7. BioFabricating Materials¶
1.Introduction¶
What are Biomaterials?¶
Biomaterials are substances that can be processed into useful forms while remaining environmentally sustainable. They are typically made from renewable raw materials such as plants, algae, or animal by-products and can be engineered to exhibit different properties like flexibility, strength, or transparency. Depending on the recipe and process, biomaterials can mimic the qualities of plastic, resin, rubber, or even leather.
Significance of Biomaterials¶
Biomaterials hold immense significance in today’s world as we seek sustainable solutions to combat environmental challenges. The growing concern about pollution and waste management has sparked interest in materials that reduce reliance on petroleum-based products. Biomaterials are not only biodegradable but often compostable, meaning they can break down into natural components without leaving toxic residues.
For instance, the packaging industry is exploring biomaterials as alternatives to single-use plastics, while designers are integrating them into innovative products like furniture, fashion, and even electronics. Their adaptability and environmental benefits make biomaterials a key element in fostering a circular economy—a system where resources are reused and regenerated rather than discarded.
Why Are Biomaterials Important for Designers?¶
For designers, biomaterials open up new opportunities for creativity and experimentation. They allow us to rethink traditional materials and design processes, creating products that are both functional and sustainable. Incorporating biomaterials into projects can reduce environmental impact, offer unique textures and aesthetics, and encourage the use of local or waste resources.
In this project, biomaterials played a central role in exploring sustainable design. Starting with group experiments to understand the basics of biomaterial properties and applications, I later worked on an individual project to create a packaging insert using a biomaterial derived from cardboard waste. Through these hands-on experiences, I learned how to design and innovate with these materials, unlocking their potential for future projects.
2. Group Work: Experimenting with Biomaterials¶
Overview of Group Work¶
The group experiments were designed to explore the properties and potential applications of biomaterials made using gelatin and agar agar. Our goal was to understand the behavior of these materials under different conditions and assess their suitability for various use cases, such as flexibility, durability, and transparency. These experiments also served as a foundation for applying biomaterials in our individual projects.
We chose gelatin and agar agar as our base ingredients due to their natural origins and widespread use in biomaterial recipes. Both are known for their ability to form gels, making them versatile for creating bioplastics, bioresins, and flexible films.
Biomaterial Recipes¶
Agar Agar Flexible Biofoil¶
- Recipe:
The biofoil was created using agar agar powder, glycerine (as a plasticizer), and water.
| Polymer | Plasticizer | Solvent | Additive |
|---|---|---|---|
| 5g (agar agar) | 15g (glycerine) | 250g (water) | 1g (food coloring) |
- Procedure:
- Combine agar agar, glycerine, and water in a pot.
- Heat the mixture on low to medium heat while stirring continuously to dissolve the agar agar completely.
- Once the solution is homogenous, pour it into a flat mold or tray and let it set at room temperature or in a dehydrator.
- Results:
The resulting material was flexible and had a smooth texture. It exhibited moderate strength and could be bent without cracking. However, it was sensitive to moisture and became brittle when over-dried. - Comments:
This biofoil showed potential for applications requiring flexibility, such as food wraps, but further testing is needed to improve its resistance to humidity.
Agar Agar Bioplastic¶
- Recipe:
This bioplastic used agar agar powder, glycerine, and water in a slightly different ratio to experiment with flexibility.
| Material name | Polymer | Plasticizer | Solvent | Additive |
|---|---|---|---|---|
| bio-Plastic | Agar 4 g | Glycerine 12 g | Water 200 g | Food coloring 1 g |
- Procedure:
- Mix the ingredients thoroughly in a pot.
- Heat the mixture while stirring until it thickens.
- Pour the thickened solution into a mold and allow it to dry.
- Results:
The material was sturdy and less flexible than the biofoil. It dried into a semi-transparent sheet with good durability but showed shrinkage during the drying process. - Comments:
This bioplastic could work well for rigid applications like packaging or containers, but the shrinkage needs to be controlled.
Gelatine BioResin¶
- Recipe:
Gelatine, water, and a plasticizer such as glycerine were used to create a transparent and strong resin.
| Material name | Polymer | Plasticizer | Solvent | Additive |
|---|---|---|---|---|
| Bioresin | 48g (gelatine) | 8g (glycerine) | 240g (water) |
- Procedure:
- Dissolve gelatin in warm water and add glycerine.
- Heat the mixture gently while stirring until fully dissolved.
- Pour the solution into a mold or layer it thinly on a surface to dry.
