechanical properties of the mounted paper. Lastly, the paper mounted with ZnO NPs‐based starch paste shows superior antifungal performance, an essential property protecting paper documents from mold growth, compared to pristine starch paste.

Waste circuit boards particles (CBPs) were utilized as a reinforcing filler to prepare bulk molding composites (BMCs) for the manufacture of composite manhole covers (CMCs) without reinforcing ribs. The effects of CBPs and conventional CaCO 3 on the mechanical properties of the BMCs were comparatively determined. Compared to CaCO 3 , CBPs showed a higher compatibility with unsaturated polyester resin (UPR) while effectively improving the fluidity of premix and the mechanical properties of the BMC. To enhance the interfacial adhesion between the glass fiber (GF) and UPR, three kinds of amine, epoxy, and vinyl modified silanes (namely KH-550, KH-560, and KH-570, respectively) were used. The surface tension (c) of the GF significantly decreased upon modification with the coupling agents. Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM) characterizations revealed a strong adhesion between the GF and UPR, thereby enhancing the mechanical properties of the composite material. The BMC material showed optimal flexural strengths upon addition of KH-560 and KH-570 coupling agents at 4 wt%. With the aim of evaluating its mechanical performance, a constant loading test combined with an ANSYS finite element analysis was performed over the prepared CMC. According to the constant loading test, the CMC material showed a stress loading of 7.8 tons, which was close to the value obtained by ANSYS simulation. POLYM. COMPOS., 00:000-000, 2017. V C 2017 Society of Plastics Engineers