The Outdoor Aging Properties of Polypropylene/Mica Composite

Abstract

In this paper, In this paper, polypropylene / mica composites were prepared by blending, using polypropylene (PP) as matrix, mica as filler. In order to study the anti-aging properties of polypropylene / mica composite materials, the above polypropylene / mica composite materials were placed outside to study the influence of natural aging time on the anti-aging properties and to explore the natural aging mechanism of polypropylene / mica composites. Natural aging research results show that:with the extension of the natural aging time the surface of materials will appear cracks and sheddings. The trends of tensile strength reduce at first, then increase and then decrease; the notched impact toughness values show fluctuating in the early aging, then an increase following and then decreasing.The increase of mica content are good for maintaining the mechanical properties of PP / mica composite, PP-g-MAH helps to maintain the tensile strength, while toughening POE-g-MAH will weaken the anti-aging properties of polypropylene / mica composite materials.

Photoaging and Fire Performance of Polypropylene Containing Melamine Phosphate

“…The bond energy of P−O is 410 kJ/ mol, which is similar to the energy of ultraviolet light (299− 419 kJ/mol) and lower than the energy of PO. 26 Therefore, P−O bonds are more likely to be broken under UVA light irradiation to decompose into ammonium dihydrogen phosphate and ammonium ions, which accelerates the photoaging process of PP. However, the triazine rings in MPP will first absorb some UVA light energy and protect P−O bonds from breaking in the early stages of photoaging, Scheme 2 shows the aging mechanism of PP and PP/MPP.…”

“…Similar to APP, the chain of MPP contains a large number of PO and P–O bonds. The bond energy of P–O is 410 kJ/mol, which is similar to the energy of ultraviolet light (299–419 kJ/mol) and lower than the energy of PO . Therefore, P–O bonds are more likely to be broken under UVA light irradiation to decompose into ammonium dihydrogen phosphate and ammonium ions, which accelerates the photoaging process of PP.…”