Interplay Between Blowing Agent and Nucleating Agent: Effect of Content Variation on Nucleation Efficiency and Cell Structure

ABSTRACT In this work, the effects of the interaction between the blowing and nucleating agent content on nucleation efficiency and cell structure were investigated, the growth process of the cells was observed using visualization equipment, and the nucleation process was fitted. The results demonstrated that the addition of ZIF‐8 nucleating agent at low blowing agent content (1.5 wt.%) significantly increased the cell density from 5.61 × 10 3 to 2.80 × 10 5 cells/cm 3 , and the cell size decreased from 372.6 to 86.2 μm. At high blowing agent content (4.5 wt.%), the nucleating agent addition resulted in only a modest increase in cell density, from 2.98 × 10 6 to 6.61 × 10 6 cells/cm 3 . The reduction in cell size was also less pronounced, decreasing from 48.65 to 32.49 μm. Simultaneously, foam samples were prepared using the core‐back technology for engineering verification, which exhibits excellent consistency with the visualization observations. Additionally, these results also revealed that the gas concentration was a key factor governing cell nucleation when the nucleating agent content was low. However, the heterogeneous nucleation mechanism played a dominant role under high nucleating agent content conditions, significantly reducing the nucleation energy barrier to enhance nucleation efficiency.