Self-association of a thermo-sensitive copolymer with transition temperature coincident to the normal body temperature of human beings in aqueous solution

A special thermosensitive copolymer, which has a lower critical solubility temperature near human body temperature of 37 degreesC in aqueous solution, has been prepared successfully by introducing an appropriate quantity of N-isopropylmethacrylamide monomer randomly into the poly(N-isopropylacrylamide) main chain. The self-association behavior of the copolymer in water has been investigated by Dynamic Laser Light Scattering (DLLS) and viscosity method. When the concentration of the solution is higher than the calculated dynamic contact concentration from cluster theory, the effect of the concentration on the distribution of the hydrodynamic radius from the DLLS results has been discussed fully.