A series of water-soluble macroinitiators derived from polyethyleneimine(HPEI) were used to initiate the SET-LRP of DMAEMA at 0℃ in aqueous solution. The polymers prepared were characterized by

1

H NMR

FT-IR and GPC. The effects of DMAEMA/H

2

O(v/v)on polymerization were studied and the optimum condition was given. The response behavior of star-shaped PDMAEMA (H-PDMAEMA)with different amounts of arms was studied by turbidimetry. The results showed that the process is a well-controlled living radical polymerization. With the increase of the arms

the LCSTs of H-PDMAEMA decreased

the thermo sensitive property of the copolymer can be magnified by the increasing arms.the LCSTs of H-PDMAEMA. The supramolecular hydrogel was constructed by blending H-PDMAEMA with partial hydrolyzed polyacrylamide (HPAM). The effects of H-PDMAEMA structure on the viscosity of HPAM aqueous solution were investigated. The results show that the H-PDMAEMA can improve the viscosity of HPAM aqueous solution; with the increasing arms of H-PDMAEMA

the viscosifying ability is improved; compared with HPAM

the HPAM/H-PDMAEMA supramolecular hydrogel solution system has excellent heat resistance. In a certain range of salt concentration and shear rate

the viscosity of HPAM/H-PDMAEMA is higher than that of HPAM solution.