Sealex: the new alternative to plastics
If you’ve ever had a Kinder Egg, you’ve probably seen its bright orange plastic covering around a yellow plastic capsule separating the two portions of the egg’s contents. When you break the Kinder egg in half, you’ll notice a plastic spoon lightly glued to one of the plastic seals containing a part of the contents from one half of the plastic eggshell and another plastic seal separating the other half. After peeling the plastic wrapper off the egg half with the plastic spoon attached, you’ll find two chocolate wafer balls held within a white, milky cream substance that makes this edible desert. Now, when you peel the plastic seal off the other half of the Kinder egg, you might find a disassembled toy that needs to be manually put together to get the figurine or object desired.
And what is that toy made of?
Plastic.
The dependence on plastics ranging from toothbrushes to bags to cars has exponentially increased in the last few decades.
We use plastic for almost everything and anything, and it’s a huge problem when you can’t get rid of it.
Like the Kinder egg, 36% of single-use plastics are used to contain or store things for food and beverage containers, whereas 85% are frequently thrown into landfills and poorly managed waste systems. Reliance on single-use plastics shows the annual production of one million plastic water bottles being purchased every minute and 5 trillion plastic bags being made and used yearly. What seems to be a harmless toy for kids is a part of only 9% of 400 million tons of total plastics recycled yearly.
Currently, the average American uses and throws away 110 pounds, or roughly 50 kilograms, of single-use plastic every year, yet, most of the waste ends up in poorer countries, only using a fraction of that amount per person. To put it into perspective, while the average Chinese citizen uses a third of the plastics used by an American, less than a twelfth of plastics used compared to the same American are used by the average Indian person.
In addition, 75 to 199 million tonnes of plastic can be found poorly discarded in the ocean, harming aquatic life disrupted by this manufactured material.
So plastics are harmful.
Now let’s break down why they’re a huge problem.
- Hard to get rid of.
The average single-use plastic, whether it’s made out of scary, big-worded materials like polyethylene terephthalate (PET), low-density polyethylene (LDPE), high-density polyethylene (HDPE), polypropylene (PP), polystyrene (PS), or expanded polystyrene (EPS), can take around 20 to 500 years to decompose through processes like photodegradation (breaking down plastics with the sun’s UV rays).
2. Expensive
The issue with many plastics used in everyday materials is that they are hard to eliminate, like polypropylene (PP), but they are also costly to recycle.
It costs around $50 to $150 to recycle a ton of plastics in a proper recycling facility.
Meanwhile, current plastic bags in the market can be made for about a cent, while paper bags take 4–5 cents to create. Hence, this makes plastic allure to manufacturers who want to produce stuff for cheap.
3. Toxic. But Not like Britney Spears.
They don’t degrade well; if they do, it takes a long time.
Plastics end up hurting poorer people in developing countries the most. Annually, 400,000 to one million people in developing countries die from the effects of poorly managed plastic waste shipped from other countries. Toxic chemicals leaked from plastic-infested landfills provoke health-related diseases and pollution accidents. And since poorer counties struggle with properly controlled waste disposal systems to get rid of the harmful chemicals from the plastics, most of the waste ends up in public spaces where people live, adding to the health hazards plastic waste brings to people.
Plastic that decomposes from processes like photodegradation release harmful pollutants into the air, soil, and water disrupting natural ecosystems and harming marine and land-dwelling life. Aquatic organisms or animals in ecosystems who end up consuming microplastics or parts of these chemicals accumulate these pollutants in the tissues or fats of their bodies. Livestock and fish that consume such materials pass them to people who might eat them. The cycle of plastics being transferred from one organism to another has recently shown visible signs of microplastics being found in the human bloodstream.
Introducing Sealex
What if we could completely eliminate the reliance on plastics with one material? A 100% natural, biodegradable material could be made at a lower cost than the current rate of manufactured plastics and even be edible.
Sealex is a new alternative material to plastics utilizing naturally-based proteins that undergo covalent bonding processes (the sharing of electrons between atoms).
Using mussels found in the ocean or clung to piers at your local beach, we are utilizing the sealants produced by these mussels to make a completely new material.
