….Imagine there’s a way to turn the plastic waste that ends up in oceans and landfills into a life-saving material, say, for making cheap fire-resistant jackets for all people.
It isn’t hard to do – at least, not any more – for a team of researchers in Singapore dreaming of reducing environmental waste and sharing their breakthrough with the world….
NUS Associate Professor Hai Minh Duong, the co-leader of the research team, once used to wonder when he saw oil and plastic waste on the beach: “Can we use the rubbish on the beach to clean the oil spills?”
Fellow co-leader, Prof Nhan Phan-Thien, wanted to come up with a real product for everyone, after a lifetime of producing theories…
and for interstellar dust collection by NASA’s Stardust space probe, including in the near-distance fly-by of 81P/Wild — comet Wild 2 (top-of-diary image).
This is astoundingly strong stuff, and yet super-porous and ultralight, with
...impressive load-bearing abilities ... due to the dendritic microstructure, in which spherical particles of average size (2–5 nm) are fused together into clusters. These clusters form a three-dimensional highly porous structure of almost fractal chains, with pores just under 100 nm….
“Aerogel” refers to capabilities and properties of substances the term can apply to, rather than what substances/molecules it can be made from.
Nicknames include frozen smoke,[6] solid smoke, solid air, solid cloud, blue smoke owing to its translucent nature and the way light scatters in the material. It feels like fragile expanded polystyrene to the touch. Aerogels can be made from a variety of chemical compounds.[7]
The Singapore team sees great potential in the recycled PET plastic (in textile form, you know it as polyester!
Over 95 per cent of an aerogel’s volume is made of air, hence the material’s high internal surface area and absorbent qualities.
Based on the team’s experiments, when their aerogel is coated with certain water-repellent chemicals, it absorbs up to seven times more oil than existing commercial sorbents can – and at a faster rate.
Other every-day uses they —and we— can imagine for this aerogel “first” now that it may become economically feasible:
- Virtually FIRE-PROOF temperature and sound insulation for homes, schools and workplaces, even in vehicles such as for food transportation to prevent spoilage and prevent waste; in refrigerant appliances and maybe even as wall-fabric for emergency refugee shelters with isolated food storage compartments in them;
- Light-weight safety gear, such as for carbon dioxide absorption masks — wherever that’s a respiration hazard, such as in wildfires— and as a layer in fire-fighter uniforms and emergency cover-alls for high-rise workers who might need to escape fire or endure freezing cold;
- Routine road-way retaining-wall installation, for absorption and clean-up of spills after car accidents and truck-overturns, and for run-off filtering to improve water reclamation and protect the soil;
- In air-polluted environments, more affordable thinner filtering indoors, and outdoors a new fashion in translucent healthy face-veiling! (Especially in parts of the world with sandstorms and dust-storms more and more frequent … probably need more practical style, though…. niqab or burka-like, perhaps.)
To explain [about varying coatings on aerogels], or surface modifications, Dr Duong uses the metaphor of a video game. “That’s like an expansion pack when you buy the game,” says the 44-year-old.
“With the surface modification, you can get the wide range of applications, like if you coat the aerogels … with an amine chemical, they can absorb the toxic gases and carbon dioxide.”
The most common type of commercially available aerogel is silica aerogel, which he says sells for about S$40 per sheet (A4 size) and is used mainly in the aviation, car, gas and petroleum industries.
But his PET aerogel would cost about 50 cents to manufacture, with one recycled bottle producing one sheet.
The article says there’s about eight million tonnes of plastic waste entering the world’s oceans each year, and untold more in landfills. There is no shortage of material that could be recycled into aerogel products instead.
For decades, wealthy parts of the world have barged a lot of our trash to nations needing the “deposit” fees, where it all piles up into smoking, toxic mountains that poor people literally live on as they mine their ruined landscapes for cast-offs and recyclables — the only income by which to survive.
Maybe another application of aerogel textiles might be hazardous-waste work garb that protects the wearer whose only job possibility that is….
Maybe for a change, this massive unnatural resource might be their growth industry.
And the environment’s redemption.
Read and see more from the article at https://www.channelnewsasia.com/news/cnainsider/made-singapore-solution-world-plastic-waste-problem-aerogel-nus-11072016 and get more fantastic wikimedia images HERE.
Readers, science wonks, idealists — got more ideas for how aerogels from plastic trash could be used beneficially? Thoughts on the limitations & practicalities? Please comment! Always more worth learning.