State of the art of thermal molding technologies applied to plastic recycling

A systematic review

Authors

DOI:

https://doi.org/10.56162/transdigital571

Keywords:

plastic recycling, molding technologies, , polymers, mechanical properties, mechanical recycling

Abstract

The increasing generation of plastic waste and the limited efficiency of recycling systems demand technologies capable of transforming recovered materials with stability and performance. The objective of this systematic review was to synthesize recent advances in thermal molding technologies applied to plastic recycling. The review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 guidelines. The search was carried out in the Scopus and Web of Science databases on May 27, 2025, applying filters for accessibility, language, document type, and the 2014–2024 period. After screening and the application of inclusion and exclusion criteria, 26 articles were selected for qualitative analysis. The results indicate that injection molding is the most widely used technology for processing recycled polymers, followed by compression molding and, less frequently, rotational molding, thermoforming, and cast film processes. Recycled polyolefins (polypropylene and polyethylene) predominate as raw materials, whereas polyethylene terephthalate, polystyrene, and acrylonitrile butadiene styrene show lower usage frequency. The evidence indicates that process parameters, compatibilization, reinforcement, and thermal history have a decisive influence on molding efficiency and the performance of recycled materials. In addition, advances were identified in equipment development and in the integration of pre-conditioning stages. Overall, the findings suggest that an integrated approach combining thermal control, formulation, and process design is essential to improve the stability and quality of products manufactured from recycled polymers.

Author Biography

José Aurelio Sosa Olivier, Juárez Autonomous University of Tabasco, Mexico

PhD in Science in Ecology and Management of Tropical Systems. Full-time Professor-Researcher at the Universidad Juárez Autónoma de Tabasco.

References

Bashirgonbadi, A., Saputra Lase, I., Delva, L., Van Geem, K. M., De Meester, S., & Ragaert, K. (2022). Quality evaluation and economic assessment of an improved mechanical recycling process for post-consumer flexible plastics. Waste Management, 153, 41–51. https://doi.org/10.1016/j.wasman.2022.08.018

Beghetto, V., Sole, R., Buranello, C., Al-Abkal, M., & Facchin, M. (2021). Recent Advancements in Plastic Packaging Recycling: A Mini-Review. (17), 4782. https://doi.org/10.3390/ma14174782

Belblidia, F., Gabr, M. H., Pittman, J. F. T., & Rajkumar, A. (2023). Recycling high impact polystyrene: Material properties and reprocessing in a circular economy business model. Progress in Rubber, Plastics and Recycling Technology, 39(4), 343–369. https://doi.org/10.1177/14777606231168653

Bocz, K., Ronkay, F., Decsov, K. E., Molnár, B., & Marosi, G. (2021). Application of low-grade recyclate to enhance reactive toughening of poly (ethylene terephthalate). Polymer Degradation and Stability, 185, 109505. https://doi.org/10.1016/j.polymdegradstab.2021.109505

Cestari, S., J. Martin, P., R. Hanna, P., P. Kearns, M., Mendes, L. & Millar, B. (2021). Use of virgin/recycled polyethylene blends in rotational moulding. Journal of Polymer Engineering, 41(6), 509-516. https://doi.org/10.1515/polyeng-2021-0065

Chen, S., & Hu, Y. H. (2024). Advancements and future directions in waste plastics recycling: From mechanical methods to innovative chemical processes. Chemical Engineering Journal, 493, 152727. https://doi.org/10.1016/j.cej.2024.152727

Czarnecka-Komorowska, D., Nowak-Grzebyta, J., Gawdzi?ska, K., Mysiukiewicz, O., & Tomasik, M. (2021). Polyethylene/Polyamide Blends Made of Waste with Compatibilizer: Processing, Morphology, Rheological and Thermo-Mechanical Behavior. Polymers, 13(14), 2385. https://doi.org/10.3390/polym13142385

Czepiel, M., Ba?kosz, M., & Sobczak-Kupiec, A. (2023). Advanced Injection Molding Methods: Review. Materials, 16(17), 5802. https://doi.org/10.3390/ma16175802

Daniele, R., Armoni, D., Dul, S., & Alessandro, P. (2023). From Nautical Waste to Additive Manufacturing: Sustainable Recycling of High-Density Polyethylene for 3D Printing Applications. Journal of Composites Science, 7(8), 320. https://doi.org/10.3390/jcs7080320

De Castro, B. D., De Faria, P. E., Vieira, L. M. G., Rubio, C. V. C., Maziero, R., De Matos Rodrigues, P. C., & Rubio, J. C. C. (2020). Recycled Green PE Composites Reinforced with Woven and Randomly Arranged Sisal Fibres Processed by Hot Compression Moulding. Acta Technologica Agriculturae, 23(2), 81–86. https://doi.org/10.2478/ata-2020-0013

Dziadowiec, D., Walburg, K., Matykiewicz, D., Andrzejewski, J., & Szostak, M. (2024). Development of Technologies for Processing Polypropylene Foil Waste and Their Use in the Production of Finished Products. Materials, 17(21), 5192. https://doi.org/10.3390/ma17215192

