PLA is one of the mainstream degradable plastic products. Polylactic acid is a polymer polymerized from lactic acid as the main raw material. It is currently the most mature, industrialized, and most widely used biodegradable plastic in the world.
There are two methods for preparing PLA, namely lactide ring-opening polymerization method and direct polycondensation method. Among them, the lactide ring-opening polymerization method is widely used. In the lactide ring-opening polymerization method, the synthesis and purification of the intermediate lactide is the core technology and difficulty in the process. The reaction conditions are harsh, the process is complex, the technical requirements are high, and the production cost is high. It is a Chinese enterprise PLA Technical barriers to capacity expansion.
In general, Chinese companies are currently limited by technical level, product quality, production scale and other reasons, and their market share is small. As domestic companies overcome the technical difficulties of lactide, the speed of PLA production will increase significantly, and the market prospects broad.
The difficulty of PLA technology is lactide
There are two main methods for the preparation of PLA, namely lactide ring-opening polymerization method and direct polycondensation method. The ring-opening polymerization method is mainly used in industry. The technical difficulty of the industrial chain lies in the synthesis and purification of lactide.
The purification of lactide is very important in the entire ring-opening polymerization process. Only high-purity lactide can be used to synthesize PLA with high molecular weight and good physical properties. The two-step method involves the purification steps of lactide, not only the process is complicated, the cost is also high, but the purity and reaction conditions of the lactide can be controlled to realize the production of PLA with high molecular weight, controllable chemical structure and good mechanical properties.
The difficulty of PLA technology is mainly lactide. At present, China's domestic polylactic acid technology mainly relies on the cooperative research and development of enterprises and scientific research institutions. Many companies are vigorously developing lactide production technology, trying to break through the technical barriers of the PLA industry and break through the "lactic acid-lactide" -Polylactic acid" the entire industrial chain to enhance cost advantages.
