The adsorption of partial hydrolyzed polyacrylamide (PHPA) on aluminum magnesium hydroxide (AMH) possessing permanent positive charges and effects of degree of hydrolysis(α)

pH

ionic strength and temperature have been studied. The presence of mutilayer adsorption of PHPA on AMH is found

and the amount of adsorption (A) decreases with increasing α of PHPA. With increasing pH the A of PHPA with lower α such as sample PHPA1 (α=2.4%) increases and however the A of PHPA with higher α such as samples PHPA2(α=10.8%)and PHPA3(α=41.2%)decrease.The presence of NaCl may reduce the A of PHPAl but may raise the A of PHPA2.The increase of temperature may raise the A of PHPA

which indicates that the adsorption processes studied are endothermic.The mechanism of adsorption has been discussed in the paper.According to the experimental results

in is inferred that the adsorptive force between flexible polymer moleculae and adsorbent has a optimum range in which the amount of adsorption is maximum.When the adsorptive force is too strong

the amount of adsorption will be lower because the sdsorbed flexible moleculae mey be spreed.Of course

when the adsorptive force is too weak

the amount of adsorption will be lower also.