Where does plastic waste come from? Straws and packaging bags for online ordering, tapes, and buffers in packaging boxes, and solid plastic particles in shower gels are produced in large quantities every moment. The global spread of the new crown epidemic has also spawned a sudden increase in the demand for plastic. Disposable masks, protective clothing, gloves, and the packaging of best-selling sterilization products are everywhere.
The vast majority of fossil-based plastics cannot be degraded, meaning that they may survive in nature for hundreds or even thousands of years. Since the 1980s, scientists have begun to study whether plastics can degrade and disappear through the action of microorganisms in an environment where microorganisms are active. Polylactic acid (PLA) products derived from crops such as corn are currently the most successful bio-based degradable plastics. Because it is a fully bio-based material, PLA is fully recyclable and biodegradable. It can be recovered mechanically or chemically, or in some cases, used as fertilizer through composting.
Xu Zhonghua said that there are several development directions for biodegradable bags: In addition to PLA that can completely decompose to produce carbon dioxide and water under certain conditions, there are also destructive biodegradable plastics that promote degradation through additives, as well as traditional The photodegradable plastic is added with a light-sensitive photoinitiator and other additives to the polymer chain of the plastic.
With the rise of the global plastic reduction movement, the emergence of "biodegradable plastics" on the market has been mistaken by many as "saviors", and people seem to be at ease when discarding such plastics because they imagine that these plastics will eventually Degradation in the environment will not cause harm. But it is worth noting that degradable plastics also need to be recycled, properly disposed in a specific way, and should not be discarded at will.
One of the root causes of the plastic dilemma is that during the entire life cycle of a plastic product, people's requirements for materials are changing. "During the use process, the strength, temperature resistance, and moisture resistance of plastics must meet certain conditions. Even degradable plastics must be decomposed under the combined action of specific temperature, humidity and microorganisms after being discarded. It will'disappear' on its own in a natural environment, otherwise, it cannot be used at normal temperature."
Bio-based degradable plastics are not everything. Xu Zhonghua said that at the beginning of the establishment of Total's Belgium PLA plant, it also encountered many difficulties in the promotion of products. Even now, the entire degradable plastics industry still faces a series of common challenges. For example, the cost is higher than ordinary plastics, and the use range of bio-based materials has been narrowed.
But the bigger restriction is that they cannot grab resources with food. "Whether bio-based plastics or lubricating oils are used, the biggest challenge is where the raw materials come from. First, they cannot compete with traditional grain crops for land resources. Under this basic premise, we can provide a certain raw material scale and cost as close as possible. Thailand is a very good choice for low-quality and long-term guaranteed raw material supply." Total Thailand PLA plant currently launches polylactic acid materials for different industries, which are used in food packaging, automotive interiors, etc. In general, PLA materials are more suitable for areas with higher food safety requirements, such as tea bags and capsule coffee.
Based on the above reasons, the biodegradable T-shirt Trash Bag supplier believes that there is still a development process for bio-based degradable plastics from large-scale applications. If all bio-based degradable plastics are used in the world today, it will have a great impact on food supply.
At the current stage, it is more suitable for specific fields related to food and medical treatment. Perhaps in the future, we can develop carbon dioxide-based plastics that will eventually decompose into gas. But before further technological breakthroughs, there is still a long way to go before completely relying on degradable plastics.