基于后向散射的高浓度纳米颗粒粒度分布测量方法研究

Research on measurement method of size distribution for high-concentration nano-particles based on back scattering

传统的动态光散射法通常采集侧向散射进行纳米颗粒粒度分布的测量,由于多次散射的影响,利用侧向散射不能准确测量高浓度样品的颗粒粒度分布。针对该问题,对后向散射测量方法进行了研究,在实验基础上提出了后向散射最佳光程的判断准则。在不同样品浓度下,用侧向散射和后向散射方法对标称粒径分别为110 nm、220 nm的聚苯乙烯乳胶球颗粒进行了测量。实验结果表明,对于高浓度的待测样品,后向散射测量方法通过自适应调整光程,在最优光程处进行测量,能够有效得到高浓度纳米颗粒的粒径及粒度分布,测量结果相对误差为2.72%。

The traditional dynamic light scattering method usually collects the lateral scattering to measure the size distribution of nano-particles.Because of the influence of multiple scattering,the particle size distribution of high-concentration samples cannot be accurately measured by lateral scattering.Aiming at the problem,the back scattering measurement method was studied,and the criterion of the optimal optical path of back scattering was proposed based on the experiment.At different sample concentrations,the polystyrene latex sphere particles with a nominal particle size of 110 nm and 220 nm were measured by lateral scattering method and back scattering method,respectively.The experimental results show that the back scattering method can self-adaptively adjust the optical path for high-concentration samples,and the measurement can be carried out at the optimal optical path to effectively obtain the particle size and the size distribution of high-concentration nano-particles,and the relative error of measurement results is 2.72%.