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To alleviate the adverse effects of pesticide residues on the environment, development of a more safe, economical, and reliable usage approach of pesticides is critically urgent. In the present study, a novel pesticide carrier LA-NSM (lauric acid-modified Nitraria seed meal) with controlled release property was prepared through grafting esterification of lauric acid onto Nitraria seed meal substrates. The structure of the obtained samples was characterized by Fourier-transform infrared spectroscopy, scanning electron microscopy, and contact angle measurements. The results indicated that LA-NSM products had a well-defined hydrophobic surface and irregular holes for efficient loading of pesticide molecules. Deltamethrin (DEL), a representative insoluble pyrethroid insecticide in water, was deliberately selected as the index pesticide to evaluate the loading and releasing efficiency of LA-NSM. The loading capacity of LA-NSM for DEL can reach about 1068 mg/g. pH, humidity of soil, and temperature had a significant influence on controlled release performance of LA-NSM@DEL. Moreover, the releasing kinetics of LA-NSM@DEL composites could be fitted well with the Higuchi model. Overall, the highly hydrophobic property, excellent loading, and controlled release ability of LA-NSM made it a promising candidate in agricultural applications. [ABSTRACT FROM AUTHOR]
NSM-<i>g</i>-P(MMA-<i>co</i>-BA) resin with super oil-absorbent capability was prepared by grafting co-polymerization using Nitraria seeds meal as filler, methyl-meth-acrylate (MMA) and butyl-acrylate (BA) as monomers, <i>N,N′</i>-methylene-bis-acrylamide (MBA) as crosslinker and peroxide-benzoyl (BPO) as initiator. The structure of obtained products was analyzed using Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM), respectively. The oil absorbency, reusability, oil-retention capacity, thermodynamics, and the removal of oil from the surface of 0.9 wt% NaCl solutions were examined further. The results showed that NSM-<i>g</i>-P(MMA-<i>co</i>-BA) can absorb lubrication up to 29.6 times of its weight, 24.3 times for colza oil, 22.7 times for diesel, and 21 times for gasoline. The exhausted NSM-<i>g</i>-P(MMA-<i>co</i>-BA) can be recollected and recovered through extraction or drying approach. More importantly, the oil sorption capacity of recovered NSM-<i>g</i>-P(MMA-<i>co</i>-BA) only has a slight decline after six sorption cycles. The thermodynamic studies indicated that adsorption procedure with complex physical and chemical sorption is spontaneous and exothermic. In general, the present composite resins have exhibited potential applications in cleanup of oil spills because of their good hydrophobicity, lipophilicity, and excellent network structure. Also, the findings of this study might provide a convenient and economic method for fast and selective removal of oil from surface of wastewater. POLYM. COMPOS., 39:1051-1063, 2018. © 2016 Society of Plastics Engineers