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Aging behavior of nano-CaCO3-modified polypropylene nonwoven fabric composites

Nano-CaCO3-modified polypropylene (PP) nonwoven fabric composite is widely used as the filter material which could overcome the poor lightfastness and low weight of the pure one, while its aging performances would be influenced. In this article, the aging behavior of the nano-CaCO3-modified PP nonwoven fabric composite was investigated. At first, the difference between untreated and CaCO3-modified PP nonwoven fabric was analyzed by scanning electron microscopy, thermogravimetric/differential thermal analysis, and X-ray diffraction. Then the aging behaviors of these two PP nonwoven fabrics were studied in detail. The results showed that the PP nonwoven fabric exhibited good acid corrosion resistance. On the contrary, acid corrosion resistance of the modified PP nonwoven fabric was poor; although its weight and strength didn’t change under weak acid condition, its weight and strength loss both increased obviously under medium and strong acid condition with the prolongation of corrosion time. Due to the ultraviolet (UV) energy dissipation of nano-CaCO3 particles, the UV aging resistance of the modified PP nonwoven fabric was improved, and the compound UV aging under weak acid condition was also superior to that of the untreated PP fabric. This article will provide experimental and theoretical base for the structural regulation of CaCO3-modified PP fibers.