GUIDE

Before Biomaterials Manufacturing

01

Identify Components

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Raw Materials

• 1. Biopolymer : they are those that bind the other ingredients, that is to say, we have the gelatin, the agar agar, the sodium alginate and the pine resin.

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• 2. Plasticizer : its quantity determines that the material is more flexible or more rigid, generally we use glycerin or wax.

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• 3. Additive : all the food residues that we have collected and treated to make them
• collected, and treated so that they are completely dry and crushed. Organic matter, dyes and fibers.

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• 4. Solvent : dissolve the biopolymer so that we can integrate it with the other materials. We use water or alcohol depending on the biopolymer. The diluent is an active component during manufacture but then disappears by evaporation.

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Main

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Prepare raw materials

02

We will have prepared the food waste already dried and shredded. For this, it is important to prepare days in advance the collection in our community, school or neighborhood.

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Once the additives have been collected, keep them in separate and closed containers for a maximum of 2 days, and dry them as soon as possible in an oven at 70°C with the fan on, for 2 to 4 hours - or until they are dry - periodically opening the door to let the humidity out.

Grinding &

sieving

Once dried, they can be stored in separate jars for later crushing. Once crushed, they can be separated according to their "granulometry" with sieves of different mesh density.

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Thus, we can have orange peel in granule format, or in powder format. Both can be excellent additives for different recipes, depending on what you want to achieve.

Additives

Preparing the Molds

03

Before starting, check with a level that the work surface is level, and place the molds on the flattest area to prevent liquids from "escaping from the mold" while the mixture is being poured.

Level

For recipes based on gelatin that results in a sticky surface, we will use the textile (goretex) on the smooth side. This can be replaced by other plastics, such as polyethylene. This way the mixture adheres to the surface, since gelatines tend to deform during their drying process if they contain little glycerin.

Gelatin molds

If we want the surface of the resulting material to have textures, this can be easily achieved by looking for a textured textile or plastic, such as bubble wrap in packaging, or some silicone surfaces for the kitchen.

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For gelatin we can also use other types of molds, with glass, mirror or plastic surfaces; such as acrylic containers or tupperware (then we will have to wash them very well or leave their use exclusively for pouring materials).

Gelatin molds

For recipes based on Agar Agar and Sodium Alginate, which greatly reduce their size during the drying process, we will use the textile (goretex) on the rougher side. In this way, the mixture adheres to the surface and loses the water decreasing its thickness, instead of decreasing its surface area (which is what happens if we pour this type of mixtures on very smooth surfaces such as plastic, glass or mirror). For this it is also important that the edge frame is made of wood, since the adherence on the edge is key, even better if we slightly overlap it with the mixture. As alternative materials to goretex fabric, - totally waterproof - we can use other types of fabrics with textures - based on cotton and polyester for example, to prevent the liquid from escaping at the time of casting, but being semi-permeable, the sample will release moisture from both its upper and lower surfaces.

Agar agar &

Alginate molds

Advance

For recipes based on Pine Resin (or rosin) we will use solid wood molds lined with baking paper. The baking paper prevents the resin from sticking directly to the wood and allows us to unmold the piece with the immediacy that we have seen in the Bootcamp.

Resin molds

Advance

Fungus

04

To avoid blooming and fungal growth in our materials, we will add to the gelatin and Agar Agar based mixtures a small amount of vinegar, or drops of essential oils. In general, vinegar does not have a major impact on the result of the samples, apart from the odor it emits during cooking and drying. This odor disappears with time. The essential oil droplets, on the other hand, give a pleasant aroma to the samples, however, sometimes these oils can change the color of the samples or alter their consistency at the time of preparation in the pot, experiment with it.

Prevent fungus

growth

05

How do you know when a mixture is ready to pour?

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Gelatine

Agar Agar

The Agar Agar is a very fast recipe, you have to take the time, and if you miss the time, the mixture will start to gel in the pan. So you have to pour it very fast.

To be avoided in the agar agar

Resin

Advance

Safety Considerations

06

1. Use the same safety considerations as when handling liquids and hot pans, use gloves if necessary to avoid getting burned.

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1. Clean the work surface with alcohol before starting to work and at the end.

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1. Avoid using utensils and tools intended for food, or to use them later in the manufacture of materials.

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