Synthesis, Characterization And Properties Of Methyl β-cyclodextrin Graft Copolymers

Cyclodextrins are cyclic oligoamyloses,consisting of 6(α),7(β),8(γ)or 12 (α-1,4)-linked a-D-glucopyranose units. Because of their hydrophobic cavity and hydrophilic surface, they can encapsulate small lipophilic molecules by non-covalent bond. They have been used in molecule recognition, stationary phases of chromatography, catalysis, solubilization, control release of drugs, biotechnology and so on. The natural CDs, in particular β-CD, have limited solubility in water. So the applications of CDs in many fields are limited. Cyclodextrin can be also incorporated into polymer matrix and can obtain the special properties, because polymers can offer mechanical support and increase their chemical stabilities, while the hydrophobic cavity may provide special reactivity.This paper reports the synthesis and properties of methyl p-cyclodextrin graft poly (N-isopropyl acrylamide ) (M-β-CD-g-PNIPA) and methyl β-cyclodextrin graft polyacrylamide( M-β-CD-g-PAM) using potassium persulfate (KPS) and N,N,N',N'-tetra-methyl ethylene diamine(TMEDA) as redox initiator in aqueous solution. So our research work was conducted from the two aspects as following:1. methyl p-cyclodextrin graft poly(N-isopropyl acrylamide) (M-β-CD-g-PNIPAM)In this part, we synthesized M-β-CD-g-PNIPA copolymer in aqueous solution using M-β-CD and N-isopropyl acrylamide (NIPA) and KPS-TMEDA as initiator. The chemical structure of M-β-CD-g-PNIPA copolymer was confirmed by IR, ~1H-NMR and elemental analysis. The results all show that poly(N-isopropyl acrylamide) chains are grafted on M-β-CD. Thermal stability of M-β-CD-g-PNIPA copolymer was determined by TGA. Then the solution properties of the M-β-CD-g-PNIPA were studied by spectrophotometer and Ubbelohde viscosimeter.