Two kinds of β-cyclodextrin(β-CD)-acrylic monomers

β-CD-3-A and β-CD-6-A

carrying the acryl groups were synthesized relying on their reactivity of different hydroxyl groups in cyclodextrin. 13C-NMR spectra indicated that

for β-CD-3-A

acylation occurs at C-2 and C-3 positions of β-CD

and for β-CD-6-A

the acylation occurs at its C-2 and C-6 positions．Two functional hydrogels were synthesized by copolymerization of β-CD-3-A and β-CD-6-A with N

N-dimethylaminoethyl methacrylate (DMAEMA) using a redox initiator svstem in aqueous solutions．The hydrogels were characterized by FTIR and elementary analysis．The equilibrium swelling experiments show that the hydrogels possess pH-

ionic strength and thermo-sensitivities．However

due to the difference of monomer structures

the physical properties of the two hydmgels．especially their swelling behavior in response to the extemal stimuli

exhibit certain difference It is reasonable to assume that the structure of β-CD-3-A in its hydrogel is more favorable to initiate hydrophobic interactions between dimethylaminoethyl segments and hydmphobic caves in β-CD

as a result

reducing the hydmgel’s transition points．It can also be observed that the transition regions for both hydrogels shift to lower temperatures with the increase in contents of β-CD-3-A or β-CD-6-A．