| In the rapidly developing field of biomaterials, pharmaceutical, biochemistry and polymer science, amphiphilic block copolymers have exhibited various interesting properties such as surface activity, aggregate formation and so on, which have made them as potential candidates of advanced materials formation and engineering applications.A novel type of amphiphilic tri-block copolymers with both pH and temperature sensitiveness: poly(ethylene glycol)-poly (dimethylamino ethyl methacrylate)-poly (ε-caprolactone) (PEG-PDMAEMA-PCL) was synthesized via sequential oxyanionic polymerization of macro-molecular: PEG, with a hydroxyl at one end, and dimethylamino ethyl methacrylate (DMAEMA) andε-caprolactone (ε-CL), with the potassium naphthalene as the initiator. While PDMAEMA-PCL was prepared using the same materials: DMAEMA,ε-CL, initiated by potassium di (trimethylsilicon) amide ([(CH3)3Si]2N-K+). The structures of the polymers were confirmed by 1H NMR spectroscopy and gel permeation chromatography (GPC). The self-assembly behavior of the block copolymers in aqueous solution was studied by using dynamic light scattering (DLS) and transmission electron microscopy (TEM). It shows that the PDMAEMA segment is not only affect the size of micelles and also plays an important role: responding to the pH and temperature changing of the aqueous solutions, while the crystalline corn formed by PCL contributes to the changing of the size and the morphology of the micelles too. If the factors of aqueous solutions varied, the size and distribution of micelles will be changed. It made the copolymers more designable for template.After studied the self-assembly behavior of the copolymers in aqueous solutions, the changes of micelles responding to the varying of pH and temperature was gained. And we used this changing rule in the synthesis of hollow CuO sphere: studied the effection of precipitator dose, the type and the block ratio in the copolymer.
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