About Silicone

Silicone rubber is a relatively modern material that is at once liquid and solid, soft and firm. Made from silica - sand - as its core ingredient. As a rubber, it is resilient and rebounds, it is inert, impervious to moisture, heat, chemicals and uv.

In the art world it is used behind the scenes for mould-making and casting. Its unique properties of setting, taking a detailed impression, grabbing and yet being flexible and non-stick, have made it ideal. In the construction trade, in various grades, it is available as a material to seal and join a wide variety of building materials ranging from low-end DIY offerings for bathrooms to high-end formulas used in modern architectural feats such as The Shard in London. Beyond this, silicone is being used across other industries including healthcare, electronics, food preparation and renewable energy.

 

Silicone and the environment

Silicone as a material is often cited as a superior replacement for plastics as it has many environmental benefits including longer lifespan and non toxicity. Its main ingredient silica is an abundant element found around the globe. Less well known is its vital use in energy saving LED lighting, rechargeable lithium batteries and the encapsulation of solar cells.

With some newer exceptions, most primary stage silicone production to date uses hydrocarbons (fossil fuels). This is where most of any carbon emissions are generated. However, recent industry studies in Europe and the US have shown that the uses of silicone in the many industries and products around the world, far offset the emissions generated and in fact are greatly helping to facilitate the global transition to net zero*. In addition, one of the original major players** has in the last few years invested in decarbonising the whole of their production process, in the main by swapping to renewable energy for the primary stage of production and now offers carbon neutral silicones and project specific carbon neutrality certification for the construction industry.

Other environmental considerations for using silicone day to day, includes the use of plastic tube cartridges to distribute and 'caulk' with silicone in the building trade. Previously used cartridges are difficult to recycle without cleaning any uncured residue and so the industry has responded with the supply option of aluminium foil 'sausages' that can be used with long-life re-useable cartridges.

A final consideration is the disposal of unwanted or excess cured silicone. Whilst silicone is non toxic and will not break down into micro plastics, a sustainable method of recycling still needs to be developed and introduced.

 

Silicone in the studio

For my own silicone use, I mainly work with non-toxic, low odour, neutral cure varieties. Any cartridges if used, are cleaned to remove uncured silicone and taken to the plastics area of the local recycling centre. As of summer 2024, I am transitioning to foil packaged options and experimenting with certified carbon neutral silicone to test its properties. I am also currently investigating switching to a two part silicone which will enable me to custom mix and colour my own blends whilst also using re-usable cartridges. I have tended to keep all spare cured silicone and will be experimenting to see if it can be re-used 'granulated' as a filler in any suitable new mixes.

 

* American Chemistry Council - sustainability infographic:
https://www.americanchemistry.com/content/download/15675/file/Silicones-Carbon-Neutral-Economy-Infographic.pdf
Silicones Europe - supporting EU decarbonisation goals
https://www.silicones.eu/new-study-highlights-silicones-role-in-supporting-the-eu-decarbonisation-goals/

** Dow - carbon neutral silicones:
https://www.dow.com/en-us/market/mkt-building-construction/carbon-neutral-silicones.html