MULTIFRACTAL ANALYSIS AND MICROMORPHOLOGIES OF RADIATION SYNTHESIZED HYDROGEL POLYMERS

Polyacrylamide (PAM) and poly sodium acrylate (PNaA) homopolymer hydro gels and five kinds of P(AM-NaA) copolymer hydrogels with different mo nomer molar ratios AM/NaA were synthesized by Co-60-gamma ray radiatio n polymerization in aqueous solutions. The micromorphologies of these hydrogel polymer samples were observed by a scanning election microsco pe (SEM). From the interaction between the chain segments of polymers, it is qualitatively expounded that the cross-linking network structur e of hydrogel polymers displayed successively the thicker framework ne twork - incomplete bubble film network - dense network with the increa se of NaA units in the hydrogel polymer chains. The non-homogeneity an d complexity of micro network distribution of hydrogel polymers were e lucidated by the multifractal theory. The results show that the multif ractal spectrum, singular index alpha and Hausdorff dimension D-0 can quantitatively characterize the non-homogeneity and the width of netwo rk distribution of hydrogel homopolymers and copolymers.