Reprocessability of PLA through Chain Extension for Fused Filament Fabrication
Abstract
:1. Introduction
2. Materials and Methods
2.1. Materials
2.2. Methods
2.3. Extrusion of PLA-Based Monofilaments
2.4. Printability of the PLA-Based Filament
2.5. Mechanical Recycling of PLA-Based Materials
2.6. Characterization of the PLA- and PLA/PBO-Based Materials
2.6.1. Linear Mass Density and Extrusion Rate
2.6.2. Tensile Tests
2.6.3. Surface Morphology
2.6.4. Chromatic Measurements
2.6.5. Differential Scanning Calorimetry (DSC)
2.6.6. FTIR Spectroscopy
2.6.7. Melt Flow Rate (MFR)
2.6.8. Printability Assessment
2.7. Statistical Analysis
3. Results and Discussion
3.1. Extrusion of PLA-Based Filaments
3.2. Filament Tensile Performance
3.3. Morphology
3.3.1. Surface Morphology
3.3.2. Optical Measurements
3.4. Thermal Behavior
3.5. Structural Analysis
3.6. Melt Flow Rate
3.7. Printability Test
3.8. Tensile Performance of 3D-Printed Specimens
4. Conclusions
Author Contributions
Funding
Data Availability Statement
Conflicts of Interest
References
- Geyer, R.; Jambeck, J.R.; Law, K.L. Production, use, and fate of all plastics ever made. Sci. Adv. 2017, 3, 25–29. [Google Scholar] [CrossRef] [PubMed] [Green Version]
- Badia, J.D.; Ribes-Greus, A. Mechanical recycling of polylactide, upgrading trends and combination of valorization techniques. Eur. Polym. J. 2016, 84, 22–39. [Google Scholar] [CrossRef] [Green Version]
- Badia, J.D.; Gil-Castell, Ó.; Teruel-Juanes, R.; Ribes-Greus, A. Recycling of Polylactide. In Encyclopedia of Renewable and Sustainable Materials; Elsevier BV: Amsterdam, The Netherlands, 2020; pp. 282–295. [Google Scholar] [CrossRef]
- Vilaplana, F.; Karlsson, S. Quality concepts for the improved use of recycled polymeric materials: A review. Macromol. Mater. Eng. 2008, 293, 274–297. [Google Scholar] [CrossRef]
- Pillin, I.; Montrelay, N.; Bourmaud, A.; Grohens, Y. Effect of thermo-mechanical cycles on the physico-chemical properties of poly(lactic acid). Polym. Degrad. Stab. 2008, 93, 321–328. [Google Scholar] [CrossRef]
- Zenkiewicz, M.; Richert, J.; Rytlewski, P.; Moraczewski, K.; Stepczyńska, M.; Karasiewicz, T. Characterisation of multi-extruded poly(lactic acid). Polym. Test. 2009, 28, 412–418. [Google Scholar] [CrossRef]
- Sanchez, F.A.C.; Boudaoud, H.; Hoppe, S.; Camargo, M. Polymer recycling in an open-source additive manufacturing context: Mechanical issues. Addit. Manuf. 2017, 17, 87–105. [Google Scholar] [CrossRef]
- Ragaert, K.; Delva, L.; Geem, K.V. Mechanical and chemical recycling of solid plastic waste. Waste Manag. 2017, 69, 24–58. [Google Scholar] [CrossRef]
- Brüster, B.; Addiego, F.; Hassouna, F.; Ruch, D.; Raquez, J.M.; Dubois, P. Thermo-mechanical degradation of plasticized poly(lactide) after multiple reprocessing to simulate recycling: Multi-scale analysis and underlying mechanisms. Polym. Degrad. Stab. 2016, 131, 132–144. [Google Scholar] [CrossRef]
- Botta, L.; Scaffaro, R.; Sutera, F.; Mistretta, M.C. Reprocessing of PLA/graphene nanoplatelets nanocomposites. Polymers 2018, 10, 18. [Google Scholar] [CrossRef] [Green Version]
- Preparation and recycling of plasticized PLA. Macromol. Mater. Eng. 2011, 296, 141–150. [CrossRef]
