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The amphiphilic block copolymer has a wide range of uses in many fields, such as in the selective solvent may be formed micelles, can be used as an emulsifier, suspension polymerization stabilizers, crystallization modifier. The block copolymer is usually by \The branched structure of the polymer because of its unique structure, compared with the linear polymer, it is difficult to intermolecular entanglement occurs and therefore has a good solubility, low melting point and the viscosity of the solution and lower mechanical properties. In this thesis, the electron transfer catalyst atom transfer radical polymerization (AGET ATRP) and self-condensing vinyl polymerization (SCVP) technology combined to prepare amphiphilic block copolymer of a hyperbranched structure; same time, the use of reversible addition - fragmentation chain transfer (RAFT) polymerization responsive block copolymers. Research and performance of these materials. Specific work are summarized below: (1) By the method of combining of the the the AGET ATRP and SCVP technology, chosen with bromine end and a double bond in compound (BIEM) the two may initiator (inimer), synthetic water-soluble branched poly A methacrylic acid, N, N'-dimethylaminoethyl methacrylate (PDMAEMA). And azo-containing phenyl groups monomer (AzoMMA), as the second monomer synthesis branched polymer PDMAEMA-b-PAzoMMA polymerization behavior are \Of the obtained amphiphilic block copolymers photosensitivity, temperature sensitivity, and pH-responsive study found that photoisomerization behavior shows good regularity. We also use PDMAEMA-b-PAzoMMA drug load, investigated drug release behavior, the results showed that the drug release rate of the polymer structure, temperature, light and pH values. (2) α-dithio naphthoates isobutyronitrile ester (CPDN) RAFT agent, AIBN as initiator, in the anisole solution RAFT polymerization, triple sensitivity block copolymer was synthesized PDMAEMA-b -PAzoMMA-b-PHEMA. Using proton nuclear magnetic resonance spectroscopy (1H NMR) and gel permeation chromatography (GPC) to characterize the structure of the polymer. UV test results show that the lower critical temperature (LCST) of the copolymer solution is increased with the decrease of the pH value; the copolymer solution in THF and DMF photoisomerization rate size and PAzoMMA is homopolymer same; in aqueous solution photoinduced isomerization rate slows and decreases with increasing pH value; THF, DMF, and the water temperature rises will photoisomerization rate of the copolymer solution to speed up. The surface tension and the fluorescence intensity will change with the temperature, light and pH changes. We also by dynamic light scattering (DLS) and transmission electron microscopy (TEM) testing methods to examine the relationship between temperature, light and pH value of the self-assembly of the copolymer solution and the fluorescence emission intensity change. From the results, the change in intensity of fluorescence emission with the self-assembly of the polymer in the aqueous solution does exist necessarily linked.
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