Numerical calculation of temperature distribution and influence on foaming quality of foamed polypropylene materials

Abstract During the preparation of foamed polypropylene (PP) materials through injection molding, temperature distribution is a critical factor influencing the quality of the foaming process. To tackle this issue, an empirical formula for temperature distribution was developed using Fourier's law as a foundation. The temperature distributions under steady‐state and non‐steady‐state conditions were calculated, simulated, and thoroughly analyzed to evaluate their impact on the foaming quality. The findings reveal that, under both steady‐state and non‐steady‐state conditions, the theoretical temperature calculations demonstrate a consistent decline from the central region to the edge of the isothermal surface, with values ranging between 463 and 311.9 K. The simulation outcomes align closely with the theoretical predictions and demonstrate strong reproducibility. However, uneven temperature distribution caused an initial improvement in foaming quality, followed by subsequent deterioration. Notably, position c (between the center and the edge, near the edge) exhibited the highest foaming quality, achieving a cell density of 7.65 × 10 9 cells/cm 3 and an average cell diameter of 52.5 μm. The relevant research findings offer valuable insights for optimizing the foaming quality of foamed PP materials, providing a theoretical foundation for the design of temperature control systems and the optimization of process parameters in industrial production. Highlights Proposed a method for calculating the temperature distribution of materials. The temperature gradually decreases from the center to the edge. The simulation results are consistent with the theoretical calculation results. On the same isothermal surface, position (c) has the best foam quality.