Fu, H., Xu, H., Liu, Y., Yang, Z., Kormakov, S., Wu, D., & Sun, J. (2020). Overview of Injection Molding Technology for Processing Polymers and Their Composites. ES Materials and Manufacturing, 8, 3–23. https://doi.org/10.30919/esmm5f713

Garcia, F. L., Nunes, A. O., Martins, M. G., Belli, M. C., Saavedra, Y. M. B., Silva, D. A. L., & Moris, V. A. da S. (2021). Comparative LCA of conventional manufacturing vs. additive manufacturing: the case of injection moulding for recycled polymers. International Journal of Sustainable Engineering, 14(6), 1604–1622. https://doi.org/10.1080/19397038.2021.1990435

Gupta, A., Misra, M., & Mohanty, A. K. (2021). Novel sustainable materials from waste plastics: compatibilized blend from discarded bale wrap and plastic bottles. (15), 8594–8605. https://doi.org/10.1039/D1RA00254F

Huang, P.-W., & Peng, H.-S. (2021). Number of Times Recycled and Its Effect on the Recyclability, Fluidity and Tensile Properties of Polypropylene Injection Molded Parts. Sustainability, 13(19), 11085. https://doi.org/10.3390/su131911085

Ji, H., & Jung, H. (2023). Effect of the multiple injection process on the structural and mechanical properties of PP impact copolymers focusing on the deformation of ethylene-propylene copolymer. Polymer Testing, 124, 108051. https://doi.org/10.1016/j.polymertesting.2023.108051

Kalauni, K., Vedrtnam, A., Sharma, S. P., Sharma, A., & Chaturvedi, S. (2025). A comprehensive review of recycling and reusing methods for plastic waste focusing Indian scenario. Waste Management & Research: The Journal for a Sustainable Circular Economy, 43(9), 1378–1399. https://doi.org/10.1177/0734242X241308499

Karahan, M., Özyurt, ?., Atalay, S. Ö., Turan, ?. Y., Haji, A., & Karahan, N. (2024). Comparative study of virgin and recycled polyethylene terephthalate and polypropylene intermingled thermoplastic composites. Polymer Composites, 46(4), 3820–3836. https://doi.org/10.1002/pc.29209

Li, H., Aguirre-Villegas, H. A., Allen, R. D., Bai, X., Benson, C. H., Beckham, G. T., Bradshaw, S. L., Brown, J. L., Brown, R. C., Cecon, V. S., Curley, J. B., Curtzwiler, G. W., Dong, S., Gaddameedi, S., García, J. E., Hermans, I., Kim, M. S., Ma, J., Mark, L. O., Mavrikakis, M., Olafasakin, O. O., Osswald, T. A., Papanikolaou, K. G., Radhakrishnan, H., Sanchez Castillo, M. A., Sánchez-Rivera, K. L., Tumu, K. N., Van Lehn, R. C., Vorst, K. L., Wright, M. M., Wu, J., Zavala, V. M., Zhou, P., & Huber, G. W. (2022). Expanding plastics recycling technologies: chemical aspects, technology status and challenges. Green Chemistry, 24(23), 8899–9002. https://doi.org/10.1039/D2GC02588D

Möllnitz, S., Feuchter, M., Duretek, I., Schmidt, G., Pomberger, R., & Sarc, R. (2021). Processability of Different Polymer Fractions Recovered from Mixed Wastes and Determination of Material Properties for Recycling. Polymers, 13(3), 457. https://doi.org/10.3390/polym13030457

Müller, M., Kolá?, V., & Mishra, R. K. (2024). Mechanical and Thermal Degradation-Related Performance of Recycled LDPE from Post-Consumer Waste. Polymers, 16(20), 2863. https://doi.org/10.3390/polym16202863

OECD. (2022, febrero 22). La contaminación por plásticos crece sin cesar debido a las deficiencias en la gestión de residuos y el reciclaje, según la OCDE. Página web oficial de la Organisation for Economic Co-operation and Development. https://www.oecd.org/en/about/news/press-releases/2022/02/plastic-pollution-is-growing-relentlessly-as-waste-management-and-recycling-fall-short.html

O’Rourke, K., Millar, B., Doyle, A., Doyle, K., Griffin, C., Hartmann, M., Christensen, B., Ó Brádaigh, C. M., & Ray, D. (2024). Diverted from landfill: Manufacture and characterisation of composites from waste plastic packaging and waste glass fibres. Sustainable Materials and Technologies, 39, Article e00851. https://doi.org/10.1016/j.susmat.2024.e00851

Page, M. J., McKenzie, J. E., Bossuyt, P. M., Boutron, I., Hoffmann, T. C., Mulrow, C. D., Shamseer, L., Tetzlaff, J. M., Akl, E. A., Brennan, S. E., Chou, R., Glanville, J., Grimshaw, J. M., Hróbjartsson, A., Lalu, M. M., Li, T., Loder, E. W., Mayo-Wilson, E., McDonald, S., McGuinness, L. A., Stewart, L. A., Thomas, J., Tricco, A. C., Welch, V. A., Whiting, P., Moher, D., … Alonso-Fernández, S. (2021). Declaración PRISMA 2020: una guía actualizada para la publicación de revisiones sistemáticas. Revista Española de Cardiología, 74(9), 790–799. https://doi.org/10.1016/j.recesp.2021.06.016