- Results:
The bioresin dried to a glossy, transparent finish with a firm texture. It was strong but prone to brittleness if the proportions were not balanced. - Comments:
This material could be ideal for decorative applications or as a protective coating, provided its brittleness is minimized.
Gelatine Bioplastic¶
- Recipe:
A mixture of gelatin, water, and glycerine was used.
| Material name | Polymer | Plasticizer | Solvent | Additive |
|---|---|---|---|---|
| bio-Plastic | Gelatine 48 g | Glycerine 12 g | Water 240 g | Coffee ground 3 g |
- Procedure:
- Dissolve gelatin in warm water and mix with glycerine.
- Heat the mixture while stirring to ensure homogeneity.
- Pour the solution into molds or spread it thinly to form sheets.
- Results:
This material was flexible and easy to work with, though slightly less durable than the agar agar bioplastic. - Comments:
Its flexibility makes it suitable for applications like flexible packaging or membranes.
Gelatine BioSilicone¶
- Recipe:
Gelatine, glycerine, and water were mixed in specific proportions to mimic the properties of silicone.
| Material name | Polymer | Plasticizer | Solvent | Additive |
|---|---|---|---|---|
| bio-silicone | Gelatine 48 g | Glycerine 24 g | Water 240 g |
- Procedure:
- Mix all ingredients and heat gently.
- Pour the mixture into molds and allow it to set and dry.
- We used the petri dishes and dried samples from the Biochromes week to pour the biosilicone.
- Results:
The resulting material was elastic and smooth, resembling silicone in texture. However, it lacked the durability of commercial silicone. - Comments:
This material could be a promising alternative for soft components or prototypes but needs refinement for strength and longevity.
General Observations¶
- Comparisons Between Materials:
- Agar agar-based materials were more moisture-sensitive than gelatin-based ones.
- Gelatine bioplastics offered better flexibility, while agar agar bioplastics were sturdier.
- Key Takeaways:
- Adjusting the ratio of plasticizers significantly impacts flexibility and strength.
- Drying conditions (time, temperature, and humidity) play a crucial role in the final material quality.
- Challenges and Exploration:
- Both gelatin and agar agar showed shrinkage during drying.
- Finding the right balance between flexibility and durability remains a key area for further development.
3. Individual Assignment: Packaging Insert from Cardboard-Based Biomaterial¶
Project Overview¶
For my individual assignment, I focused on designing and creating a sustainable packaging insert for the modular educational kit I developed during the E-Textiles week. The objective was to develop an eco-friendly insert that would securely organize the kit’s modules while aligning with sustainable design principles. I selected cardboard waste as the base material for the biomaterial, as it is abundant, biodegradable, and fits well within the ethos of reducing and reusing waste.
Designing the Mold¶
Software and Process
The mold design was created in Fusion 360, starting with the module footprints. The process involved careful planning to ensure practicality, ease of production, and user-friendliness.
Design Steps:
-
Footprint Layout:
- I measured the dimensions of each module to ensure the packaging insert could securely hold them. This was critical for creating a snug fit to prevent the components from moving during storage or transport.
- Arranged the module footprints into a compact, logical layout that grouped related components together. This not only made the insert more intuitive for users but also optimized the mold size.
-
Sketching and Extrusion:
- Created the sketches for the insert’s layout, ensuring the shapes were simple yet functional.
- Extruded the sketches with a slight draft angle (a taper) to make it easier to release the biomaterial insert from the mold after drying. This small detail is critical in mold design to prevent damage during demolding.
-
Creating the Shell:
- Used the shell tool in Fusion 360 to hollow out the design with a uniform wall thickness. This reduced material usage while maintaining structural integrity.
- A uniform wall thickness ensured even drying of the biomaterial, reducing the risk of warping or cracking.
-
Fillets for Corners:
- Rounded all corners and edges with fillets to avoid sharp edges that might tear the biomaterial or make the insert difficult to handle. Fillets also improved the aesthetic appeal of the design.
-
Mold Split and Drainage Holes:
- Designed the mold in two parts for ease of use and to facilitate demolding.
- Incorporated drainage holes in strategic locations to allow excess liquid to escape during the molding process, improving drying time and reducing the risk of imperfections.
Challenges and Solutions:
- Achieving symmetry for the mold halves required precise alignment during the design phase. I double-checked measurements and used reference lines to ensure accuracy.
- To prevent air pockets during molding, I strategically placed drainage holes and designed the mold to minimize complex shapes.
3D Printing the Mold¶
Preparation:
- Imported the mold design into Cura and experimented with slicer settings to ensure good print quality.