Mussels survive by planting on surfaces where they can eat nearby plankton, algae, and bacteria. They do this by using their long, flexible byssus threads, which are strands of protein, and at the end of the threads is a sticky and adhesive plaque that allows the mussels to stick onto things.
By extending the plaque, they can stick to surfaces under the sea. Since the byssus thread is made out of proteins, they become vulnerable to microbes and other bacteria that allow them to degrade.
This way, the mussel secretes a gel-like fluid called the cuticle, acting like the sealant super-protector for the byssus threads. Its cuticles are 4–6 times harder than its core, made up of threads! Once the mussels are done feeding off a specific area, they release themselves from their threads and move on to their following location.
It takes 2–3 years, with the constant pounding of natural conditions or harsh underwater weather that causes the sealant to crack. Eventually, this allows microbes to purge the rich protein underneath it through biodegradation.
How does this allow us to create a new type of sustainable “plastics?”
Breaking down the Chemistry:
The mussels utilize redox chemistry and the exchange of electrons to manufacture this sealant. Thiols are compounds in amino acid groups and substances like ethanol and some foods. DOPA is an amino acid found in thiols. When the thiol supply of the mussel depletes, these amino acids get oxidized, losing hydrogen atoms and thus making the cuticle brittle.
Taking inspiration from this process, our team created a product that utilizes the covalent bonding of two different macromolecules to produce a protein-built gel-like substance that hardens into a durable material.
Chemical Process:
First, we take two soluble macromolecules, alginate (A) and gelatin (G). Alginate is negatively charged (-), while Gelatin is positively charged (+).
Both the macromolecules, alginate, and gelatin, are dissolved into a chemical base solution substance or, in our case — water (W). When the macromolecules dissolve in water, a chemical reaction between the alginate and gelatin forms a non-soluble entity called an “alginate-gelatin hydrogel droplet.”
Once the water solution evaporates, the two macromolecules (A and G) in their hydrogel droplet form find each other to covalently bond and form our final and new non-soluble hydrogel substance.
Like when a water balloon pops after exceeding its carrying capacity, these hydrogel droplets undergo a phase separation process, where the droplets build up around each other like a balloon. Once enough alginate and gelatin combine, the droplet burst and evenly disperses the remaining hydrogel to the bottom of the water.
Once we have enough of the hydrogel droplets and they separate into their hydrogel phase, we can mold that gel into any form or shape we want. Once the mold is set, it can be dried to create a new, durable material.
When you’re done using the resulting moldable and flexible material — in other terms, Sealxlabs — it can be safely composted and discarded back into the environment. It would degrade from the forces of friction and erosion imposed on it through natural forces (ex., wind, rain, hail, or environmental conditions in bodies of water). A Sealxlabs will decompose naturally into natural polymers consisting of amino acids; voila, the material produces no harmful chemicals or toxins.
Mimicking consumer products
The flexible nature of the sealant found in Sealxlabs opens the doors for various materials to coat themselves around — ranging from solid materials (for containers) to more soft ones (for wrappers).
Why does this work better than plastics?
1) It’s cheaper than plastics. We’re using water to make it.
- The average of 1000 gallons of water in the United States costs around $1.50.
- Adding on, the chemical process runs on a supply of abundant proteins found in a local supermarket!
- Materials used to make plastic, like fossil fuels and oils, are getting harder and harder to obtain → using SealXX is a cheaper alternative for material production.
- Although clean water is scarce, the water can be reused to make the material, making the supply theoretically endless.
2) Durable and Degradable
- To visualize how strong the material is, if SealXX is put in the ocean, it will take 2–3 years to decompose from the tensions of natural forces.
3) Accessible and Easy
- The primary resources needed are water and sealant material; that’s it.
- Nature did it for millions of years; trust the chemical processes.
- They can also be easily discarded, usually into regular trash bags.
4) Sealant is also edible
- Even if it is consumed by wildlife, humans, or other organisms in an ecosystem, it’s completely edible and harmless!
By replacing the need for single-use plastics in our everyday lives, we can reduce the global footprint in both CO2 emissions and solid waste pollution.
Using biomimicry concepts and utilizing mussels’ biological components, our vision with Sealex is to build a world without plastics.
*This idea has been modified.
