Bio-based plastics, also known as bioplastics, are a category of plastics derived from renewable biological sources, such as plants, agricultural residues, and microorganisms. Unlike traditional plastics, which are primarily derived from fossil fuels (petroleum or natural gas), bio-based plastics offer a more sustainable alternative as they utilise biological materials that can be replenished over time. These materials can be either biodegradable or non-biodegradable, depending on their composition.
There are two main types of bio-based plastics:
- Biodegradable Bio-based Plastics:
- These plastics can break down naturally through biological processes, typically by microorganisms like bacteria or fungi. The end products of biodegradation are often water, carbon dioxide, and biomass. Examples of biodegradable bio-based plastics include polylactic acid (PLA), polyhydroxyalkanoates (PHA), and starch-based plastics.
- Biodegradable bio-based plastics are often used in applications where the disposal environment is conducive to microbial breakdown, such as compostable packaging.
- Non-Biodegradable Bio-based Plastics:
- These plastics are made from renewable resources but do not necessarily undergo complete biodegradation. Instead, they share similarities with traditional plastics in terms of durability and resistance to decomposition. However, their production involves fewer fossil fuel resources.
- Examples of non-biodegradable bio-based plastics include bio-based polyethylene (bio-PE), bio-based polyethylene terephthalate (bio-PET), and bio-based polypropylene (bio-PP).
Key characteristics and advantages of bio-based plastics include:
- Renewable Source: Bio-based plastics are derived from renewable resources, reducing dependency on finite fossil fuel reserves.
- Reduced Carbon Footprint: Production of bio-based plastics often results in lower greenhouse gas emissions compared to traditional plastics.
- Diverse Feedstocks: Bio-based plastics can be produced from various feedstocks, including sugarcane, corn, potatoes, and agricultural residues.
- Biodegradability (for Some Types): Biodegradable bio-based plastics contribute to a reduction in plastic waste and environmental impact, especially in applications where composting is feasible.
It’s important to note that while bio-based plastics offer certain environmental advantages, their overall sustainability depends on factors such as cultivation practices, land use, and end-of-life management. Additionally, not all bio-based plastics are biodegradable, and the disposal environment plays a crucial role in determining their environmental impact. The development and adoption of bio-based plastics align with broader efforts to create more sustainable materials and reduce the environmental footprint of plastic production and use.