Atom transfer radical polymerization (ATRP) of glycidyl methacrylate (GMA) at roomtemperature was carried out in a methylethyl ketone/1-propanol (in 7/3 volume ratio) solution,initiated and catalyzed by ethyl 2-bromop...Atom transfer radical polymerization (ATRP) of glycidyl methacrylate (GMA) at roomtemperature was carried out in a methylethyl ketone/1-propanol (in 7/3 volume ratio) solution,initiated and catalyzed by ethyl 2-bromopropionate (BRA)/CuC1/2,2＇ -bipyridine (BPY). Polymer ofGMA with planned molecular weight and narrow molecular weight distribution was obtained. In caseof bulk polymerization with the same initiator and catalyst the molecular weight of the polymerobtained was 1.5～2. 1 times greater than that of the above one. By using 1-phenylethyl chloride(PECl)/CuCl/BPY as catalyst controlled ATRP of GMA has failed whether it was in bulk or insolution.展开更多
The self assemble behavior of amphiphilic poly(styrene b acrylic acid), P(S b AA), in selective solvents was studied by dynamic light scattering(DLS). The diameters of micellae were found to be decreased and then incr...The self assemble behavior of amphiphilic poly(styrene b acrylic acid), P(S b AA), in selective solvents was studied by dynamic light scattering(DLS). The diameters of micellae were found to be decreased and then increased with the increase in the concentration of the calcium ion in solvent. The average diameter of micellae was minimum when the concentration of the CaCl 2 was 0 2 g/L . In addition, the distribution of micellae became narrow with the increase in the ethylenediamine concentration.展开更多
The micelles behavior of amphiphilic block copolymer P（Styrene\|b\|acrylic acid）, in aqueous solvent was studied by dynamic light scattering and TEM techniques. The diameters of micelle decreased and then increased ...The micelles behavior of amphiphilic block copolymer P（Styrene\|b\|acrylic acid）, in aqueous solvent was studied by dynamic light scattering and TEM techniques. The diameters of micelle decreased and then increased with the decrease of the pH of the solution, and the similar phenomenon was also detected with the increase of the concentration of the calcium ion. Without added acid, the micelles were small spheres of low polydispersity with an average diameter 48 nm. When the value of pH was less than 2, the micelles were unstable. It was found that the Ca\+\{2+\} was linked with the carboxyl in the same micelle when the concentration of the CaCl\-2 was less than 0\^2 mg/mL. The diameter of micelle was smaller than the one without Ca\+\{2+\}. The Ca\+\{2+\} was linked with the carboxyl between the different micelles when the concentration of the CaCl\-2 was more than 0\^5 mg/mL and the micelle was unstable. The diameters of micelles（from 37 nm to 100 nm） can be controlled by adding an appropriate concentration of CaCl\-2 between 0\^2\0\^5 mg/mL.展开更多
文摘Atom transfer radical polymerization (ATRP) of glycidyl methacrylate (GMA) at roomtemperature was carried out in a methylethyl ketone/1-propanol (in 7/3 volume ratio) solution,initiated and catalyzed by ethyl 2-bromopropionate (BRA)/CuC1/2,2＇ -bipyridine (BPY). Polymer ofGMA with planned molecular weight and narrow molecular weight distribution was obtained. In caseof bulk polymerization with the same initiator and catalyst the molecular weight of the polymerobtained was 1.5～2. 1 times greater than that of the above one. By using 1-phenylethyl chloride(PECl)/CuCl/BPY as catalyst controlled ATRP of GMA has failed whether it was in bulk or insolution.
文摘The self assemble behavior of amphiphilic poly(styrene b acrylic acid), P(S b AA), in selective solvents was studied by dynamic light scattering(DLS). The diameters of micellae were found to be decreased and then increased with the increase in the concentration of the calcium ion in solvent. The average diameter of micellae was minimum when the concentration of the CaCl 2 was 0 2 g/L . In addition, the distribution of micellae became narrow with the increase in the ethylenediamine concentration.
文摘The micelles behavior of amphiphilic block copolymer P（Styrene\|b\|acrylic acid）, in aqueous solvent was studied by dynamic light scattering and TEM techniques. The diameters of micelle decreased and then increased with the decrease of the pH of the solution, and the similar phenomenon was also detected with the increase of the concentration of the calcium ion. Without added acid, the micelles were small spheres of low polydispersity with an average diameter 48 nm. When the value of pH was less than 2, the micelles were unstable. It was found that the Ca\+\{2+\} was linked with the carboxyl in the same micelle when the concentration of the CaCl\-2 was less than 0\^2 mg/mL. The diameter of micelle was smaller than the one without Ca\+\{2+\}. The Ca\+\{2+\} was linked with the carboxyl between the different micelles when the concentration of the CaCl\-2 was more than 0\^5 mg/mL and the micelle was unstable. The diameters of micelles（from 37 nm to 100 nm） can be controlled by adding an appropriate concentration of CaCl\-2 between 0\^2\0\^5 mg/mL.
