Biomaterials are those materials that are either found in nature, can be created by organisms, or can be made in the lab from re-combinations of starter materials found in nature. The recent increased interest in biomaterial innovation is rooted not only in finding substitutes for petroleum-based materials, but in working within biological systems through both natural metabolisms and created metabolisms.
In natural metabolisms, sometimes referred to a g-i-y, or grow-it yourself, organisms make our materials, as is the case with kombucha leather or mushroom composites.
Created metabolisms use biologically derived ingredients to fabricate materials with lab equipment, such as starch-, gelatin- or agar- based bioplastics.
Like all materials in nature, some are extremely ephemeral, like a flower petal, some can last a very long time indeed, like wood. All are ultimately biodegradeable.
Scroll down for "nature's technologies" examples:
There are many recipes for bioplastics available on the internet involving readily available feedstocks and basic cooking-type instructions. We have derived a reliable recipe that forms a flexible sheet similar to vinyl in its consistency, that is easy to dye with food coloring.
Ingredients:
60 ml water
6 grams potato starch
6 grams gelatin
6 grams glycerin(3g makes a stiffer sheet)
Procedure:
1. Mix all ingredients well in 400 ml beaker, using glass stirring rod
2. Place on hotplate, set to heat level of 6 or 7 (medium setting)
3. Continue stirring with glass stirring rod until mixture begins to turn whitish and thickens slightly
4. Turn off hotplate.
5. Carefully, using the beaker tongs, pour the liquid out into the tray provided
6. Tilt tray to make sure the liquid reaches all 4 corners, lay on heatproof surface
7. Make a label with your name on it, attach to tray.
8. Wash out beaker and stirring rod using warm water.
Note: overheating or rapid stirring will cause bubbles to form that will impact your results
Mushrooms are decomposers, sending branching networks of mycelium through dead organic material that act to physically and chemically break down matter. Mycocomposites use mushrooms to break down waste organic material such as wood chips or sawdust, and turn it into a material with properties similar to styrofoam, that can be grown into virtually any shape. Ecovative is the company that leads in innovating this material, and DIY kits and instructions are available at grow.bio
At the heart of the biodesign curriculum is encouraging a deeper understanding of how nature works: how it forms and uses materials, how form follows function, how all life is integrated in nested and overlapping cycles.
Kombucha leather is made from the dried scoby (symbiotic colony of bateria and yeast) that grows in the presence of sweet tea to the length and width of the container its grown in. Glass containers are ideal for this, as they are easy to sterilize - a new, unscratched plastic container will also work.
Kombucha leather recipe
Ingredients
Premade sweet tea using the following ratio:
7 cups water, 1 cup sugar, 4 teabags)
Store bought kombucha (live, plain)
Directions:
1. Wear gloves
2. Clean gloves and container with alcohol. Allow to dry.
3. Add prepared sweet tea and premade kombucha in a 3:1 ratio.
4. Loosely seal container so that gas exchange can still occur while dust is kept out
5. Place in a clean, moderately warm spot, away from direct sunlight
6. When scoby is a minimum of 10 mm, harvest by removing from the container, rinsing, patting dry and laying on a flat unfinished piece of wood.
7. Drying times vary with temp and humidity, but should be less than 1 week
Notes:
1. Make sure sweet tea is completely cooled before adding the live scoby!
2. Creation of the scoby can be sped up by placing your container on top of a heated seedlng grow mat