PS-b-PEO-b-PS三嵌段共聚物在选择性溶剂中的胶束化

应用原子转移自由基聚合,制备了一组窄分布的PS-b-PEO-b-PS三嵌段共聚物。用^1HNMR和TEM表征了它们在选择性溶剂中的胶束化行为。^1HNMR结果表明,共聚物苯环上的质子峰出现在良溶剂(CHCl~3)中,而在选择性溶剂水中消失,证明上述三嵌段共聚物在选择性溶剂水中可逆自组装成以PS为核、PEO为壳的胶束。通过TEM考察了胶束的形状及大小,发现体系胶束尺寸呈多分散、粒径大,对形成的原因也提出了可能的解释。

The micellization of PS-b-PEO-b-PS triblock copolymers in selective solvent water

The micellization of well - defined PS - b - PEO - b - PS triblock copolymers in selective solvent has been characterized using 1H NMR and TEM technologies. The 1H NMR investigations reveal that the peaks of phenyl ring protons show up in CHCl3 (good solvent) and disappear in water (selective solvent) . Therefore, the triblock copolymers self - assemble reversibly to form micelles with a core composed of the insoluble PS blocks and a shell of water - solvated soluble PEO blocks. The shape of micelles have been observed and the radius have been measured by TEM. The experimental results show that the size of micelles is polydispersed, ranging from 100 to 500nm. The possible reason has been discussed.PS - b - PEO - b - PS triblock copolymers, micellization, self - assembly