Synthesis And Chiral Separation Of Chiral Polymer Nanoparticles With 1, 2:3, 4-Di-O-isopropylidene-D-galactopyranose Group

In this thesis, 6-O-p-vinylbenzyl-1,2:3,4-Di-O-isopropylidene-D-galactopyranose (VBPG) was selected as the monomer: (1) various cross-linked chiral nanoparticles were prepared by RAFT miniemulsion polymerization with different amounts of cross-linker, and (2) grafting chiral P(VBPG) chains to the silica surface by the combination ATRP and "click" chemistry method, to obtain chiral hybrid silica nanoparticles. And then studied the chiral separation and other related properties of the two kinds of nanoparticles.The results were shown as follows:1. VBPG was selected as the monomer, divinyl benzene (DVB) as the cross-linker if used, 2,2'-azobisisobutyronitrile (AIBN) as the initiator, P(VBPG) (Mn,GPC = 6200 g/mol, Mw/Mn = 1.12) as the Macro-RAFT agent, n-hexadecane (HD) as the co-emulsifier, toluene as the solvent, sodium dodecyl benzene sulfonate as the emulsifier for the RAFT miniemulsion polymerization. Firstly, the kinetics of RAFT miniemulsion polymerization was studied without cross-linker. The results showed P(VBPG) molecular weight increased with conversion and the polydispersity index kept narrow (PDI = 1.12-1.50), indicating a"living"/control polymerization process. Secondly, effects of the amount of the cross-linker on the properties of the cross-linked nanoparticles were studied. The results showed that the diameter of the obtained nanoparticles increased first and then decreased with the amount of the cross-linker in the range of 51-130 nm. Lastly, chiral separation of the nanoparticles for D,L-arabinose, (±)-3-amino-1,2-propanediol was investigated. It was found that the chiral nanoparticles not only had good chiral separation ability but also could be reused.2. Three chiral P(VBPG)s with different molecular weights containing alkynyl end group were obtained using 2-bromo-isobutyrate-3-butyl acetylene (BEiB) as functional initiator via ATRP method. Then, the P(VBPG) chains were grafted onto the surfaces of silica nanoparticles with azide group via the "click" chemistry to prepare the chiral hybrid naoparticles. The ability of enantioselective recognition of the three organic/inorganic silica hybrid nanoparticles for tartaric acid and (±)-3-amino-1,2-propanediol was investigated. It was found that hybrid nanoparticles had good chiral separation ability. Finally, we investigated the chiral hybrid nanoparticles as the chiral stationary phases (CSPs) for high-performance liquid chromatography, it was found that the chiral hybrid nanoparticles in chromatography column as the fixity can reach the baseline separation of Mandelic Acid.