Effect of salt solutions on chain structure of partially hydrolyzed polyacrylamide

The effect of salt solutions (NaCl, Na2SO4 and CaCl2) on the conformational properties of partially hydrolyzed polyacrylamide (HPAM) was investigated by using static laser light scattering (SLLS). The special interaction between CaCl2 solution and HPAM was also researched. Experimental results show that the chain structure of HPAM is interrelated with the charge density, the kind and the concentration of salt solutions. The mean-square radius of gyration (Rz) and the second virial coefficient (A2) of HPAM decrease with increasing concentration of salt solutions, and the salt effect tends towards the maximum when the concentration of salt solution is increased to some amount.