Lightweight and tough PVDF foams via high‐pressure foam injection molding with core‐back operation

Polyvinylidene fluoride (PVDF) foams prepared by batch foaming have been intensively studied, but it still remains a challenge to fabricate high‐performance PVDF foams for structural applications. Herein, by adding polymethyl methacrylate (PMMA) as the minor component, the blend foams were successfully fabricated using supercritical carbon dioxide (CO2) as a green blowing agent via foam injection molding (FIM) with core‐back operation. The added PMMA could reduce the crystal size of PVDF. Owing to fine cellular structure and small crystal sizes, the injection‐molded blend microcellular foams exhibited superior mechanical properties. Especially, the elongation at break and specific breaking energy of the blend foam with 40% void fraction were separately increased by 184% and 297% compared to that of the PVDF foam. These findings revealed that the lightweight microcellular PVDF foams with improved toughness could be manufactured by the scale‐up and efficient FIM technology, which showed a promising future in automotive and other structural applications. In this study, by adding PMMA as the minor component, the cellular structures, elongation at break and specific breaking energy of injection‐molded PVDF foams were greatly improved.