Mechanical and chemical combined recycling process for CFRP scraps

Mechanical and chemical combined recycling process for CFRP scraps


download PDF

Abstract. Composite materials are increasingly employed in many industrial sectors. Among others, carbon fibers are primarily used as reinforcing agents in high-performance composites with synthetic resin matrices such as epoxies, polyimides, vinyl esters, phenolics, and certain thermoplastics. However, when carbon fibers are coupled with thermosetting matrices, the resulting composites are not easily recyclable. When these products reach their end-of-life (EoL), there are several difficulties in their recycling and in the reuse of the carbon fiber reinforcement. Several recycling process methods exist, but one of the most promising and investigated in recent years is the mechanical one, which, unlike other approaches, does not require the use of high temperatures to decompose the polymeric matrix. However, the presence of residual matrix on the surface of the fibers negatively affects their potential reuse for the production of new composites. In comparison to well-known mechanical recycling methods such as shredding, crushing, and hammer milling processes, this work presents a combined recycling process comprising mechanical recycling by milling and a soft chemical treatment at temperatures significantly lower than those reached during conventional thermal recycling processes. Recycled fibers were then used to produce new composite laminates using an epoxy resin as the matrix. The effects of the chemical treatment on the adhesion between recycled fibers and the new resin were evaluated through pull-out and bending tests.

CFRPs, Recycling, Adhesion, Mechanical Properties

Published online 4/24/2024, 8 pages
Copyright © 2024 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA

Citation: BOCCARUSSO Luca, DE FAZIO Dario, DURANTE Massimo, FORMISANO Antonio, LANGELLA Antonio, Mechanical and chemical combined recycling process for CFRP scraps, Materials Research Proceedings, Vol. 41, pp 568-575, 2024


The article was published as article 63 of the book Material Forming

Content from this work may be used under the terms of the Creative Commons Attribution 3.0 license. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.

[1] F. Pinto, L. Boccarusso, D. De Fazio, S. Cuomo, M. Durante, M. Meo, Carbon/hemp bio-hybrid composites: Effects of the stacking sequence on flexural, damping and impact properties, Compos. Struct. 242 (2020) 112148.
[2] P. Boisse, R. Akkerman, P. Carlone, L. Kärger, S.V. Lomov, J.A. Sherwood, Advances in composite forming through 25 years of ESAFORM, Int. J Mater. Form. (2022) 15-39.
[3] A. Viscusi, M. Durante, A. Astarita, L. Boccarusso, L. Carrino, A.S. Perna, Experimental Evaluation of Metallic Coating on Polymer by Cold Spray, Proc Manufact. 47 (2020) 761-765.
[4] I. Papa, P. Russo, A. Astarita, A. Viscusi, A.S. Perna, L. Carrino, V. Lopresto, Impact behaviour of a novel composite structure made of a polymer reinforced composite with a 3D printed metallic coating, Comp. Struct. 245 (2020) 112346.
[5] A. Formisano, L. Carrino, D. De Fazio, M. Durante, A. Viscusi, Enhanced Aluminium Foam Based Cylindrical Sandwiches: Bending Behaviour and Numerical Modeling, Int. Rev. Model. Simul. 11 (2018).
[6] Y. Yang, R. Boom, B. Irion, D.J. Van Heerden, P. Kuiper, H. de Wit, Recycling of composite materials, Chem. Eng. Process. Process Intensif. 51 (2012) 53-68.
[7] F. Meng F, E.A. Olivetti, Y. Zhao, J.C. Chang, SJ. Pickering, J. McKechnie, Comparing Life Cycle Energy and Global Warming Potential of Carbon Fiber Composite Recycling Technologies and Waste Management Options. ACS Sustain. Chem. Eng. 6 (2018) 9854–65.
[8] D. De Fazio, L. Boccarusso, A. Formisano, A. Viscusi, M. Durante, A Review on the Recycling Technologies of Fibre-Reinforced Plastic (FRP) Materials Used in Industrial Fields, J. Mar. Sci. Eng. 11 (2023) 851.
[9] E. MacArthur, Towards the circular economy, economic and business rationale for an accelerated transition, Ellen MacArthur Foundation, Cowes, UK, 2013.
[10] S. Gharde, B. Kandasubramanian, Mechanothermal and chemical recycling methodologies for the Fibre Reinforced Plastic (FRP), Environmental Technology & Innovation, 14 (2019) 100311.
[11] D. De Fazio, L. Boccarusso, A. Formisano, A. Langella, F. Memola Capece Minutolo and M. Durante, Mechanical recycling of CFRPs: manufacturing and characterization of recycled laminates, Italian Manufacturing Association Conference: XVI AITeM, Materials Research Forum LLC, 35 (2023).
[12] S.J. Pickering, Recycling technologies for thermoset composite materials-current status, Composites Part A: Applied Science and Manufacturing, 37 (2006) 1206-1215.
[13] L. Mazzocchetti, T. Benelli, E. D’Angelo, C. Leonardi, G. Zattini, L. Giorgini, Validation of carbon fibers recycling by pyrogasification: The influence of oxidation conditions to obtain clean fibers and promote fiber/matrix adhesion in epoxy composites, Compos. Sci. Technol. 112 (2018) 504-514.
[14] M. Durante, L. Boccarusso, D. De Fazio, A. Formisano, A. Langella, Investigation on the Mechanical Recycling of Carbon Fiber-Reinforced Polymers by Peripheral Down-Milling, Polymers 15 (2023) 854.