Bioplastic + Wax

Bioplastic + wax : experimentations testing the water resistance of different recipes (Fabricademy, FabTextiles, Fab Lab Barcelona, 2017)

Project : Test the water resistance of the gelatin-based and agar agar-based bioplastics with wax and no wax.

Process :
(1) Cook the bioplastics samples
(2) Analyze the dry samples
(3) Observe the states of the samples in the water

Material :
- gelatin
- agar agar
- glycerin
- water
- spoons, pots, jars...
- plastic or acrylic sheet (for molding the bioplastic)
- hotplates

(1) Cook the bioplastics samples

For making bioplastics you need a biopolymer for the strength, a plasticiser for the flexibility, a solvent for the solubility and additives (optional) for the esthetic.
In this recipe I choose gelatin and agar agar as biopolymer, glycerol as plasticiser, water as solvent and wax + mineral pigment as additives.
The gelatin made with pig skin contains collagen that is good for the regeneration of your skin and the fortification of your bones. The human body needs collagen to fight against osteoporosis, osteoarthritis, cholesterol, aging of the skin...
The Agar agar made from algeas can provide very small amounts of essential vitamins and minerals including calcium, iron, zinc, potassium and magnesium. The agar contains a gel-like substance that can stimulate the intestines and thereby decrease constipation.
The glycerol can be obtained from animal or vegetable fats. Glycerol has surfactant properties which allows the constant maintenance of the level of hydration of the body. Glycerol helps to restore immune defenses and just like gelatin it strengthens the elasticity of the skin and its regeneration.

- Gelatin recipe : 250 ml water, 50g gelatin, 20g glycerol (78% water, 16% gelatin, 6% glycerin) + 1 small canddle of wax

- Agar agar recipe : 200 ml water, 12g agar agar, 15g glycerol (88% water, 5% agar agar, 7% glycerin) + 1 small canddle of wax

(2) Analyze the dry samples

After one week of drying, the bioplastics samples are ready to be removed from the acrylic sheet. and then recut properly. The gelatin-based bioplastic’s samples are smooth, dry and flexible. The sample with the wax is more granular than the one without. The agar agar-based bioplastic’s samples have lumps because my first recipe was missed and I melt the first batch again. The texture of the agar samples is more gelatinous and oily than the gelatin ones. The agar agar + wax is more rough than the one without.

(3) Observe the states of the samples in the water

The sample of gelatin-based bioplastic + wax (120x90 mm) last one month and a half in the water before becoming liquid again. During the experimentation I analyzed the size, the thickness, the texture and the color of the bioplastic sample, as well as the quality and the color of the water. I noticed that the first day, the texture of the sample changed from dry & hard to flexible & gelatinous ; the size and the thickness became bigger and the quality & color of the sample and water remained unchanged. After one week the size has increased by 10 mm and the thickness by 3 mm. The texture is still flexible & gelatinous, a bit more spongy than the end of the first day. The color of the sample staid the same but the water is not clear & transparent anymore but translucent & light yellowish. At 10 days, the thickness of the bioplastic reduced, the sample start to become flimsy and break easily. The color of the water is more and more green yellow and opaque. After 45 days, the sample disappeared in the water leaving a non-appetizing color, dirty green in the water. Now the question is : Is this water good for you ? Still need to analyse the water I guess.

In conlucion I can say that the gelatin-based bioplastic is easily recyclable when it’s dry because it’s possible to melt it again and re-use it. But is it a good idea to recycle in the water ? this question remains to be analyzed !