7. Biofabricating Materials

Inspirational Images

I like the structural aspect to the first two images and the textural aspect in the third.

Research photo credits 1. bio-plastic made by Weronika Bielawska 2. Mixed media artist Margaret Byrd 3. Penny Di Roma

My Favorite Outcomes

My Questions About Bioplastics

Answers I have found show that the ratio of materials used to make bioplastics will have a big impact on strength, flexibility, stiffness, and brittleness of the resulting materials.

1) Can you sew through them?

2) How sturdy are they? What kind of force will they withstand? A few answers:

1. Adding too much glycerin can make the material weaker and remain sticky.

2. More agar increases strength and stiffness

3. The optimal ratio for strength across various concentrations appears to be around 60% agar to glycerin by weight. Glycerin adds flexibility and elongation but generally decreasesthe overall tensile strength. A high glycerin concentration results in a softer, more jelly-like material, while a low concentration produces a more rigid, possibly brittle material.

4. Compared to conventional plastics: 1) lower heat resistance 2) low to no water resitance

3) What in my life that I use is a bioplastic and I didn't know it?

4) Is bioplastic any kind of plastic NOT made of petroleum?

5) How thin can I make it and still have it be of use?

6) What is PLA and what is it being used for?

7) How do we know certifiable bioplastics and which are we currently using?

Below are two images from Patricia Vizcaya's Fabricademy site that I find useful and interesting.

Inspiration and Research

Thanks to Fabricademy 2024 | Shefali Desai for her beautiful website that has helped me with my experimentation. https://class.textile-academy.org/2025/shefali-desai/assignments/week07/

## Materials in Tennessee region relevant for biofabrication Various forms of lignocellulosic biomass (wood species, bark, grasses), native Tennessee hardwood, limestone, and agricultural waste.

While specific biofabrication products are manufactured in the region, the foundational natural materials are largely raw, organic, or mineral in origin.

Informational Video

Ingredients & Recipes

Recipe #1: Agar-Based Bio-Plastic

Ingredients: 1) 1 teaspoon agar powder 2) 3 tablespoons water 3) 1 tablespoon glycerin 4) 1 drop food coloring

Instructions:

1) In a small pan, mix the agar powder with water. 2) Heat on low while stirring constantly until the mixture thickens. 3) Add glycerin & continue stirring until the texture is smooth and silky. 4) Add a drop of color...I melted some ice cream topping into this piece, perhaps not a great idea. It is what makes the bioplastic kind of sparkly.

Results from the Recipe Above

## Happy Accident

Recipe #2: Gelatin and Glycerin Bio-Plastic

Ingredients:

1) 3 tablespoons gelatin 2) 1 tablespoon glycerin 3) 1/2 cup water 4) 1 drop food coloring

Instructions:

Prepare the Mixture:

1) Heatwater in a pan until it’s warm but not boiling. 2) Gradually dissolve the gelatin into the water, stirring to avoid clumps. 3) Add glycerin and continue stirring until the mixture is fully combined and smooth. 4) I added a drop of blue food coloring.

I poured it all into a baking tray, with a textured silicone oven pad, a few leaves, and a plastic soda bottle holder, just to see what the bioplastic sticks to and if any of these items will create any interesting texture. I am interested in making some leaf earrings, so will use this piece to test some various approaches.

I do not particularly like my results from the above recipes because they were a bit flimsy. I probably added too much Glyerin.

I do like the sheet below that were pieces I scraped away from the inside of my cooking pot. They are a combination of results from the two recipes above. I think this accident shows that letting the cooking melt way down is helpful. I love how thin and strong these pieces are.

Trying to Make Something Work/Functional

Recipe #3:

I want to make drop earrings from bioplastic, so have found the recipe below. After making it and letting the resulting plastics dry, this is definitely my most successful recipe and outcome overall. I am very happy with the result from this recipe!

A "bio-resin" recipe with a lower glycerine-to-gelatine ratio is recommended, as this results in a harder, less flexible material.

Durable Gelatin Bioplastic Recipe:"Good for casting solid, more rigid objects suitable for jewelry."https://www.google.com/search?q=recipe+for+gellatin+bioplastic+to+make+drop+earrings+from&rlz=1C1CHZN" Ingredients: 1) Gelatine powder: 48 grams (the polymer) (=1.693 ounces) 2) Glycerine: 8-12 grams (the plasticizer) (8 grams = .282 ounces) = 1.6920005 teaspoons 3) Water: 240 ml (the solvent) (8.12 ounces) (1.014 cups) 4) Optional: 2-4 drops of essential oil (as an antibacterial agent to prevent mold) 5) Optional: Pigments, food coloring, or natural dyes

Materials: 1) Saucepan 2) Measuring scale and measuring spoons 3) Spoon (avoid whisking to prevent bubbles) 4) Non-stick surface or mold (silicone, glass, or a plastic sheet works well) 5) Coffee filter or kitchen paper (for removing froth) 6) Hole punch or small drill (for making holes for earring hooks)

Instructions: 1) Mix and Dissolve: In a saucepan, combine the cold water and gelatine powder. Stir until the gelatine is completely dissolved and no lumps remain.

