MIRA 2023 - Risk & Reward

MIRA Virtual 2023

Risk & Reward

Filament Recycling and Sustainability Explored

This discussion is focused on PLA plastic

Index

1. Greenwashing

2. Compost-safe PLA

3. Filament Recycling

4. Filament Extrusion

5. Sustainable Slicing

Alyssa WhartonDigital Makerspace Coordinator Cole Morgan Digital Makerspace Technician UNC Wilmington Randall Library Digital Makerspace

6. Making More with Molds

7. Challenges

8. Our Applications

9. Discussion

10. Supplemental Articles

Greenwashing

Friendly marketing doesn't make it eco-friendly

PLA:What we KNOW

• Bioplastic is still plastic
• Made from crops like sugar cane or corn
• PLA needs industrial composting settings
• PLA can use toxic dyes to color
• A lot of web and news articles about PLA being recyclable and biodegradable have bias
• Biodegradable does not provide a timeline
• PLA cannot breakdown naturally

Compost-Safe PLA

compost friendly examples

• Polyterra
• Matterhackers
• Overture
• Colorfabb Allpha
• 3DPrintLife Algix Alga

Filament Recycling Systems

Pulverize filament (hammer, blender).

Sift to small pieces (1/4" or 1/8"). No need to add/mix with virgin material.

Feed into hopper of extruder system (fine tune for quality).

Wind filament onto a spool.

Felfil Evo & Spooler+$1522.71

Filastruder$299.99 Filawinder $169.00

Filament Extrusion Systems

Filabot Ex2 Extruder Steup$6560.70

Wellzoom B$588 Extruder Line E $3580.00

Sustainable slicing

If using Recycled Filament:

• Increase perimeters
• Light infill
• Use for drafts/prototypes
• Draft mode
• Ideal with Prusa

• Using Supports only when needed (adjust overhang threshold)
• Reducing infill (5%-15%)
• Infill type (use patterns that print faster)
• Build plate placement

Making more with molds

Bec Conrad from NCSSM is using panini presses to create recycled PLA sheets for laser cutting. Students sort filament, smash and blend scraps, and then press into sheets.

• Pressing sheets
• Injection molding
• Melting scraps using molds

Challenges

There will still be waste

Buildup

Time-consuming

Difficult to find composting companies that accept PLA

Recycled filament is inconsistent

Not fully biodegradable

Our Applications

Step 2

Step 3

Step 1

PLA scraps we can't compost are processed & pulverized. We use the filastuder extrusion system to recycle non-compostable scraps.PLA MUST be kept separate and use separate systems from other plastics.

All filament approved for composting is taken to Wilmington Compost for industrial processing. This filament is triple-checked before sending. If there are any doubts about brand or compostability, it is not sent for composting.

Use recycled filament for prototype prints and quick tests.Composted filaments will someday be used as soil for our Farmbot project. Other scraps are waste and sent to landfill.

Supplemental Articles

• Bhiogade, A., Kannan, M., & Devanathan, S. (2020). Degradation kinetics study of Poly lactic acid(PLA) based biodegradable green composites. Materials Today: Proceedings, 24, 806–814. https://doi.org/10.1016/j.matpr.2020.04.389
• Chen, C.-C., Chueh, J.-Y., Tseng, H., Huang, H.-M., & Lee, S.-Y. (2003). Preparation and characterization of biodegradable PLA polymeric blends. Biomaterials, 24(7), 1167–1173. https://doi.org/10.1016/s0142-9612(02)00466-0
• Ghorpade, V. (2001). Laboratory composting of extruded poly(lactic acid) sheets. Bioresource Technology, 76(1), 57–61. https://doi.org/10.1016/s0960-8524(00)00077-8
• Kopinke, F.-D. ., Remmler, M., Mackenzie, K., Möder, M., & Wachsen, O. (1996). Thermal decomposition of biodegradable polyesters—II. Poly(lactic acid). Polymer Degradation and Stability, 53(3), 329–342. https://doi.org/10.1016/0141-3910(96)00102-4
• Sun, Y., Lee, D., Wang, Y., Li, S., Ying, J., Liu, X., Xu, G.-Y., Gwon, J., & Wu, Q. (2020). Thermal decomposition behavior of 3D printing filaments made of wood‐filled polylactic acid/starch blend. Journal of Applied Polymer Science, 138(9), 49944–49944. https://doi.org/10.1002/app.49944
• V, C. (2019, July 23). Is PLA filament actually biodegradable? 3Dnatives. https://www.3dnatives.com/en/pla-filament-230720194/