- Initial prints using a brim failed due to poor bed adhesion, especially given the size and complexity of the mold.
Printing Process:
- Switched to using a raft, which significantly improved adhesion and stability during printing. The raft provided a solid base for the mold to adhere to, preventing warping and improving overall print success.
- Used PLA filament for its ease of use and suitability for creating molds at low temperatures.
- Printing the mold took several hours due to the inclusion of details like fillets, drainage holes, and draft angles.
Observations:
- The printed mold captured all the design details accurately.
- Adjusting slicer settings, such as increasing the bed temperature and using a raft, was key to achieving a successful print.
Creating the Biomaterial Mixture¶
This biomaterial recipe was developed to create a rigid yet slightly flexible packaging insert with a wall thickness of 3mm. The mixture uses recycled cardboard and paper pulp, starch as the primary binder, gelatin for added flexibility and durability, and glycerin as a plasticizer to reduce brittleness.
Ingredients¶
| Material | Quantity | Notes |
|---|---|---|
| Cardboard + Paper Waste | ~100g (dry weight) | Soaked and blended into pulp |
| Water | ~350–400ml total | Divided for soaking, blending, and gels |
| Starch (e.g. cornstarch or potato starch) | 8g | Pre-cooked into a gel |
| Gelatin Powder | 5g | Bloomed and melted |
| Glycerin | 3g | Added as plasticizer |
Tools Needed¶
- Blender
- Mixing bowl
- Heat-resistant saucepan or pot
- Spatula or mixing spoon
- Digital scale
- Measuring cup
- Mold (3D printed for packaging insert)
- Clamps or weights (to press the mold)
Preparation Procedure¶
1. Prepare the Cardboard Pulp¶
- Tear ~100g of cardboard and paper into small pieces.
- Soak in warm water for at least 2–4 hours (or overnight for better results).
- Blend the soaked mixture until it forms a smooth pulp. Add water as needed for smooth blending.
2. Cook the Starch Gel¶
- In a small bowl, mix 8g starch with 50ml cold water to form a slurry.
- Boil 150ml water in a saucepan, then slowly stir in the starch slurry while mixing continuously.
- Keep stirring on low heat until the mixture thickens into a smooth translucent gel.
- Remove from heat and set aside.
3. Prepare the Gelatin Solution¶
- In a separate bowl, add 5g gelatin to 50ml cold water and let it sit for 5–10 minutes to bloom.
- Gently heat the bloomed gelatin (do not boil), stirring until it dissolves completely into a liquid solution.
4. Combine All Components¶
- In a large bowl, mix the cardboard pulp with the starch gel while both are still warm.
- Add the gelatin solution and mix well until uniform.
- Finally, add 3g glycerin and stir thoroughly.
5. Mold and Press¶
- Scoop the mixture into your mold, spreading it evenly across all surfaces and corners.
- Press it firmly using weights or clamps to remove excess moisture and compact the material.
- Keep pressed for at least 4–6 hours.
- used extra mixture to fill various objects and molds
6. Drying¶
- Carefully remove the insert from the mold to avoid deformation.
- Dry it in a well-ventilated space or in an oven at 50–60°C for 8–12 hours.
- Optionally, flip or rotate the piece halfway through drying for even results.
- Let the final piece cure at room temperature for another 24 hours for maximum strength.
Notes¶
- Adjust glycerin if the material is too soft or too brittle.
- Always inspect for mold or spoilage if storing the mixture for reuse.
- This recipe produces a rigid yet slightly flexible insert that holds its shape well and is fully biodegradable.
Final Results¶
Outcome:
- The finished packaging insert successfully held the modular components in place, fulfilling its intended purpose.
- The biomaterial had a smooth surface texture, and the fillets ensured the edges were soft and user-friendly.
Strengths and Limitations:
- Strengths: The insert was lightweight, eco-friendly, and functional.
- Limitations: Minor shrinkage and the need for further refinements in the material mixture to enhance durability.
Areas for Improvement:
- Experiment with faster or more controlled drying methods to reduce shrinkage.
- Adjust the biomaterial recipe to improve strength and resistance to humidity.
4. Experimenting with Kombucha¶
Introduction to Kombucha Biomaterial¶
Kombucha biomaterial, often referred to as SCOBY leather, is a sustainable, bio-based material grown from the fermentation of sweet tea using a symbiotic culture of bacteria and yeast (SCOBY). As the culture feeds on the sugar, it forms a thick cellulose layer on the surface of the liquid. Once harvested and dried, this layer becomes a flexible, leather-like material that can be used in design, fashion, packaging, and more.