- Badia, J.D.; Strömberg, E.; Karlsson, S.; Ribes-Greus, A. Material valorisation of amorphous polylactide. Influence of thermo-mechanical degradation on the morphology, segmental dynamics, thermal and mechanical performance. Polym. Degrad. Stab. 2012, 97, 670–678. [Google Scholar] [CrossRef]
- Cuadri, A.A.; Martín-Alfonso, J.E. Thermal, thermo-oxidative and thermomechanical degradation of PLA: A comparative study based on rheological, chemical and thermal properties. Polym. Degrad. Stab. 2018, 150, 37–45. [Google Scholar] [CrossRef]
- Agüero, A.; del Carmen Morcillo, M.; Quiles-Carrillo, L.; Balart, R.; Boronat, T.; Lascano, D.; Torres-Giner, S.; Fenollar, O. Study of the influence of the reprocessing cycles on the final properties of polylactide pieces obtained by injection molding. Polymers 2019, 11, 1908. [Google Scholar] [CrossRef] [PubMed] [Green Version]
- Tuna, B.; Ozkoc, G. Effects of Diisocyanate and Polymeric Epoxidized Chain Extenders on the Properties of Recycled Poly(Lactic Acid). J. Polym. Environ. 2017, 25, 983–993. [Google Scholar] [CrossRef]
- BASF. Polymeric Chain Extenders Joncry ADR-4368 Data Sheet; Technical Report; BASF Corporation: Florham Park, NJ, USA, 2008. [Google Scholar]
- Khankrua, R.; Pivsa-Art, S.; Hiroyuki, H.; Suttiruengwong, S. Effect of chain extenders on thermal and mechanical properties of poly(lactic acid) at high processing temperatures: Potential application in PLA/Polyamide 6 blend. Polym. Degrad. Stab. 2014, 108, 232–240. [Google Scholar] [CrossRef]
- Meng, X.; Shi, G.; Chen, W.; Wu, C.; Xin, Z.; Han, T.; Shi, Y. Structure effect of phosphite on the chain extension in PLA. Polym. Degrad. Stab. 2015, 120, 283–289. [Google Scholar] [CrossRef]
- Meng, X.; Shi, G.; Wu, C.; Chen, W.; Xin, Z.; Shi, Y.; Sheng, Y. Chain extension and oxidation stabilization of Triphenyl Phosphite (TPP) in PLA. Polym. Degrad. Stab. 2016, 124, 112–118. [Google Scholar] [CrossRef]
- Han, T.; Xin, Z.; Shi, Y.; Zhao, S.; Meng, X.; Xu, H.; Zhou, S. Control of thermal degradation of poly(lactic acid) using functional polysilsesquioxane microspheres as chain extenders. J. Appl. Polym. Sci. 2015, 132, 1–11. [Google Scholar] [CrossRef]
- Ramírez-Herrera, C.A.; Flores-Vela, A.I.; Torres-Huerta, A.M.; Domínguez-Crespo, M.A.; Palma-Ramírez, D. PLA degradation pathway obtained from direct polycondensation of 2-hydroxypropanoic acid using different chain extenders. J. Mater. Sci. 2018, 53, 10846–10871. [Google Scholar] [CrossRef]
- Liu, W.; Li, H.; Wang, X.; Du, Z.; Zhang, C. Effect of chain extension on the rheological property and thermal behaviour of poly(lactic acid) foams. Cell. Polym. 2013, 32, 343–368. [Google Scholar] [CrossRef]
- Alturkestany, M.T.; Panchal, V.; Thompson, M.R. Improved part strength for the fused deposition 3D printing technique by chemical modification of polylactic acid. Polym. Eng. Sci. 2019, 59, E59–E64. [Google Scholar] [CrossRef]
- Fuentes, M.A.V.; Thakur, S.; Wu, F.; Misra, M.; Gregori, S.; Mohanty, A.K. Study on the 3D printability of poly(3-hydroxybutyrate-co-3-hydroxyvalerate)/poly(lactic acid) blends with chain extender using fused filament fabrication. Sci. Rep. 2020, 10, 1–12. [Google Scholar] [CrossRef]
- Additive Manufacturing—General Principles—Terminology; Standard, International Organization for Standardization: Geneva, Swizerland, 2015.
