通过过滤及凝胶渗透色谱分离提纯木质素磺酸钠( NaLS) ; 利用静态光散射测定其绝对分子质量，并通过加盐的方法消除慢运动峰对测量的影响; 采用动态光散射测定不同温度下NaLS 分子的扩散系数．根据测定的扩散系数及绝对分子质量，使用Perrin 公式拟合计算不同温度下NaLS 分子的椭球结构．结果表明: 光散射法测得的NaLS 分子的绝对分子质量大于凝胶渗透色谱( GPC) 测定的相对分子质量，更接近于真实分子质量; 温度升高，NaLS 分子扩散系数增大，布朗运动加快; Pellin 公式拟合显示不同温度下NaLS 分子均为长短轴比7．5 以上的接近碟状的扁平椭球结构，该结构随着温度升高变扁．此外，结合已有木质素磺酸盐的结构研究结果，建立了不同温度下NaLS 分子的椭球模型．

First,sodium lignosulfonate ( NaLS) was purified and fractionated through filtering and gel chromatography. Next,the absolute molecular mass of NaLS was determined by means of the static light scattering,and enough salt was added to eliminate the influence of the slow mode on the determination. Then,the diffusion coefficients of NaLS molecules at different temperatures were measured by means of the dynamic light scattering. Based on the obtained absolute molecular mass and diffusion coefficients,the fitting calculation of the ellipsoid structures of NaLS molecules at different temperatures was carried out by using Perrin formula. The results show that the absolute molecular mass of NaLS obtained through the light scattering methods is larger than that measured via gel permeation chromatography ( GPC) and it is closer to its real molecular mass; and that,with the increase of the temperature,the diffusion coefficient of NaLS molecules increases,indicating that the Brownian motion is accelerated. Fitting results obtained through Perrin formula demonstrate that the structures of NaLS molecules at different temperatures are all disk-like oblate ellipsoids with ratios of the length of longer axis to that of shorter more than 7.5,and they become more oblate when the solution temperature increases. In addition,the ellipsoid models of NaLS molecules at different temperatures were constructed by combining the results in this paper with the existing ones in the literature.