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Abstract: Using cetyltrimethylammonium bromide (CTAB) as organic treatment agent, phenylmethylsilicone/organic montmorillonite (OMMT) nanocomposites were prepared by in-situ intercalative polymerization. The internal structure and morphology of the nanocomposites were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM) and transmission electron microscope (TEM). Mechanical properties, high temperature resistance and barrier performance for gas and water were also studied. The results show that molecules of silicone chains insert into the layer of montmorillonite (MMT), and the interlayer distance of MMT is expanded effectively after polymerization of phenylmethylsilicone prepolymer and methyl methacrylate, even forming exfoliated nanocomposites. The silicone/OMMT nanocomposite containing 8wt% OMMT has better high temperature resistance and barrier properties with low thermal weight loss of 25% at 750°C. The nanocomposite, containing 6wt% OMMT, has better mechanical performance with tension strength of 6.264MPa, which is five times more than that of pure silicone. When the nanocomposite contains 4wt% OMMT, the compression strength is 11.503MPa, which is four times bigger than that of pure silicone. [Copyright &y& Elsevier]

Abstract: A novel hypercrosslinked polymeric adsorbent of LM-6 was prepared by post-crosslinking reaction with 2-naphthol. Bromoethane was used as crosslinking reagent to substitute poisonous organic compound of chloromethyl methylether. Selective adsorption on LM-6 in mixture solution which consisting of 2-naphthol and naphthalene shows that the adsorption of 2-naphthol and naphthalene in aqueous solution are mainly pushed by physical interaction. The adsorption of 2-naphthol is also partly pushed by chemical interaction. The adsorptive enthalpy illuminates that there exists hydrogen-bonding between 2-naphthol and LM-6. Owning to hydrogen-bonding, the adsorption capacity of 2-naphthol on LM-6 is markedly higher than that of naphthalene. In aqueous solution, the adsorption process contains two steps: desorption of water first and then adsorption of solute. Dynamic analysis shows that adsorption capacity of 2-naphthol is higher than that of naphthalene. The adsorption rate is mainly affected by the diffusion of liquid membrane, the diffusion inside particulate or coordinated effect. [Copyright &y& Elsevier]