- Brian; Redwood, B.; Schoffer, F.G. The 3D Printing Handbook; Coers & Roest: Arnhem, The Netherlands, 2013; p. 2013. [Google Scholar]
- Jordan, J. 3D Printing; The MIT Press: Cambridge, MA, USA, 2018; p. 238. [Google Scholar]
- RePET. About | RE PET 3D. Available online: https://re-pet3d.com/about/ (accessed on 1 July 2021).
- Filamentive—Recycled 3D Printing Filament UK. Available online: https://www.filamentive.com/about-filamentive-recycled-filament/ (accessed on 1 July 2021).
- Reflow. About—REFLOW. Available online: https://reflowproject.eu/about/ (accessed on 1 July 2021).
- Azevedo, J. Novo Filamento 3D Produzido a Partir de Desperdícios de Plástico dos Makers | TUCAB. Available online: https://bit.ly/2VlaUqE. (accessed on 1 July 2021).
- Gomes, T. Utilização de matéria prima secundária polimérica para aplicações em fabrico aditivo. Master’s Thesis, Universidade de Aveiro, Aveiro, Portugal, 2013. [Google Scholar]
- Sanchez, F.A.C.; Boudaoud, H.; Camargo, M.; Pearce, J.M. Plastic recycling in additive manufacturing: A systematic literature review and opportunities for the circular economy. J. Clean. Prod. 2020, 264, 121602. [Google Scholar] [CrossRef]
- Moreno, E.; Beltrán, F.R.; Arrieta, M.; Gaspar, G.; Muneta, M.L.M.; Carrasco-Gallego, R.; Yañez, S.; Hidalgo, D.; Orden, M.U.D.L.; Urreaga, J.M. Technical Evaluation of Mechanical Recycling of PLA 3D Printing Wastes. Proceedings 2020, 69, 19. [Google Scholar]
- Grigora, M.E.; Terzopoulou, Z.; Tsongas, K.; Klonos, P.; Kalafatakis, N.; Bikiaris, D.N.; Kyritsis, A.; Tzetzis, D. Influence of reactive chain extension on the properties of 3d printed poly(Lactic acid) constructs. Polymers 2021, 13, 1381. [Google Scholar] [CrossRef]
- Marec, P.E.L.; Ferry, L.; Quantin, J.C.; Benezet, J.C.; Bonfils, F.; Guilbert, S.; Bergeret, A. Influence of melt processing conditions on poly(lactic acid) degradation: Molar mass distribution and crystallization. Polym. Degrad. Stab. 2014, 110, 353–363. [Google Scholar] [CrossRef]
- GmbH, W.T. Compact—Wanner Technik GmbH. Available online: https://www.wanner-technik.de/en/granulators/compact/. (accessed on 22 June 2021).
- Tips and Tricks for Successful Tensile Testing: Stretching the Boundaries in Your Lab; Technical report; Stable Micro Systems: Surrey, UK, 2015.
- Plastics—Determination of tensile properties—Part 2: Test Conditions for Moulding and Extrusion Plastics; Standard, International Organization for Standardization: Geneva, Swizerland, 2014.
- Gonçalves, I.; Lopes, J.; Barra, A.; Hernández, D.; Nunes, C.; Kapusniak, K.; Kapusniak, J.; Evtyugin, D.V.; da Silva, J.A.L.; Ferreira, P.; et al. Tailoring the surface properties and flexibility of starch-based films using oil and waxes recovered from potato chips byproducts. Int. J. Biol. Macromol. 2020, 163, 251–259. [Google Scholar] [CrossRef]
- Plastics—Differential Scanning Calorimetry (DSC)—Part 1: General Principles (ISO 11357-1:2009); Standard, International Organization for Standardization: Brussels, Swizerland, 2009.