Pick, L., Hanna, P., & Gorman, L. (2022). Assessment of processibility and properties of raw post-consumer waste polyethylene in the rotational moulding process. Journal of Polymer Engineering, 42(4), 374–383. https://doi.org/10.1515/polyeng-2021-0212

Polychronopoulos, N. D., & Vlachopoulos, J. (2018). Polymer processing and rheology. In M. A. Jafar Mazumder, H. Sheardown, & A. Al-Ahmed (Eds.), Functional polymers (pp. 1–47). Springer International Publishing. https://doi.org/10.1007/978-3-319-92067-2_4-1

Ragaert, K., Delva, L., & Van Geem, K. (2017). Mechanical and chemical recycling of solid plastic waste. Waste Management, 69, 24–58. https://doi.org/10.1016/j.wasman.2017.07.044

Ronkay, F., Molnar, B., Gere, D., & Czigány, T. (2021). Plastic waste from marine environment: Demonstration of possible routes for recycling by different manufacturing technologies. Waste Management, 119, 101–110. https://doi.org/10.1016/j.wasman.2020.09.029

Sanetuntikul, J., Ketpang, K., Naknaen, P., Narupai, B., & Petchwattana, N. (2023). A circular economy use of waste metalized plastic film as a reinforcing filler in recycled polypropylene packaging for injection molding applications. Cleaner Engineering and Technology, 17, 100683. https://doi.org/10.1016/j.clet.2023.100683

Sinchai, A., Boonyang, K., & Simmala, T. (2024). Development of a Low-Cost Automated Injection Molding Device for Sustainable Plastic Recycling and Circular Economy Applications. Inventions, 9(6), 124. https://doi.org/10.3390/inventions9060124

Singkronart, K., Virkajärvi, J., Salminen, K., Shamsuddin, S. R., & Lee, K. Y. (2024). Immiscible Polymer Blends Made from Industrial Shredder Residue Mixed Plastic with and without Melt Blending. ACS Applied Polymer Materials, 6(11), 6252–6261. https://doi.org/10.1021/acsapm.4c00360

Stachowiak, T., Postawa, P., Chmielarz, M., & Grzesiczak, D. (2024). Analysis of Mechanical and Thermal Properties of Polymer Materials Derived from Recycled Overprinted Metallized PP Films. Materials, 17(8), 1739. https://doi.org/10.3390/ma17081739

Sultana, S., Sarker, M. K. U., Islam, Z., & Islam, M. S. (2022). Comparative Analysis of Compression Molded Products of Recycled Waste Poly(Vinyl Chloride) and Virgin Poly(Vinyl Chloride) Fill Material . Journal of Engineering and Technological Sciences, 54(4), 220412. https://doi.org/10.5614/j.eng.technol.sci.2022.54.4.12

Synyuk, O., Musia?, J., Zlotenko, B., & Kulik, T. (2020). Development of Equipment for Injection Molding of Polymer Products Filled with Recycled Polymer Waste. Polymers, 12(11), 2725. https://doi.org/10.3390/polym12112725

Takenaka, N., Tominaga, A., Sekiguchi, H., Nakano, R., Takatori, E., & Yao, S. (2017). Creation of Advanced Recycle Process to Waste Container and Packaging Plastic — Polypropylene Sorted Recycle Plastic Case —. Nihon Reoroji Gakkaishi, 45(3), 139–143. https://doi.org/10.1678/rheology.45.139

Tominaga, A., Sekiguchi, H., Nakano, R., Yao, S., & Takatori, E. (2019). Advanced recycling process for waste plastics based on physical degradation theory and its stability. Journal of Material Cycles and Waste Management, 21, 116–124. https://doi.org/10.1007/s10163-018-0777-7

UNEP. (2023, abril 25). Todo lo que necesitas saber sobre la contaminación por plásticos. Página web oficial del Programa para el Medio Ambiente. https://www.unep.org/es/noticias-y-reportajes/reportajes/todo-lo-que-necesitas-saber-sobre-la-contaminacion-por-plasticos

WWF. (2024, marzo 20). Piden a empresarios unirse al Pacto de los Plásticos de México. Página web oficial de la World Wildlife Fund. https://www.wwf.org.mx/?387330/Piden-a-empresarios-unirse-al-Pacto-de-los-Plasticos-de-Mexico

Autor de correspondencia

El autor de correspodencia se identifica con el siguiente símbolo: *

Published

06-01-2026

How to Cite

Córdova Palma, J. L., López Ramos, A., Sosa Olivier, J. A., & Laines Canepa, J. R. (2026). State of the art of thermal molding technologies applied to plastic recycling: A systematic review. Transdigital, 7(13), e571. https://doi.org/10.56162/transdigital571

Issue

Section

Research reports

Categories