Design Optimization and Dimensional Tolerance Improvement of Expanded Polypropylene (EPP) for Enhanced Automotive System Integration

Historically, EPP has required larger dimensional tolerances and much thicker cross-sections than solid plastics produced by injection molding, vacuum forming, and blow molding. This has proved challenging when attempting to incorporate EPP into a wider variety of automotive applications. JSP has developed multiple grades of EPP that achieve tolerances at thinner cross-sections, once considered difficult to attain. These grades expand the potential for automotive applications by combining the established benefits of EPP with improved dimensional precision. This tighter control enables advances in part design and performance, including reduced wall thicknesses, improved surface appearance, reduced weight, lower cost, part consolidation, and more efficient molding with an improved processing window, resulting in faster cycle times and reduced utility consumption. At the vehicle level, these improvements contribute to lighter overall weight for reduced carbon footprint, as well as increased cargo space by taking advantage of EPP parts with thinner cross-sections. Using current production equipment, testing was conducted on physical parts through real-time molding trials with measurements and analysis to confirm the improvements in tolerance and performance described above. Incorporating these findings early in the design phase of a given application will allow automotive engineers to fully leverage these benefits, ensuring optimal part integration, system-level performance, and alignment with corporate sustainability goals.