Abstract: Anew kind of lightly crosslinking microgel containing lead ions was prepared by solution polymerization.The diffusion behavior, before and after reaction between the Pb²⁺ -containing microgel and H₂Sin a good solvent, was measured by means of Dynamic Light Scatttering separately.The diffusion coefficients of the microgels at infinite dilution concentration were obtained by extrapolation and hydrodynamic radii of the microgels were calculated with Stokes-Einstein equation.The results show that the volumes of PbS-containing microgel varied with the initial concentrations of Pb²⁺ containing microgel in reaction. It shows that H₂Sreacted not only within one microgel particle, but also between the microgel particles, The linear relationship range of D-Ccurve decreased because of the connection betweenPbS-containing microgel particles.

Key words: Photon correlation spectroscopy, Molecular diffusion coefficient, Lead ions-containing microgel (P-Pb), PbS-containing microgel(P-PbS), PbS ultrafine particle