Bioplastics are gaining attention as sustainable alternatives to petrochemical-based plastics because they're derived from renewable, bio-based feedstocks. They can be used to reduce dependency on fossil fuels and minimise the environmental footprint. But can they keep this up in the long term? IDTechEx’s latest market research report looks into the topic.
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Biodegradable bioplastics
Bioplastics come in many forms, some of which are designed as direct replacements for conventional plastics, such as polypropylene (PP), polyethene (PE) and polyethene terephthalate (PET). These can be used directly in existing manufacturing processes without much adjustment, making them attractive to industries.
Some others, like polylactic acid (PLA) and polyhydroxyalkanoates (PHAs), are not as easily interchangeable with traditional plastics. They often require modifications or blending with other polymers to improve their properties. For instance, PLA has lower heat resistance compared to petrochemical-based plastics, limiting its use in high-temperature applications. PHAs' different mechanical properties restrict their use in industries that are accustomed to the strength and flexibility of conventional plastics. In most cases, bioplastics like PLA and PHAs are combined with copolymers to improve their mechanical performance, durability and versatility.
However, biodegradability is the key element that has gained significant attention, as it makes easy disposal possible.
Biodegradability is in demand
Biodegradable bioplastics are becoming increasingly popular, especially for single-use applications like packaging. They can be broken down into organic components like water, carbon dioxide and biomass, lowering the environmental impact. This demand has been driven by a range of new legislation. For example, China has exempted biodegradable bioplastics from their ban on single-use plastic, suggesting that end-of-life issues of these materials are not the same as other plastics.
To biodegrade well, these bioplastics require specific environmental conditions. If they end up in a landfill in an anaerobic environment, they will not degrade at all, as they're typically composted in industrial composting environments.
Bio-composites aim to overcome bioplastics limitations
One of the ways the industry is addressing the limitations of bioplastics is by developing bioplastic bio-composites. These combine bioplastics with bio-based fillers like natural fibres derived from wood pulp, wood flour and cotton. They are versatile, and their properties can be controlled by adjusting the proportion of filler material and biopolymers.
One of the properties that can be enhanced is their biodegradability. This is affected by the density of bio-based filler, which can speed up the breakdown of thicker and more bulky plastic applications like cutlery.
Overall, there's still a significant gap between the promise and delivery of biodegradable bioplastics. However, innovations such as bio-based composites may produce better materials to overcome these challenges.