胶体晶体剪切模量的影响因素

摘要

利用自行搭建的扭转共振谱仪，研究了不同粒子体系胶体晶体在不同体积分数下的剪切模量，利用反射光谱测量了相应的晶体结构及内部孔洞等参数。结果表明，同一粒子体系的剪切模量均随体积分数的增加而增大；而对于同样的粒子数密度，不同粒子体系的剪切模量随体系内部孔洞所占比例增加呈增大趋势。对实验结果的分析及与理论分析的对比表明，决定胶体晶体剪切模量大小的主要因素是胶体晶体中粒子的最近邻间距，从而统一解释了体积分数和内部孔洞对胶体晶体剪切模量的影响。%Home-made torsional resonance spectroscopy was used to study the shear modulus of colloidal crys-tals formed by different particles at different volume fractions, while reflection spectrum was used to measure the corresponding crystal structure and internal voids etc. at the same time. The results indicate that shear modulus increases with volume fractions for colloidal crystals formed by same particles. And for colloidal crys-tals formed by different particles, the shear modulus has a tendency to increase with the increase of the fraction of internal voids for the same particle number density. Further analysis of the experimental results and the comparison with the theoretical analysis shows that the main factor influencing the shear modulus is the nearest interparticle distance, which explains the experimental findings.