Study on properties of BF/PP composites and plastic parts manufacturing by mold opening foaming injection molding

Basalt fiber (BF), as an emerging natural and environmental-friendly material, possesses a broad application prospect. Herein, lightweight and strong BF reinforced polypropylene (BF/PP) composite foams were successfully prepared using mold opening foam injection molding (MOFIM) technology. It was revealed that the combination of increased crystallinity and enhanced rheological behavior in turn contributes to the improved foaming behavior of 20%BF/PP, which reduces the cell size of PP to 36.38 & mu;m and boosts the cell density by a factor of 2 under an expansion ratio of 1.2. The improvement effect of BF on cell structure is more obvious at higher expansion ratio. This fine and dense cell structure further augments the impact performance and flexural modulus of BF/PP composite foams. Compared to pure PP, 20%BF/PP composite foams experienced an increasement of impact performance, which is increased by 68.8% to 2.7 kJ/m2, and its flexural modulus also elevated significantly by 224.8% to 2440.25 GPa. Due to its excellent weight reduction effect, the specific impact strength and specific flexural modulus remain at much higher levels than those of PP foam. This indicates that BF and MOFIM technique successfully prepared a ductile material with excellent impact resistance, modulus and thermal insulation properties.