dc.description.abstract | Since science and technology develop fast, a number of investigators pay attention to polymer nanomaterials. Among them, the study regarding to block copolymer has become a critical issue. In this study, we focused to synthesize a triblock copolymer, and then the synthesized chemicals with a long carbon were embedded in the interlayer of clay (montmorillonite) to increase basal spacing. The produced clay composite was characterized using various instruments. The prepared composite materials were applied to uptake non-ionic organic pollutants (NOCs) and inorganic metal ions.
Electronic properties, hydrophilicities, block copolymer size and synthesis sequence for the monomer to form triblock copolymer could affect the properties of composite materials. In this study, a method of “Reversible Addition-Fragmentation Chain Transfer (RAFT)” was used to prepare the triblock copolymer. The block copolymers consist of methyl methacrylate (M), dimethylaminoethyl methacrylate (D), methacrylic acid (A). The amino-group in D possesses the positive charge, which can be regarded as a cationic surfactant. Hydrogen ion in A could dissociate to form anionic surfactant under the pH >7. M possesses the relatively higher hydrophobicity that dissociates difficultly. In the montmorillonite, it was modified with two different layers. After drying, the triblock copolymer was added to the modified soil. Then, the sample was dried to obtained a composite-clay.
The result indicated that the clay composites synthesized in this study can uptake organic pollutants, (benzene, toluene, ethylbenzene and xylene, BTEX), and metal ions (Cu2+, Pb2+and Cr6+). Although the adsorptive amount of Cr6+ is lower than that in literature, the adsorbent can effectively remove Cr6+ from aqueous solution. For BTEX, the CS211modified clay can generate the best adsorption effect. Moreover, logkom values for benzene, toluene, ethylbenzene, and xylene, were 2.37, 2.83, 3.24, and 3.25, respectively. As for the cationic meatal ions, the adsorptive amounts are higher than those in literature. The maximum adsorption capacities for Cu2+ and Pb2+ are 45.2 and 80 mg/g, respectively. The result demonstrated the clay had been modified successfully. The adsorption experiment for the organic compounds on the modified clay examined the level of the soil disintegration after the modification and whether the produced adsorbents uptake inorganic pollutants or not. According to the research results, CS112 modified clay was regarded as the best adsorbent to remove the test pollutants.
Key words:triblock copolymer, modified clay, RAFT polymerization, layer column, BTEX, Cr6-, Cu2+, Pb2+ | en_US |