含铅聚合物微凝胶与硫化氢反应前后在良溶剂中的分子扩散行为

Studies on Molecular Diffusion Behavior Before and After Reaction Between Pb￣(2+) -Containing Microgel and H_2S in a Good Solvent

用溶液聚合法制备出轻度交联的含铅微凝胶，用光子相关光谱技术测定其在良溶剂中与Ｈ_２Ｓ反应前、后的扩散行为，由外推法得到在浓度无限稀时的分子扩散系数，给出微凝胶的流体力学半径。结果表明：相同量的含铅微凝胶在不同的初始浓度下与Ｈ_２Ｓ反应，生成含ＰｂＳ纳米微粒的凝胶；但其体积增大不同，这说明Ｈ_２Ｓ与含铅微凝胶的反应既可以在分子内也可以在分子间进行，分子间的反应使含硫化铅微凝胶扩散系数随浓度的变化曲线的线性范围变小．

A new 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 H2S in 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 H2S reacted not only within one microgel particle, but also between the microgel particles, The linear relationship range of D-C curve decreased because of the connection betweenPbS-containing microgel particles.