INVERSE MICROEMULSION POLYMERIZATION OF ACRYLAMIDE IN THE PRESENCE OFHEXAMETHYLENETETRAMINE

The inverse microemulsion polymerization of acrylamide is retarded in the presence of hexamethylenetetramine. The retardation effect of a gi ven hexamethylenetetramine concentration on the kinetics of the polyme rization of acrylamide depends on the pH of compartmentalized water dr oplets. For non-crosslinked polymer particles the polymer particle dia meter for a given composition of the inverse microemulsion increases i n the presence of hexamethylenetetramine, while the relative molecular mass (molecular weight) of the polymer decreases. Depending on the pH value of the compartmentalized water droplets polymer particles with different crosslinking degree (of different swelling index) were obtai ned. The kinetics of polymerization and the polymer particle character istics are discussed with respect to the hexamethylenetetramine effect on the stability of dispersed particles in an inverse microemulsion p rior to and during the polymerization and in terms of the effect of '' in situ'' formed hexamethylenetetramine decomposition products and of their reactions with acrylamide and/or acrylamide structural units in the polymer.