Why Are Disposable Biodegradable Plates Better for the Environment?

Of the 460 million tons of plastic waste generated worldwide each year, disposable plastic products account for more than 50% (United Nations Environment Programme data). Among them, food packaging containers have become a major disaster area for plastic pollution due to their huge consumer base. Against this background, disposable biodegradable plates have gradually entered the public eye.
1. Environmental friendliness at the molecular level
Traditional petroleum-based plastics (such as PP/PS) are composed of long-chain hydrocarbons, and the C-C bond energy in their molecular structure is as high as 348 kJ/mol, which takes more than 500 years to be naturally photolyzed or oxidatively decomposed. Biodegradable materials that meet the EN 13432 standard (such as PLA/PBAT) have ester bonds or amide bonds in the main chain, and their bond energy is only 150-200 kJ/mol, which can be quickly hydrolyzed by lipases and proteases secreted by microorganisms under industrial composting conditions.
In a composting environment at 58°C, the degradation rate of PLA dinner plates can reach more than 95% within 90 days, and the metabolites are only CO₂, H₂O and humus. In contrast, traditional plastics will continue to release phthalate plasticizers during the degradation process, which have been proven to have endocrine disrupting effects (WHO, 2021).
2. Substantial reduction of carbon footprint
Life cycle assessment (LCA) data show that the full-cycle carbon emissions of corn-based PLA dinner plates are 1.2 kg CO₂eq/kg, which is only 31.6% of polypropylene dinner plates (3.8 kg CO₂eq/kg). This difference mainly comes from:
Raw material stage: Plants fix carbon through photosynthesis, and 1.8 tons of CO₂ can be fixed for every ton of PLA produced;
Processing stage: The molding temperature of bioplastics is 40-60°C lower than that of traditional plastics, with significant energy-saving effects;
End treatment: The compostable characteristics avoid persistent pollutants such as dioxins (toxic equivalent factor TEF=1) produced by incineration.
It is worth noting that the EU's latest Green Deal has included bio-based materials in the carbon trading system, and companies can obtain 85 euros in carbon credits for each ton of biodegradable plastics they use.
3. Systematic avoidance of microplastic pollution
A model prediction in the journal Nature Sustainability shows that about 17% of traditional plastic tableware will enter the marine ecosystem through runoff after use. These materials are broken into microplastic particles <5mm under ultraviolet and mechanical action, with a specific surface area of ​​up to 3000 m²/g, which are very easy to adsorb carcinogens such as polycyclic aromatic hydrocarbons (PAHs) and produce a biomagnification effect through the food chain.
The biodegradable plates certified by DIN CERTCO will form a porous honeycomb structure after the material is broken, which is conducive to the colonization and decomposition of microorganisms. The simulation test of the Rhine Laboratory in Germany confirmed that in the marine environment, the complete mineralization time of PBAT-based plates is only 3-5 years, and no secondary microplastic pollution will be generated.
4. Key carriers of the closed loop of the circular economy
In the field of coordinated treatment of organic waste, degradable plates show unique value. When entering the anaerobic digestion system together with kitchen waste:
Its carbon-nitrogen ratio (C/N=25:1) perfectly matches the metabolic needs of methanogens, increasing biogas production by 22%;
The short-chain fatty acids such as butyric acid produced by degradation can serve as electron donors for denitrifying bacteria, improving sewage treatment efficiency;
The final residue meets the EU 2019/1009 standard for organic fertilizers, achieving a transformation from "cradle to grave" to "cradle to cradle".