Durability of Polypropylene Films in the Aspect of Petrochemical Product Safety for Packaging Materials Design

Petrochemical products face challenges under extreme conditions like high temperatures, UV radiation, and humidity, which accelerate the aging of polypropylene (PP) films and degrade their mechanical properties. This increases the risk of material failure, potentially leading to petrochemical leaks and posing ecological and safety hazards. This study focuses on the aging behavior of PP films, aiming to understand how environmental factors contribute to their degradation and exploring design solutions that can mitigate these risks and improve material durability. Thermogravimetric analysis and differential scanning calorimetry were employed to analyze the thermal stability of PP films under high-temperature conditions. The results show that the mass loss of modified PP materials was less than 10% at 500°C, while the decomposition temperature of multilayer composite PP materials was significantly higher than that of traditional single-layer PP materials. Furthermore, dynamic mechanical analysis (DMA) and impact tests were conducted to assess the brittleness of PP films in low-temperature environments. It was found that the impact strength of single-layer PP materials decreased by 75% at -100°C, whereas the modified PP materials maintained relatively stable impact performance. Hygrothermal aging and UV aging tests demonstrated that the tensile strength of multilayer composite PP materials decreased by only 16.3% after 1000 h of aging, and the increase in surface roughness was controlled within 0.78 μm, significantly outperforming single-layer materials. In the moisture and permeability tests, the water vapor transmission rate (WVTR) of the composite PP sealing structure was 0.18 g/m²·day, and the oxygen transmission rate (OTR) was 3.5 cm³/m²·day, showing superior performance compared to other sealing structures. By optimizing the material structure design and introducing composite sealing technology, this study significantly enhances the overall performance of PP packaging materials under extreme conditions, providing reliable protection for the safe storage and transportation of petrochemical products.