- Beltrán, F.R.; Lorenzo, V.; de la Orden, M.U.; Martínez-Urreaga, J. Effect of different mechanical recycling processes on the hydrolytic degradation of poly(L-lactic acid). Polym. Degrad. Stab. 2016, 133, 339–348. [Google Scholar] [CrossRef]
- Petchwattana, N.; Channuan, W.; Naknaen, P.; Narupai, B. 3D printing filaments prepared from modified poly(lactic acid)/teak wood flour composites: An investigation on the particle size effects and silane coupling agent compatibilisation. J. Phys. Sci. 2019, 30, 169–188. [Google Scholar] [CrossRef]
- Costa, A. Nanocompósitos de matriz polimérica para impressão 3D. Master’s Thesis, Universidade de Aveiro, Aveiro, Portugal, 2016. [Google Scholar]
- Zhao, X.G.; Hwang, K.J.; Lee, D.; Kim, T.; Kim, N. Enhanced mechanical properties of self-polymerized polydopamine-coated recycled PLA filament used in 3D printing. Appl. Surf. Sci. 2018, 441, 381–387. [Google Scholar] [CrossRef]
- Barletta, M.; Aversa, C.; Puopolo, M. Recycling of PLA-based bioplastics: The role of chain-extenders in twin-screw extrusion compounding and cast extrusion of sheets. J. Appl. Polym. Sci. 2020, 137, 49292. [Google Scholar] [CrossRef]
- Rasselet, D.; Caro-Bretelle, A.S.; Taguet, A.; Lopez-Cuesta, J.M. Reactive compatibilization of PLA/PA11 blends and their application in additive manufacturing. Materials 2019, 12, 485. [Google Scholar] [CrossRef] [PubMed] [Green Version]
- Gonçalves, C.M.B.; Coutinho, J.A.P.; Marrucho, I.M. 8 Optical Properties; John Wiley & Sons, Inc.: Hoboken, NJ, USA, 2010; pp. 97–112. [Google Scholar]
- Carrasco, F.; Pagès, P.; Gámez-Pérez, J.; Santana, O.O.; Maspoch, M.L. Processing of poly(lactic acid): Characterization of chemical structure, thermal stability and mechanical properties. Polym. Degrad. Stab. 2010, 95, 116–125. [Google Scholar] [CrossRef]
- Singh, N.; Singh, R.; Ahuja, I.P. Recycling of polymer waste with SiC/Al2O3 reinforcement for rapid tooling applications. Mater. Today Commun. 2018, 15, 124–127. [Google Scholar] [CrossRef]
- Ghalia, M.A.; Dahman, Y. Investigating the effect of multi-functional chain extenders on PLA/PEG copolymer properties. Int. J. Biol. Macromol. 2017, 95, 494–504. [Google Scholar] [CrossRef]
- Baimark, Y.; Srihanam, P. Influence of chain extender on thermal properties and melt flow index of stereocomplex PLA. Polym. Test. 2015, 45, 52–57. [Google Scholar] [CrossRef]
- Alexandre, A.; Sanchez, F.C.; Boudaoud, H.; Camargo, M.; Pearce, J. Mechanical Properties of Direct Waste Printing of Polylactic Acid with Universal Pellets Extruder: Comparison to Fused Filament Fabrication on Open-Source Desktop Three-Dimensional Printers. 3D Print. Addit. Manuf. 2020, 7, 237–247. [Google Scholar] [CrossRef]
Dumbbell (ISO 527-02, Type 1BA) | Regular Dodecahedron | |
---|---|---|
Toolpaths | 90°–90° | 90°–0° |
Layer height | 0.1 mm | 0.2 mm |
Bed temperature | 60 °C | 60 °C |
Extruder temperature | 190 °C | 190 °C |
Wall line count | 2 | 2 |
Top layers | 4 | 4 |
Bottom layers | 4 | 4 |
Infill density | 100% | 15% |
Travel speed | 150 mm/s | 200 mm/s |
Nozzle diameter | 0.4 mm | 0.4 mm |
Raster width | 0.5 mm | 0.48 mm |
Print speed | 40 mm/s | 80 mm/s |
G-code | Ultimaker Cura 4.9.1 | Ultimaker Cura 4.9.1 |
Average Diameter (mm) | Filament Length (m) | Extrusion Rate (m/s) | |
---|---|---|---|
vPLA | 1.764 ± 0.598 | 52.094 | 1.27 |
