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alginatenet.md 9.09 KiB

ALGINATE NET

Tactility & sound impression

Description

a cotton/wool and alginate-based composite with open structure, molded onto a half dome shape

Physical form

Solids

Color without additives: color of the yarn used

Fabrication time

Preparation time: 1 hour (plus resting overnight)

Processing time: 5-7 days

Need attention: None, just leave it to dry on the mold

Final form achieved after: 7 days

Ingredients

  • Sodium alginate powder - 6 gr
    • the polymeer (so it becomes a solid)
  • Glycerine - 10 gr
    • the plasticizer that bonds with the alginate (makes it flexible).
  • Water - 200 ml/gr
    • to dissolve and mix the polymeer and plasticizer
    • optional: use a (diluted) natural dye instead for a colored plastic
  • Sunflower oil - 5 gr
    • filler to reduce shrinkage
  • Yarn - cotton/wool mix, 2 metres
    • to create the net
  • Calcium chloride solution 10% (10 gr to 100 gr water)
    • is the curing agent: calcium chloride attracts moisture very strongly: spraying it onto the alginate plastic starts the curing process.

Tools

  1. Scale
  2. Spoon
  3. Blender
  4. Glass jar with lid
  5. Spray bottle (150 ml contents, for the calcium chloride solution)
  6. Circular loom OR: nails and a wooden board to design the net
  7. Moulds for shaping the net, e.g. two identical bowls that fit inside one another
  8. Acrylic sheet to catch the excess alginate mixture (can be scooped up and reused before curing)

Yield before processing/drying/curing

Approx. 200 ml of alginate plastic that can be stored for two weeks and used in many different recipes

Approx. 100 ml of calcium chloride 10% solution that can be used for any alginate recipe

Method

  1. Preparation

    • Weigh your ingredients for the alginate plastic (alginate, glycerine, water) in a blender
    • Optional: use a diluted natural dye instead of water in the same amount for a colored plastic.
    • Leave the mixture overnight to allow the bubbles to come to the surface and pop.

  2. Loom preparation

    • The next day: create a net on your loom (or hammer some nails into a wooden board and use that to create a net shape). It's not important that this is a properly woven structure.
    • Push down the yarn at all the crossings, so the threads touch each other

  3. Casting

    • Place the loom on an acrylic sheet before casting to catch excess alginate mixture
    • Distribute the alginate mixture over the net, making sure it touches all the threads and crossings
    • Wipe off excess blobs, the alginate should be distributed evenly
    • Spray the net with the calcium chloride solution from all sides to start the curing process
    • After a few minutes, when it no longer feels liquid but is becoming slightly solid, take the net off the loom. The alginate will shrink a lot, if you leave it on it could get stuck.
    • Rinse the calcium chloride off the net by submerging it in tap water
    • Transfer the net onto the mold (a bowl in this case), and place the threads how you want them
    • Let it cure until totally dry

Drying/curing/growth process

  • Mold depth: N/A
  • Shrinkage thickness: 20-30 %
  • Shrinkage width/length: 20-30 %

Shrinkage and deformation control

Letting it dry up to seven days to get to the final form. When it no longer feels cool to the touch it is dry enough to take off. It can help to place a second bowl over the net to keep it in place even better.

Curing agents and release agents

Calcium chloride 10% as curing agent

Minimum wait time before releasing from mold

3 days

Post-processing

N/A

Further research needed on drying/curing/growth?

Not sure

Process

Making a net-like structure on a loom (does not have to be "proper" weaving), Loes Bogers, 2020

Preparing a 10% calcium chloride solution with hot water, Loes Bogers, 2020

The calcium chloride solution in a spray bottle, Loes Bogers, 2020

Pouring the alginate mixture onto net, Loes Bogers, 2020

You can pour a lot and scoop up the excess to use again later, Loes Bogers, 2020

Alginate evenly distributed along the yarn lines, Loes Bogers, 2020

Letting the alginate net cure and dry on top of a half-dome shape, Loes Bogers, 2020

Variations on this recipe

  • Add a natural colorant such as a vegetable dye or water-based ink (e.g. hibiscus, beetroot, madder)
  • Add more glycerine for a more flexible composite
  • You can make endless variations with the net design, and also with the mould design you cure the net on.

Cultural origins of this recipe

Alginate plastic is used a lot in molecular gastronomy, for (reverse) spherification that was patented by William J. S. Peschardt in the 1940s and popularized by the Adrian Ferra of the infamous restaurant El Bulli. Alginate plastics is also used a lot in molding and casting of dental technology industry.

Needs further research? Not sure

References this recipe draws from

The alginate recipe is a modified version of: Flexible Bio-plastic Alginate Recipe by Cecilia Raspanti (Textile Lab, Waag), Fabricademy Class "Biofabricating", 2019, link.

The technique of alginate net casting is a variation on the experiments documented by Carolina Delgado (2020) in her Fabricademy project page: https://class.textile-academy.org/2020/carolina.delgado/projects/final-project/#netting

Known concerns and contestations*

Sodium alginate

Sustainability tags

  • Renewable ingredients: yes
  • Vegan: yes
  • Made of by-products or waste: no
  • Biocompostable final product: yes
  • Reuse: no

Needs further research?: not sure

Recycling this bioplastic with PET plastics contaminates the waste stream. Compost bioplastics in a warm environment with sufficient airflow.

Material properties

Comparative qualities

The net is light and springy and feels a little like a thin hemp rope. It jumps right back into shape after squeezing it.

Technical and sensory properties

  • Strength: medium
  • Hardness: flexible
  • Transparency: translucent
  • Glossiness: matt
  • Weight: light
  • Structure: open
  • Texture: rough/medium/smooth/variable
  • Temperature: medium
  • Shape memory: high
  • Odor: none
  • Stickiness: low
  • Weather resistance: medium
  • Acoustic properties: needs further research
  • Anti-bacterial: needs further research
  • **Non-allergenic:**needs further research
  • Electrical properties: needs further research
  • Heat resistance: high, up to 150 degrees celcius
  • Water resistance: waterproof (for PH neutral and acidic water, not for alkaline water)
  • Chemical resistance: needs further research
  • Scratch resistance: high
  • Surface friction: medium
  • Color modifiers: none

About this entry

Maker(s) of this sample

  • Name: Loes Bogers
  • Affiliation: Fabricademy student at Waag Textile Lab Amsterdam
  • Location: Rotterdam, the Netherlands
  • Date: 26-02-2020 – 03-03-2020

Environmental conditions

  • Outside temp: 5-11 degrees Celcius
  • Room temp: 18 – 22 degrees Celcius
  • PH tap water: 7-8

Recipe validation

Has recipe been validated? Yes

By Cecilia Raspanti, Textile Lab, Waag Amsterdam, 9 March 2020

Estimated cost (consumables) in local currency

0,57 Euros for a yield of approx 200 ml alginate plastic (you can make a few nets with that)

Local supplier/sourcing info

Sodium Alginate powder - Unique Products Schuurman (online retailers, wholesale food stores like Sligro) Glycerine 1.23 - Orphi/Chempropack (online retailers) Calcium chloride - Circular loom - Craft shops

Copyright information

This recipe is in the public domain (CC0)

Yes

This recipe was previously published by someone else

This is a modified version of: Flexible Bio-plastic Alginate Recipe by Cecilia Raspanti (Textile Lab, Waag), Fabricademy Class "Biofabricating", 2019, link.

##References

Images of final product

Alginate net, Loes Bogers, 2020

Alginate net, Loes Bogers, 2020