Process-informed finite element modeling of PET zippers: A multiscale framework with velocity-dependent contact and experimental validation

Polymer zippers are widely used in consumer and industrial products, yet their performance is governed by complex contact-dominated interactions between molded teeth, sliders, and stitched joints, which are difficult to assess prior to manufacturing. This study develops a process-informed finite element framework that links polymer manufacturing and assembly parameters to product-level mechanical performance of PET zippers. The framework integrates strain-energy-guided adaptive mesh refinement, a velocity-dependent friction formulation tailored to slider-tooth nonlinear interactions, and a multiscale representation of molded teeth and stitched connections. Experimental testing supports the predictive capability of the model, with relative deviations within 2.40%, while computational time is reduced by 26.92% compared with uniform meshing. A parametric study indicates that small geometric deviations can noticeably affect interlocking efficiency and global load transfer. Overall, the proposed framework provides a practical virtual verification tool for high-performance zipper product development and supports simulation-assisted design of process-sensitive polymer zipper assemblies.