Quantitative evaluation of nanoparticle dispersion based on modeling methods and image analysis: A case study on nano-Sb2O3 filled Poly (butylene terephthalate) composites

摘要

The dispersion state of filler in polymer-matrix composites plays a significant role in determining the performance of nanocomposites. Thus, the quantification of dispersion analysis for inclusions in polymer composites is crucial. In this paper, the robust methods for the quantitative assessment of dispersion are developed. The methods are based on the modeling evaluation and direct analysis of scanning electron microscopy micrographs using binary image technology. The dispersion degree in polymer nanocomposites reinforced with inorganic nanoparticles is calculated by modeling method. In addition, the effect of dispersion on the tensile modulus of nanocomposites is analyzed by modeling method. To further quantify the dispersion of nanoparticles, the mean distance value between nanoparticles is measured. The dispersion index D is defined as the probability of inclusion particles free-path spacing, according to the frequency distribution of particle spacing data. The dispersion states of different samples are compared to examine the availability of the analysis methods to various dispersion conditions such as the effect of aggregation, agglomeration, cluster distribution, and surface treatment of nanoparticles. Besides, another modeling methodology is established based on inter-particle distance of the nanocomposites. In this model, the dispersion of the nanoparticles is assessed by comparing the inter-particle distance with the theoretical value assuming a perfect dispersion. In the case of nano-Sb2O3 filled Poly (butylene terephthalate) composites, the composites with different dispersion and distribution characteristics were prepared. And the microstructures of these composites are also employed to access the applicability and functionality of the analysis methods.