Please read our guide to PLA bioplastic to learn all about PLA material, including how it is produced, the environmental and economic advantages of PLA, and how it fits into the circular economy.
What is PLA bioplastic?
Polylactic acid or polylactide (PLA) is a polyester derived from renewable biomass, typically from fermented plant starch, such as corn, cassava, sugarcane, or sugar beet pulp. While the feedstock currently doesn’t compete with food production, manufacturers are already investigating the use of non-agricultural feedstocks. The environmental advantages of PLA bioplastics over those plastics derived from petroleum are measurable and significant.
How PLA is produced
bioplastic PLA production process
PLA is a polyester (polymer containing the ester group) made with two possible monomers or building blocks: lactic acid and lactide. The bacterial fermentation of a carbohydrate source under controlled conditions can produce lactic acid. In the industrial-scale production of lactic acid, the carbohydrate source of choice can be corn starch, cassava roots, or sugarcane, making the process sustainable and renewable.
Research is ongoing to develop even more eco-friendly and cheaper methods of producing PLA. In addition, agricultural produce, crop residues such as stems, straws, husks, and leaves, can be processed and used as alternative carbohydrate sources. The residue that cannot be fermented can be used as a heat source to lessen the use of fossil fuel-derived hydrocarbons.
Environmental advantages of PLA
PLA is biodegradable under commercial composting conditions and will break down within twelve weeks, making it an environmental choice when it comes to plastics in contrast to traditional plastics, which could take centuries to decompose and create microplastics.
The manufacturing process for PLA is also more environmentally friendly than that of traditional plastics made from finite fossil resources. According to research, the carbon emissions associated with PLA production are 80% lower than that of conventional plastic (source).
PLA can be recycled as it can be broken down to its original monomer by thermal depolymerization or hydrolysis. The outcome is a monomer solution that can be purified and used for subsequent PLA production without losing quality.
However, the recycling infrastructure for PLA hasn’t been scaled up yet, mainly because end markets for the recycled material haven’t been developed.
While recycling PLA might be a viable solution in the future, we currently recommend composting as a preferred end-of-life option, significantly, as food service packaging is often contaminated with food scraps, making recycling impractical.
PLA Disadvantages
There are plenty of advantages to PLA, but there are some disadvantages, too. These include the environmental impact on land and water than growing crops and using fertilizer causes (even though in 2019, bioplastics represented 0.016% of total land use and 2024 projection is 0.021%; see next section (source).
Additionally, PLA plastic packaging can be more expensive than its conventional plastic counterparts due to the number of steps required in the production process. However, as PLA becomes more widely available, efficiencies of scale come into play, which means the cost can decrease.
PLA: from plants to the soil, a genuinely circular option
The production of bioplastic has little to no effect on food prices or supply. In 2018 the global production capacities for bioplastics amounted to around 2.1 million tonnes. This translates into approximately 790,000 hectares of land. The surface area required to grow sufficient feedstock for today’s bioplastic production is about 0.01% of the global agricultural area of 5 billion hectares. This ratio correlates with the size of an average cherry tomato next to the Eiffel Tower (based on market data by EUBP/IfBB/nova-Institute, 2014).
In 2023, assuming continued high growth in the bioplastics market at the current stage of technological development, a demand of around 2.6 million tonnes accounting for about 975,000 hectares of land, could be achieved. This market equates to approximately 0.016% of the global agricultural area.