Experimenting with kombucha in the context of biomaterials is especially exciting because it involves a regenerative process. Unlike other bioplastics that rely on extracted or processed materials, kombucha leather is grown—making it an accessible, low-waste, and potentially circular material. It aligns perfectly with the themes of sustainability and local material sourcing that are central to biomaterial research.
Process Overview¶
To begin the experiment, I sourced a SCOBY from a previous fermentation and prepared a fresh batch of sweetened black tea. The steps were as follows:
Ingredients: Kombucha Biomaterial¶
| Ingredient | Amount |
|---|---|
| Water | 1 L |
| Tea | 1.5–3 g |
| Sugar | 100 g |
| Vinegar | 0–100 ml |
| SCOBY Mother | About 8 cm in diameter |
| SCOBY Solution | A splash |
-
Brewing the Tea:
- I boiled water and steeped several tea bags, then added a generous amount of sugar (which acts as the food source for the SCOBY).
- Once the tea cooled to room temperature, I poured it into a clean container and added the SCOBY.
-
Fermentation:
- The container was covered with a breathable cloth and left at room temperature in a dark place.
- Over the next several days, I observed a thin layer forming at the surface, gradually thickening with time.
- No additives or flavorings were introduced during this stage, as I was focusing on growing a pure cellulose sheet.
Observations and Results¶
-
Growth Rate & Conditions:
- The kombucha layer took about 10–14 days to form a substantial thickness suitable for harvesting.
- Room temperature and low disturbance were important factors; cooler environments slowed down the growth significantly.
-
Texture & Appearance:
- When wet, the material was gelatinous and slippery.
- Once dried, it transformed into a translucent, amber-colored film with a texture similar to dried fruit leather or thin parchment.
- The final sheet was flexible and had slight elasticity, although it could become brittle if over-dried.
-
Potential Applications:
- The kombucha leather could be used for experimental fashion, accessories, or biodegradable packaging.
- It is also compostable, making it a strong candidate for temporary or disposable products that still require visual and tactile quality.
Next Steps¶
I plan to continue experimenting with kombucha biomaterial by:
- Dyeing the SCOBY with natural pigments during fermentation or post-processing to explore color integration.
- Embedding elements such as fabric or thread into the SCOBY as it grows, to enhance its strength or appearance.
- Testing coatings (like beeswax or natural oils) to make the dried kombucha waterproof or more durable.
- Prototyping products such as pouches, tags, or soft lamp shades using the dried kombucha leather.
This material shows great promise, and I’m looking forward to developing more functional and aesthetic applications using kombucha-based biomaterials.
5. Conclusion¶
Summary of Learnings¶
This week provided a hands-on introduction to the fascinating world of biomaterials. Through the group experiments, I learned how natural ingredients like gelatin and agar agar can be combined with plasticizers, solvents, and additives to create a range of biodegradable materials, from flexible films to rigid plastics and resins. Each recipe reacted differently depending on the proportions and drying conditions, and it became clear that small tweaks can drastically affect texture, strength, and elasticity.
The individual assignment allowed me to take this understanding further by applying biomaterials to a real-world use case. Designing and producing a custom packaging insert using cardboard waste gave me deeper insight into how biomaterials can be molded and shaped, and how design for molding requires careful planning, like including draft angles, fillets, and drainage. I also saw the potential and limitations of bio-based composites when drying, as they can shrink, warp, or crack if not treated correctly.
Future Prospects¶
There are several areas I would like to explore further. One is refining the biomaterial mixture for better strength and flexibility, especially for structural uses like packaging. I also want to experiment with surface finishes and coatings to improve water resistance and texture. Another avenue of exploration is using colorants, natural dyes, and patterning during the molding or drying process to enhance aesthetics.
In terms of projects, I’m excited by the idea of integrating biomaterials into product packaging, small containers, or wearable elements. There’s also a lot of potential in combining digital fabrication tools like 3D printing or laser cutting with bio-based materials for hybrid designs.
Personal Reflection¶
This week challenged me to think like both a designer and a material researcher. It was a delicate balance between following recipes and adapting them based on how the material behaved in real-time. Some parts didn’t work on the first try, especially the mold printing and early drying attempts but through trial and error, I found better methods and adjusted accordingly.
More than anything, this week emphasized the importance of designing responsibly. Biomaterials offer an exciting, low-impact alternative to plastics, but they also come with their own design rules and limitations. Understanding how to work within those limits, and creatively push them, is what made this experience so rewarding.