The interactions between the components of FeCl3-Al (i-Bu)3-bipyridine -catalyst were studied by the electric conductivity of these components in a hydrogenated gasoline medium at 25℃. It was found that Al (i-Bu) ex...The interactions between the components of FeCl3-Al (i-Bu)3-bipyridine -catalyst were studied by the electric conductivity of these components in a hydrogenated gasoline medium at 25℃. It was found that Al (i-Bu) existed in an 3 associated state and was then dissociated into ion pairs. The reaction between FeCl3 and Al (i-Bu)3 is the chief reaction in the formation of nano-sized particles. Simultaneously, Al (i-Bu)3 reduced Fe3+ into Fe2+. The reaction between Fe2+ and bipy generated a Fe (bipyridine)2+ complex compound, which prevented Al (i-Bu)3 from reducing Fe2+ to a lower valence (Fe+, Fe0). The excessive Al (i-Bu)3 was dissociated into ion pairs and formed a double layer, which stabilized the nano-sized particles.展开更多
Polymerization of octodecyl acrylate is studied in four solvents — carbon tetrachloride, chloroform, methylbenzene and tetrachloroethane. Experimental results indicate that the sequence of chain transfer constants i...Polymerization of octodecyl acrylate is studied in four solvents — carbon tetrachloride, chloroform, methylbenzene and tetrachloroethane. Experimental results indicate that the sequence of chain transfer constants in solvents is: carbon tetrachloride>chloroform>methylbenzene>tetrachloroethane in the polymerization of octadecyl acrylate. Influences of four solvents on solubility of polyoctadecyl acrylate prove not the same. In chloroform, polyoctadecyl acrylate shows the highest relative viscosity and the lowest chain termination rate constant. In higher conversion, the average relative molecular weight of polyoctadecyl acrylate depends mainly on the chain transfer constant of the solvent. Under the circumstance of monomer conversion higher than 30%, the viscosity effect induced by polymeric molecular shape in the solvents have a strong influence on the relative molecular weight of the polymer obtained.展开更多
文摘The interactions between the components of FeCl3-Al (i-Bu)3-bipyridine -catalyst were studied by the electric conductivity of these components in a hydrogenated gasoline medium at 25℃. It was found that Al (i-Bu) existed in an 3 associated state and was then dissociated into ion pairs. The reaction between FeCl3 and Al (i-Bu)3 is the chief reaction in the formation of nano-sized particles. Simultaneously, Al (i-Bu)3 reduced Fe3+ into Fe2+. The reaction between Fe2+ and bipy generated a Fe (bipyridine)2+ complex compound, which prevented Al (i-Bu)3 from reducing Fe2+ to a lower valence (Fe+, Fe0). The excessive Al (i-Bu)3 was dissociated into ion pairs and formed a double layer, which stabilized the nano-sized particles.
文摘Polymerization of octodecyl acrylate is studied in four solvents — carbon tetrachloride, chloroform, methylbenzene and tetrachloroethane. Experimental results indicate that the sequence of chain transfer constants in solvents is: carbon tetrachloride>chloroform>methylbenzene>tetrachloroethane in the polymerization of octadecyl acrylate. Influences of four solvents on solubility of polyoctadecyl acrylate prove not the same. In chloroform, polyoctadecyl acrylate shows the highest relative viscosity and the lowest chain termination rate constant. In higher conversion, the average relative molecular weight of polyoctadecyl acrylate depends mainly on the chain transfer constant of the solvent. Under the circumstance of monomer conversion higher than 30%, the viscosity effect induced by polymeric molecular shape in the solvents have a strong influence on the relative molecular weight of the polymer obtained.
