Dendrimer's Endgroup Modification And Study On Character As Phase Transfer Agent Of Dyes

Dendrimer are a relatively new class of materials with unique molecular architectures and dimensions in comparison to traditional linear polymers. Generally dendrimer's specialties are to design the molecular size, shape and functional group at the molecular level. According to its own specialties, studying systematacially the molecular structure and performance, developing the function macromolecule with new-type terminal group is an important research direction. The surface terminal group can carry on function transform. There are amido, hydroxyl, carboxyl, ester base, alkyl, acylamino group, metal chelate compound etc that have already been reported at present. Because there are active sites among the center and inside of dendrimers. Those make this kind of macromolecule have well enough application prospects in drug deliver, catalyst carrier, gene therapy, metal millimicron composite and membrane material etc. The thesis has introduced briefly the structure and performance of dendrimers, and has reviewed the newest progress in synthesizing and functional of dendrmers systematically. According to methods in the literatures, endgroup alkylated dendrimer with ethylenediamine as core has been synthesized by means of covalent bond or electrostatic self-assemble. The molecular structures of the product have been characterized by means of element analysis, infrared spectrum(IR). The validity of the molecular structure of dendrimer was proved tomatch with the designing target molecular. According to its own specialties of dendrimer with alkyl end group, its performance as phase transfer translating dyes from water phase into organic phase is explored. Guest molecule was transfered into organic phase successfully by dendrimers terminated in alkyl groups with covalent bond, for example methyl orange as guest molecule. With the concentration of dendrimer, generation of dendrimer and acid value of water phase increasing, extraction yield of methyl orange adds. Corresponding PAMAM(A) 1.0G, 2.0G and 3.0G, theirs maximal extraction yield is 19.81%,40.57%,87.11%, without adjusting pH value of water phase. In the condition the water phase pH=2.56, theirs maximal extraction yield is 74.22%,89.32%,93.97%. We have chosen three kinds of hydrophilic dyes, Methyl Orange, Congo Rose and Acid Orange as guest molecules, electrostaic self-assembled dentrimer as the host molecule to study dendrimer's performance as phase transfer. The results have showed that, there have been highest extraction yields in the same generation while enhancing the mass concentration of dodecanoic. Methyl Orange, Acid Orange and Congo red as the guest molecules, the highest extration yields are 68.46% ,59.64%, 92.61% corresponding PAMAM 3.0G. When the concentrations of the dyes and the mass concentration of dodecanoic are settled, the extraction yields of dyes are enhancing while increasing the concentrations and the generations of the dendrimer.