Quantitative characterization of dispersion of carbon black masterbatch

Polypropylene(PP)/ carbon black(CB) films were prepared via melt blending-masterbatch dilution method,assisted by a high-efficiency dynamic mixer.The thermogravimetric analysis(TGA) and color difference(CD) mettod,a potential on-line measurement new method,were employed to characterize the dispersion of CB particles in PP matrix.TGA results show that the CB particles have a good dispersion when its mass concentration is 2.2%.When the mass concentration comes up to 3.3%,the dispersion of CB is slightly worse,however,the curves of TGA are coincident well.The standard CD and CD between every two samples both indicate that CB particles are well dispersed and uniformly distributed.The testing method of skewness-kurtosis was employed to test the normal distribution of color difference values and its significance.It shows that the color difference values approximately follow normal distribution and there exists no significant difference between them.Besides,based on the relationship between CD and gray scale,the achieved gray scale of the films is 4.68.