rPLA | 1.702 ± 0.870 (*) | - | - |
vPLA+PBO | 1.722 ± 0.221 | 62.363 | 1.39 |
rPLA+PBO | 1.740 ± 0.146 | 62.294 | 1.67 |
L | a | b | YI | ||
---|---|---|---|---|---|
vPLA | 84.682 ± 0.921 | 0.556 ± 0.037 | 1.134 ± 0.160 | - | 32.915 |
vPLA+PBO | 83.348 ± 0.957 | 0.090 ± 0.051 | 4.200 ± 0.400 | 3.376 | 37.415 |
rPLA+PBO | 85.044 ± 0.854 | 0.266 ± 0.008 | 4.432 ± 0.464 | 3.330 | 37.858 |
Tg (°C) | Tcc (°C) | Tm (°C) | X (%) | |
---|---|---|---|---|
vPLA | 64.5 | 158.4 | 174.1 | 35.77 |
vPLA+PBO | 66.2 | 159.1 | 175.0 | 24.28 |
rPLA+PBO | 64 | 155.8 | 173.7 | 32.79 |
PBO | - | - | 147.9 | - |
Formulation | Description |
---|---|
vPLA | The filament produced with the vPLA formulation was able to be printed, at the specified process parameters; moreover, the resulting components did not show evident signs of under or over extrusion, voids and layer misalignment. However, some inclusions among the deposited beads were detected and the brittle behavior of the material led to a low 3D-printing success rate; a regular dodecahedron and a set of tensile tests for accessing the mechanical performance of this formulation were able to be produced; |
rPLA | 100% recycled PLA was not able to be printed due to the extreme brittleness of the filament and, therefore, the printability analysis was not able to be conducted; |
vPLA+PBO | After chain extension, virgin PLA was able to be printed at the same processes parameters as the vPLA formulation. No evident signs of under or over extrusion, voids and layer misalignment were detected. However, due to the brittle nature of the filament only a partially printed dodecahedron was able to be produced, as well as a set of tensile specimens for accessing the mechanical performance of this formulation; |
rPLA+PBO | After chain extension, recycled PLA was able to be printed at the same process parameters as the vPLA formulation; however, evident signs of under- or over-extrusion were detected, as well as the presence of voids and layer misalignment, which were associated with the lower melt strength of this formulation. Moreover, due to embrittlement of the filament over time, it was not possible to produce the set of tensile specimens required for accessing the mechanical performance of this formulation. A regular dodecahedron for the printability test was able to be produced. |
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Correia, C.; Gomes, T.E.P.; Gonçalves, I.; Neto, V. Reprocessability of PLA through Chain Extension for Fused Filament Fabrication. J. Manuf. Mater. Process. 2022, 6, 26. https://doi.org/10.3390/jmmp6010026
Correia C, Gomes TEP, Gonçalves I, Neto V. Reprocessability of PLA through Chain Extension for Fused Filament Fabrication. Journal of Manufacturing and Materials Processing. 2022; 6(1):26. https://doi.org/10.3390/jmmp6010026
Chicago/Turabian StyleCorreia, Carlos, Tiago E. P. Gomes, Idalina Gonçalves, and Victor Neto. 2022. "Reprocessability of PLA through Chain Extension for Fused Filament Fabrication" Journal of Manufacturing and Materials Processing 6, no. 1: 26. https://doi.org/10.3390/jmmp6010026
APA StyleCorreia, C., Gomes, T. E. P., Gonçalves, I., & Neto, V. (2022). Reprocessability of PLA through Chain Extension for Fused Filament Fabrication. Journal of Manufacturing and Materials Processing, 6(1), 26. https://doi.org/10.3390/jmmp6010026