| Double hydrophilic block copolymers are a new type of amphiphilic block copolymers with increasing attention being paid to by scientists in material science, pharmacy, biochemistry and polymer science. Here double hydrophilic block copolymers with both pH and temperature sensitiveness were synthesized. By adjustment of solution conditions like pH, temperature etc, micelles were successfully prepared with organic solvents obviated.Well-defined AB double hydrophilic block copolymers of poly (ethylene glycol) -b-poly [2-(dimethylamino) ethyl methacrylate] (PEG-b-PDMAEMA) were synthesized via anionic polymerization using potassium tertbutoxide and potassium bis (trimethylsilyl) amide ([(CH3)3Si] NK) as the initiator respectively. Dynamic light scattering (DLS), 1H-NMR and transmission electron microscopy (TEM) have been used to study the associative behavior of these copolymers in water as a function of block ratio, concentration, pH and temperature. Primary study of the effect of multivalent ions of both anionic and cationic on the association behavior was also carried out for better understanding of the micellization process. Examination of the association behavior revealed that an appropriate block ratio of the two constituting blocks is the precondition to form micelles. With extraordinary sensitiveness to concentration, temperature and pH, the micelle system of these copolymers can be finely tuned and has great prospect in many fields as in drug delivery systems.The interaction of PEG-b-PDMAEMA copolymers with Cu2+ ions was studied. It was found that Cu2+ can induce the copolymer to form micelles that are invulnerable to temperature variation as long as the temperature is lower than 60℃. The micelles formed can serve as metal hydration reaction nanoreactors and that for preparing metal nanoparticles. Studies were conducted on the catalytic ability of the Cu2+-polymer complex in oxidation reaction ofβ-isophorone. Ideal results were concluded.
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