Knowledge Agora



Similar Articles

Title Number of Times Recycled and Its Effect on the Recyclability, Fluidity and Tensile Properties of Polypropylene Injection Molded Parts
ID_Doc 15267
Authors Huang, PW; Peng, HS
Title Number of Times Recycled and Its Effect on the Recyclability, Fluidity and Tensile Properties of Polypropylene Injection Molded Parts
Year 2021
Published Sustainability, 13, 19
Abstract The ease with which modern plastics can be injection molded makes them very suitable for the production of many different products and, today, plastics are often used as substitutes for metal. Polypropylene (PP) is one of the most widely used thermoplastics globally since it is very useful, cost-effective and flexible for molding. However, the amount of harm to the environment caused by plastic waste has become phenomenal and the recycling of plastics has become a serious aspect of environmental protection. PP, as the most commonly used plastic material, was selected for use in this study. It has a melt flow index of 15 g/min and its recyclability, fluidity, and physical properties, as well as manufacturing conditions, were explored in relation to the number of times the material could be recycled (TR). A cavity pressure sensor was used to measure the viscosity index of the recycled plastic after multiple cycles of plasticizing and injection, part molding, scrap-recycling, and crushing. A paperclip-shaped test specimen was used to determine PP fluidity and crystallinity of specimens with different TRs. Tensile tests were used to detect differences in the tensile strength between specimens made from Raw-PP and recycled PP. The results showed that PP that had been recycled several times had a higher melt flow index, material fluidity, melting peak area, crystallinity, crystallization rate, and crystallization temperature. Repeated injection and recycling of the material had reduced the length of the molecular chains and broadened the molecular weight distribution. This improved the fluidity and increased crystallinity. The increase in fluidity made cavity filling easier, reducing the cavity pressure as well as the viscosity index. The results of this study showed that the recycling of the PP could improve the physical properties of the products to a degree and also went some way to further the benefits of a circular economy. The recycling of injection-molded PP material can be added to renewable energy technologies and used in environmental impact assessment.
PDF

Similar Articles

ID Score Article
6614 Galve, JE; Elduque, D; Pina, C; Javierre, C Life Cycle Assessment of a Plastic Part Injected with Recycled Polypropylene: A Comparison with Alternative Virgin Materials(2022)International Journal Of Precision Engineering And Manufacturing-Green Technology, 9, 3
4807 Sanetuntikul, J; Ketpang, K; Naknaen, P; Narupai, B; Petchwattana, N A circular economy use of waste metalized plastic film as a reinforcing filler in recycled polypropylene packaging for injection molding applications(2023)
21899 Eriksen, MK; Christiansen, JD; Daugaard, AE; Astrup, TF Closing the loop for PET, PE and PP waste from households: Influence of material properties and product design for plastic recycling(2019)
25941 Tratzi, P; Giuliani, C; Torre, M; Tomassetti, L; Petrucci, R; Iannoni, A; Torre, L; Genova, S; Paolini, V; Petracchini, F; Di Carlo, G Effect of Hard Plastic Waste on the Quality of Recycled Polypropylene Blends(2021)Recycling, 6, 3
12657 Gall, M; Steinbichler, G; Lang, RW Learnings about design from recycling by using post-consumer polypropylene as a core layer in a co-injection molded sandwich structure product(2021)
13555 O'Rourke, K; Wurzer, C; Murray, J; Doyle, A; Doyle, K; Griffin, C; Christensen, B; Brádaigh, CMO; Ray, D Diverted from Landfill: Reuse of Single-Use Plastic Packaging Waste(2022)Polymers, 14, 24
13997 Gu, F; Hall, P; Miles, NJ Performance evaluation for composites based on recycled polypropylene using principal component analysis and cluster analysis(2016)
27366 Juan, R; Paredes, B; García-Muñoz, RA; Domínguez, C Quantification of PP contamination in recycled PE by TREF analysis for improved the quality and circularity of plastics(2021)
13561 Tramis, O; Garnier, C; Yus, C; Irusta, S; Chabert, F Enhancement of the fatigue life of recycled PP by incorporation of recycled opaque PET collected from household milk bottle wastes(2021)
8362 Costa, AA; Martinho, PG; Barreiros, FM Comparison between the Mechanical Recycling Behaviour of Amorphous and Semicrystalline Polymers: A Case Study(2023)Recycling, 8.0, 1
Scroll