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Maleic anhydride , 1,6 - hexanediol and polyethylene glycol monomethyl ether as the raw material to p-toluenesulfonic acid as a catalyst , by the one-step and two - step method two different pathways were synthesized MePEG- b-Polyester amphiphilic block copolymers . Step process, first of all , the solution polycondensation method using toluene as a solvent and as a catalyst , p-toluenesulfonic , maleic acid anhydride , and 1,6 - hexanediol synthesis of raw material monomers of a certain molecular weight polyester , and secondly, the use of acetic acid on polyesters capped, their activation, and finally thionyl chloride , polyethylene glycol monomethyl ether and capped activated polyester polycondensation reaction to obtain a double bond-containing amphiphilic block copolymer , and by GPC and IR . its characterization . The results show that the two-step method is obtained in the amphiphilic block copolymer is a multi-component , endcapped unactivated yield than the yield is low in the activation , however, more complex components of the activation of the product with thionyl chloride , Therefore, the two-step method to the thionyl do activation is less than ideal. Step process, and investigated the solution polymerization, melt polymerization, the feeding mode , feed ratio , and reaction time on the polymer molecular weight and its distribution , the results show that the step solution polymerization method to obtain the molecular weight distribution is relatively narrow . Amphiphilic block copolymer self-assembly behavior in different solution further study , the effects of solvent , mixing time , the composition of the polymer and polymer in the organic solvent concentration on the micellization behavior of polymer self-assembly through were observed under transmission electron microscope (TEM) , and dynamic light scattering (DLS) show that the aqueous solution in N, N- dimethylformamide , and tetrahydrofuran as a solvent , the self-assembled amphiphilic block copolymers can be obtained having a core - shell structure of the nano- micelles , and acetone , and 1,4 - dioxane is obtained concentric core-shell is not in the micelles , the stirring time increases the micellar particle size gradually decreases , the polyester molecular weight increases gradually decreases the particle size of the micelles tablets diameter increases, the distribution of concentration in the organic solvent increases, the particle size and particle size distribution is gradually increased . In short,
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