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
用扫描电子显微镜对聚苯乙烯 b 聚丙烯酸 (PS b PAA)嵌段共聚物在水中自组装形貌进行了观察。结果表明 :外界环境和制样方法能够影响聚合物的自组装和聚集情况。 0℃时 ,PS38 b PAA2 10 胶束聚集形成纺锤状结构。而在临界条件下 ,缓慢...用扫描电子显微镜对聚苯乙烯 b 聚丙烯酸 (PS b PAA)嵌段共聚物在水中自组装形貌进行了观察。结果表明 :外界环境和制样方法能够影响聚合物的自组装和聚集情况。 0℃时 ,PS38 b PAA2 10 胶束聚集形成纺锤状结构。而在临界条件下 ,缓慢改变体系冷冻 解冻循环次数 ,则会得到这些纺锤结构的花状聚集体。展开更多
The halogen-terminated polymers （PS—X） were obtained by living free radical polymerization. Through the end-group transformation action of AgClO4, poly（styrene-b-2-methyl-2-oxazoline） block copolymer [P（s-b-Me-...The halogen-terminated polymers （PS—X） were obtained by living free radical polymerization. Through the end-group transformation action of AgClO4, poly（styrene-b-2-methyl-2-oxazoline） block copolymer [P（s-b-Me-OXZ）] was synthesized by transforming the living free radical polymerization into ring-opening polymerization of 2-methyl-2-oxazoline.The obtained copolymers were characterized by SEC, IR and 1H NMR. The suitable polymerization conditions for block copolymer synthesis were studied.展开更多
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.
文摘The halogen-terminated polymers （PS—X） were obtained by living free radical polymerization. Through the end-group transformation action of AgClO4, poly（styrene-b-2-methyl-2-oxazoline） block copolymer [P（s-b-Me-OXZ）] was synthesized by transforming the living free radical polymerization into ring-opening polymerization of 2-methyl-2-oxazoline.The obtained copolymers were characterized by SEC, IR and 1H NMR. The suitable polymerization conditions for block copolymer synthesis were studied.
