Dentritic polymers which combine the temperature—and pH—sensitivities wel'e synthesized．At first

polyamidoamine(PAMAM)dendrimers with generations 1 to 3 wele synthesized by reaction of ethylenediamine with methyl acrylate

then polymers synthesized were acylated by chloroacetyl chloride to obtain PAMAM-C1

which can act as a maeminitiator for further synthesizing functional polymers having both pH—and thermo—sensitives．For fulfiUing this goal

polymers with dentritic PAMAM as the core and different average length of poly(N

N-dimethylaminoethyl methacrylate)(PDMAEMA)were synthesized by atom transfer radical polymerization(ATRP)． Their maeromoleeular structures were characterized by FTIR．1H—NMR and particle size analyses．Their aqueous solutions were studied by UV spectroscopy for understanding their thermo—and pH-sensitivities．The results showed that these dentritic polymers exhibit clearly thermo—-and pH··respondings in accordance with the change of the environment．Using ehlorambucil(CLB)as a model drug

the controlled drug release behavior of the polymers having different average length of PDMAEMA was studied．The results indicated that the rate of the drug release can be effectively controlled by pH values．