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ABSTRACT Construction of a highly hydrophilic polymer surface with excellent long-term stability underwater is a great challenge. In this paper, a facile ultraviolet (UV) curing technique was employed to realize the three-dimensional (3D) grafting of poly(ethylene glycol) diacrylate (PEGDA, molecular weight: 400, 600, and 1000 g/mol) on a bisphenol A epoxy acrylate (BEA) sheet. The cross section morphology, surface chemical composition, and wettability of the sheets were monitored using an optical microscope, an attenuated total reflectance Fourier transform infrared spectroscope, and a water contact angle analyzer, respectively. The PEGDA-grafted epoxy sheets displayed a highly hydrophilic surface and meanwhile possessed excellent stability underwater, despite the molecular weight of PEGDA. In contrast, the PEGDA/BEA blend sheets are easily damaged underwater, due to strong swelling. In addition, the PEGDA1000-grafted BEA sheet demonstrated good antifouling performance in a natural marine environment. Nevertheless, its long-term antifouling is not satisfactory, being presumably due to hydrolysis or biodegradation of the PEG segments. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43972. [ABSTRACT FROM AUTHOR]

Microplastic pollution has aroused great concern in inland waters. Freshwater is the transport routes and potential sources for plastic fragments to the oceans. However, information especially about the occurrence of microplastics in freshwater systems is unclear in certain key areas. This work studied the distribution and characteristics for microplastics in the downstream area of West River. Both sediment and surface water detected microplastics with abundance ranging from 2560 to 10,240 items/kg and 2.99 to 9.87 items/L, respectively. Small size (<0.5 mm) and fiber were the main size and type in both surface waters and sediments. Polypropylene, polyethylene, polyethylene, polyvinyl chloride and polyethylene terephthalate were the polymer types of microplastics, as identified using a Fourier transform infrared spectrometer. In addition, findings here might be in consideration of studying about the distribution of microplastics and the degree to which they were influenced by the use of land. In descending order, the highest microplastics abundance was observed in commercial/public/recreational > residential > industrial > natural areas. Our results indicate the occurrence of high abundance microplastics in river impacted by human activities, and suggest that spatial distribution of microplastics varies between different land use areas. Unlabelled Image • Microplastics occurrence in West River were investigated. • The abundance of microplastics in water samples is lower than that in sediments. • Fiber and small size (<0.5 mm) were the dominant types and size in samples. • The spatial distribution of microplastics varies between different land use areas. [ABSTRACT FROM AUTHOR]

Microplastics are widespread in the environment and might transport readily by ocean currents, wind and atmospheric deposition. Simultaneously, antibiotics and heavy metals could often be detected in the environment. They are both positively charged, it is necessary to clarify the interactions of these pollutants with microplastics when they were coexist. In this study, the most commonly used polystyrene (PS) was selected as a representative microplastic. This study investigated the effect of Cd(II) on the sorption of TYL by PS in different coexistence systems. The results showed that: in the composite system, when TYL and Cd(II) coexist, the presence of Cd(II) could inhibit the sorption of TYL by PS, and the inhibitory effect increases with the increase of the concentration of Cd(II), indicating that competitive sorption dominates the sorption. When PS adsorbed Cd(II) first and then adsorbed TYL, the presence of Cd(II) was conducive to the sorption of TYL, and the sorption strengthened with the increase of Cd(II) concentration, indicating that the complexation between TYL and Cd(II) enhanced the sorption of TYL. In addition, initial pH values and ionic strength were essential in the sorption process. Therefore, this study could provide an important basis for evaluating the environmental behavior and ecological risk of microplastics in the process of compound pollution. Image 1 • The effect of Cd(II) on the sorption of TYL by PS was first studied. • The Cd(II) addition inhibited the sorption of TYL by PS in coexist systems. • The Cd(II) addition enhanced the sorption of TYL by PS when Cd(II) first sorbed by PS. • Competition and complexation interactions were involved in the sorption process. [ABSTRACT FROM AUTHOR]

The objective of this work is to find a simple and environmentally friendly way to prepare high efficiency adsorbent from maize stover by cellulase. The characteristics of the original maize cob (MC), maize husk (MH), maize straw (MS), and its cellulase modified form (MMC, MMH and MMS) were detected by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). Batch adsorption experiments indicated that the adsorption followed the pseudo-second-order kinetic model, and the adsorption capacity of sulfamethazine (SMT) to adsorbents was in order of MMC > MMS > MMH > MC > MS > MH. The adsorption isotherm data of SMT on original materials were consistent with Freundlich models, while Henry models were more suitable for the modified materials. The adsorption was affected by pH and ionic strength which demonstrated the interaction between π-π EDA and H bonds might be an important factor in the adsorption of SMT on maize stover. The results of FTIR and two-dimensional correlation spectroscopy (2D-COS) analysis further demonstrated that oxhydryl and aromatic structures in the modified maize stover could interact with SMT via H bonds and π-π EDA interaction, respectively. This work provides a green way to remove SMT from aqueous solution, and new insights into the mechanisms of adsorption of SMT on stover materials. Unlabelled Image • The adsorption capacity of maize stover was enhanced after cellulase modified. • pH and ionic strength can apparently affect sulfamethazine removal by maize stover. • The changing order of functional groups was analyzed by 2D-FTIR-COS. • Surface complexation played an important role in the adsorption on modified stover. [ABSTRACT FROM AUTHOR]