2) Heat: Warm the mixture on the stove over medium-low heat. Stir slowly and continuously, keeping the temperature below 80°C (176°F) to avoid boiling.

3) Add Plasticizer: Once the mixture is liquid and homogeneous, add the measured glycerine and essential oil (if using). Continue to stir gently. 4) Simmer: Simmer for at least 15 minutes, or up to an hour, while stirring regularly. Longer cooking times will evaporate more water, resulting in a thicker liquid and a more rigid, less-shrinking final product, which is ideal for small, solid items like earrings. The mixture should reach a honey-like consistency before casting. 5) Remove Froth: Use a spoon or coffee filter to remove any white foam/froth that forms on the surface for a clearer finish. 6) Color and Cast: If using colorants, remove the mixture from the heat and stir them in. 7) Slowly pour the mixture into your molds or onto your non-stick surface, pouring into one spot to minimize air bubbles. You can embed decorative elements like fine glitter or dried flower petals at this stage. 8) Dry and Finish: Let the material dry in a well-ventilated, dry room for 2-5 days. Thicker pieces will take longer. 9) Regularly turn the piece over to ensure even drying and prevent molding. 10) Once completely dry and solid (it will feel like a hard plastic, not gummy), gently de-mould. 11) Use a small drill or hole punch to create holes for attaching earring hooks or jump rings. 12) Tip: If you have any scraps or mistakes, you can re-melt them later to reuse the material.

Below is my result, with some food coloring dropped rather than stirred in. After a few hours of drying I can already tell this is my best batch. It is thinner than my other samples and I think I'm going to like some of the areas of color. I like the way the parchment wrinkles from the moisture of the bioplastic and creates a texture, which is why I placed these samples onto parchment paper, over a silicone mat placed in a cookie tray.

A hard bioplastic recipe for making jewelry.

I am including the recipe here for future use, although I have not yet tested it.

Ingredients: 1) 4 tablespoons water 2) 2 tablespoons cornstarch 3) 1 tablespoon white vinegar 4) 1 tablespoon glycerin 5) Optional: food coloring or other additives like glitter or dried petals

Instructions: 1) Mix the base ingredients: In a saucepan, combine the water, cornstarch, vinegar, and glycerin. Stir thoroughly until there are no lumps. 2) Add color (optional): If desired, add a few drops of food coloring or other decorative elements at this stage. 3) Heat the mixture: Place the saucepan over medium-low heat and stir continuously. The mixture will begin to thicken into a smooth, viscous gel. 4) Remove from heat: Once the consistency is similar to pudding and pourable, remove it from the heat. Be careful, as the mixture will be hot and sticky. 5) Pour into a mold: Carefully pour the mixture into your chosen mold or spread it in a thin layer on a non-stick surface. For a harder plastic, use a thinner layer. 6) Let it dry: Allow the bioplastic to air dry for at least 24 hours. It may take longer depending on the thickness and humidity. 7) Unmold and finish: Once completely dry and hard, carefully remove the bioplastic from the mold. It can then be cut, sanded, and assembled into jewelry

Kombusha Leather (Microbial Cellulose)

Growing the Pellicle 1) Brew strong, sweet tea 2) Use a ratio of roughly 1 cup of sugar and 8 tea bags (black or green tea work well) per gallon of water. Allow the tea to cool completely to room temperature before proceeding. 3) Set up the culture: In a clean, wide container (a wider surface area encourages faster pellicle growth), combine the cooled sweet tea with about 2 cups of mature, unflavored starter kombucha liquid and the existing SCOBY culture. Sterilize all the tools and containers with alcohol to prevent contamination. 4) Ferment: Cover the container with a coffee filter or a clean cloth secured with a rubber band to allow airflow while keeping out contaminants like fruit flies.

5) Place it in a warm, dark place away from direct sunlight and leave it undisturbed. 6) Grow to desired thickness: Allow the new pellicle to grow for 2-4 weeks. For a sturdy, leather-like material, aim for a thickness of 10-15 mm (about 1/2 inch) or more, as it will shrink considerably when it dries.

I have placed this pot in a dark room of my house, and will check in a few weeks to see if it's ready.