Fully Biodegradable Plastics: A New Environmental Choice, a New Trend for the Future
In today's era of increasing emphasis on environmental protection and sustainable development, plastic pollution looms like a dark cloud, shrouding the global ecosystem. In 2020, my country decisively stepped up its efforts to combat plastic pollution, issuing major documents such as the "Opinions on Further Strengthening Plastic Pollution Control" and the "Notice on Solidly Promoting Plastic Pollution Control Efforts." These documents clearly stipulate that by a specified timeframe, the use of partially biodegradable plastic bags, non-degradable disposable plastic straws, and non-degradable disposable plastic tableware will be prohibited in supermarkets, bookstores, and other locations in municipalities, provincial capitals, and cities with independent planning status. This series of powerful measures, like a clarion call for environmental protection, has quickly catapulted fully biodegradable plastics into the spotlight and become a promising alternative to traditional plastics and a promising way to alleviate plastic pollution.
The Rise of Fully Biodegradable Plastics in the Context of Plastic Pollution Control
As a new polymer material, fully biodegradable plastics offer a wide variety of types and diverse technological approaches. From a raw material perspective: it can be derived from a wide range of sources, from petrochemicals to biomass.
Different raw materials offer varying performance characteristics and application scenarios. From a degradation mechanism perspective: it encompasses a variety of processes, including biodegradation, photodegradation, and oxidative degradation. Each degradation process follows unique chemical and physical principles and operates under different environmental conditions.
Based on degradation performance: Fully biodegradable plastics are further categorized as "fully" degradable and "partially" degradable. For consumers and environmental concerns, "fully" degradable plastics are undoubtedly the preferred choice, as their degradation products are harmless to the environment and minimize negative impacts on the ecological environment.
Demystifying "Fully" Biodegradable Plastics "Fully" biodegradable plastics often raise questions.
Let's explore the underlying issues.
Not 100% Degradable: Many people assume that "fully" biodegradable plastics degrade 100% without leaving any residue, but this is not the case. According to professional testing methods such as GB/T 19277.1, 19277.2, 19276.1, 19276.2, and 28206, biodegradable plastics are considered "fully" degradable if their biodegradation rate reaches 90% or above. This is because during degradation in composting, soil, or other environments, a portion (less than 10%) of the organic carbon contained in biodegradable plastics is converted into dead organisms or mineralized inorganic salts, rather than all of it being converted into harmless end products such as carbon dioxide.
Multiple Degradation Scenarios: Does this mean it can only degrade in composting? Of course not. Composting is just one of the degradation scenarios. In fact, most biodegradable plastics will degrade in natural environments such as soil, freshwater, or seawater, as long as the temperature and humidity conditions are suitable, and they will ultimately be completely broken down by microorganisms into environmentally friendly substances. For example, materials such as PBAT, PCL, and PHA can be completely degraded in as little as six months under suitable soil and seawater conditions. PLA also has the ability to degrade in the natural environment.
