C-SHELL
Our bio-based and compostable additive, C-Shell, reduces the use of oil-based plastic, reduces cost and improves processability.
Upcycled Waste
C-Shell is largely made from recycled oyster or eggshell. Our patent-pending process refines the shell into an additive easily integrated into various plastics and synthetic rubber production.
Bio-based and cost-effective
We provide customised solutions for our clients, delivering considerable cost reductions and improved processability. Additionally, for products utilising conventional or compostable plastic technology, we ensure a sufficient bio-based content to qualify for inclusion in the USDA Bio Preferred Program.
Reduced cost and better processability for bioplastics
Bioplastics, including PLA, have significant environmental advantages, but their cost is higher than traditional plastics and they can be challenging to process. Our C-Shell additive retains the bio-based properties of the final product while lowering material costs and enhancing processability, contributing to time and efficiency improvements during production.
Reduced cost, better processability and bio-based content for compostable plastics
Compostable plastics like PBAT offer sustainable disposal but are costly and not biobased. Our C-Shell additive is fully compostable, lowers costs, and adds significant bio-based content. Adding 26% C-Shell typically qualifies products for the USDA Bio-Preferred program.
Reduced cost, better processability and bio-based content for traditional plastics
Traditional oil-based plastic is widespread but environmentally damaging. Our C-Shell additive replaces up to 40% of oil-based plastic with a bio-based alternative, reducing environmental impact without increasing costs—and may even save money for producers. It also enhances processability. Unlike most calcium carbonate that is limestone-based and contributes to carbon emissions through quarrying, our calcium carbonate comes from upcycled oyster and eggshell waste and actually sequesters atmospheric carbon.
It works with all plastics
C-Shell is compatible with all plastic types, including bio-based and compostable options like PLA and PBAT, as well as flexible films (polyethylene), rigid containers (polystyrene, polypropylene), synthetic rubber, and more.
It also works with ink and paint
C-Shell also provides bio-based content for paint and ink products.
It’s fully recyclable
C-Shell can be added to plastic products without affecting recyclability.
What is it made from?
The exact ingredients of C-Shell are proprietary and can be adapted to our customer’s specific needs. However, our process centres on upcycling waste. We use a bio-based, compostable additive to lower costs and streamline production, most of which is made from repurposed hazardous bio-waste like eggshells and oyster shells. Unprocessed eggshells carry toxic membranes (a Category-3 hazardous waste) and dumped oyster shells damage sea floors. At Planet, we transform these waste materials into products that help cut oil-based plastic use.
Is it scalable?
Using upcycled waste as our base material positions us to scale our business effectively. Our additive is compatible with all plastics and synthetic rubbers, allowing broad market inclusion. Since plastic products are everywhere, our growth is limited only by available feedstock—which remains plentiful thanks to ongoing oyster and egg production.
Finding a valuable use for eggshell and oyster shell bio-waste
Bio-Cycle
Our Bio-Cycle additive enables plastic to biodegrade safely at the end of its life, even after multiple recycling.
It breaks plastic down for microorganisms to safely consume without leaving toxins or microplastics—only biomass, water, and CO2 remain. Bio-Cycle functions in marine, terrestrial, and landfill environments.
The formula can be tailored to a product's lifespan (usually 12-24 months), with stabilizers maintaining plastic integrity throughout use.
Our Bio-Cycle formulation can be adjusted to cater to the planned service life of a particular product - this is typically between 12 and 24 months. During such period, powerful stabilizers prevent our additive from breaking down the plastic’s mechanical properties.
At the pre-determined time, once degradation has been initiated via a free-radical process, the time it takes for the plastic material to fully bio-assimilate is dependent on several factors:
- Climate
- UV radiation
- Quantity of micro-organisms in the local environment
(Tested to EN 16472)
(Compliance with ISO 15985, ASTM 5511, ASTM 7474, ASTM 5526)
Biochar
Biochar is a form of charcoal produced from biomass. We take poultry litter and expose it to extreme heat in a zero-oxygen environment (pyrolysis) to create a nutrient-rich biochar and clean fuels.
For every 3 tons of poultry manure processed, we yield 1 ton of biochar.
Producing biochar from the waste biomass allows us to capture the carbon and prevent it from re-entering the atmosphere. Renewable energy from pyrolysis can reduce dependency on fossil fuel use and cut emissions.
