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The preparation, the spectroscopic characterization, the crystal structure and chemical reactions of the new six-membered heterocyclic betaine2 are reported; 2 is a representative of a possibly large group of yet unkonwn betaines of the general structure 8. 相似文献
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M. H. Litt C. S. Lin I. M. Krieger 《Journal of polymer science. Part A, Polymer chemistry》1990,28(10):2777-2792
Block copolymers of poly(N-t-butylbenzoyl ethylenimine) and poly(N-propionyl ethylenimine) (Bx/Ey and Bx/Ey/Bx) or poly (N-lauroyl ethylenimine) and poly (N-propionyl ethylenimine) (Ux/Ey) were synthesized by cationic ring-opening polymerization of 2-substituted δ2-oxazolines. Inverse emulsions (salt-in-oil) were made using these block copolymers as emulsifiers, hydroxy-terminated polybutadiene (HTPB) as the nonpolar phase and methyl ammonium ethane sulfonate (MAES) as the polar phase. These inverse emulsions (S/O) were then cured using a triisocyanate to give a dispersion of molten salt (MAES) droplets in polyurethane. Pore sizes of these cured inverse emulsions were measured from scanning electron photomicrographs as a function of stirring time and concentrations of block copolymer and molten salt. The results indicate that pores with diameters in the range of 1.5 X 10?6 m can be obtained using triblock copolymer Bx/Ey/Bx, and that the surfactant molecules can be spread as a monolayer at the MAES-HTPB interface. 相似文献
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RITVA LINDBERG GORAN SUNDHOLM JOHAN SJö BLOM PETRI AHONEN ESKO I. KAUPPINEN 《Journal of Dispersion Science and Technology》2013,34(1-2):715-722
The zeta-potentials of silica, copper, platinum and gold particles have been measured as a function of pH. The isoelectric points were found to be at pH 3.0, 5.8, 3.0 and 3.5, respectively. In the pH range 3.0 to 5.8 copper and silica particles are oppositely charged and accordingly the coating of silica with copper particles could be demonstrated. In the case of gold and platinum the sign of the charge is such that direct adhesion to silica particles cannot be expected and this was also demonstrated in the case of platinum. 相似文献
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This paper reports the synthesis of 1-(1-methylhydrazino)-2-propanethiol and the results of a study of its reactions with benzaldehyde, benzonitrile, benzoyl chloride, triethyl orthoformate, succinonitrile, cyanogen bromide, and cyclopropylcyanide to give a thiadiazine directly or a product which can be converted to a thiadiazine. It also reports the condensation of 1-(1-methylhydrazino)-2-propanethiol with carbon disulfide to yield a 2-thiazolidinethione. 相似文献