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Recently, the issue of energy-saving and environmental protection has attracted enormous interest in developing polymeric composite foams. Fillers have been identified as major materials to tailor cellular structures and mechanical properties for single component thermoplastics. However, it is often difficult to achieve the desired effect due to the natural tendency of fillers. The study aims to provide a facile method for improving the dispersion and arrangement of filler phase based on in situ fibrillation. Polytetrafluoroethylene (PTFE) was used in the in situ fibrillated phase to promote the dispersion of talc throughout the polypropylene (PP) matrix for the ternary composite foams of PP/talc/PTFE. The mechanisms of PTFE fibrils and their effect were studied in terms of crystallization, rheology, foaming behavior, and mechanical properties. The results proved that a fibrillar network was formed

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Injection molding (IM) is one of the most essential forming methods for plastics. However, some potential risks which influence part quality may occur in the molding process. A non-return valve (NRV) is a major component on the screw head whose function is to seal during the injection process to prevent the backflow of the melt. The NRV will wear in this process and cause fluctuations in parameters and quality but the wear states of NRVs cannot be monitored without the disassembly of the injection barrel. In this study, we proposed an optimization method to compensate for the wear damage of the NRVs. The V/P switchover point in each molding cycle was recalculated and output to stabilize the part quality. As a result, the wear damage of the NRV on the current machine was able to be predicted and the part quality could be initially optimized in the condition that the NRV had a degree of wear. The experimental results reveal that our proposed compensation algorithm can monitor the type of wear of NRV online, and at the same time, it can compensate the axial wear of NRV and finally improve the consistency of product weight, which established a fundamental for further research in the future.

Conductive polymer composites (CPCs) have demonstrated significant potential in the aerospace, electronics, and communications industries. In this study, polypropylene (PP)/multiwalled carbon nanotubes (MWCNTs) binary composites and in situ fiber reinforced multicomposites made from PP/MWCNTs were fabricated by microcellular injection molding. In addition to crystallization behavior,