Synthesis of high molecular weight partially hydrolyzed polyacrylamide and investigation on its properties

A continuous process for the polymerization of acrylamide and hydrolysis of functional groups in alkaline condition has been carried out. It was found that acrylamide A may be polymerized and hydrolyzed in a single consequential step, whereby, both degrees of polymerization and hydrolysis can be carefully controlled. The hydrolysis of 7 polyacrylamide up to 10 and 60% degrees was facilitated in suitable amount of different alkalines. The degree of hydrolysis of samples was determined by a back titration method. We have found that sodium carbonate as an hydrolyzing agent, also acts as a retarder and its addition to polymerization solution reduces the rate of polymerization reaction. The measured molecular weight of samples shows that we have reached a high molecular weight (about 12 million) and excellent water solubility. Another interesting result obtained is that the copolymer solutions showed a non-newtonian shear thinning behaviour. On the other hand, the associative behaviour is observed between the samples.