'We have led an exciting breakthrough in the development and application of new materials for research and development. We have developed an internationally advanced ultra-thin, high-strength, high-tough, biodegradable mulch film new material to complete production scale, and the application of the film field is very good. Rice and other crops increase production by 20%; multi-functional shed membrane has long service life, which can help farmers save money and increase crop yield. The technology has been rated as the key achievement of the national key R&D plan basic materials in 2017. ' October 24, China Dr. Wang Hongxue, the chief expert of Petrochemical Shanghai Petrochemical Research Institute, introduced the progress made by the media to the national project of high-end agricultural film materials research and development.
In 2017, the total output of China's agricultural film reached 2.9 million tons, ranking first in the world, but the market share of low-end and mid-range products was as high as 90%. The output of high-end agricultural film was low, and the performance was still at the international level. To improve the technical level of key basic materials. In the first batch of national key research and development plans of the Ministry of Science and Technology in 2016, the new film project for agricultural film was set up. Taking this as an opportunity, Wang Hongxue, as the project leader, formed the Shanghai Institute as the lead unit, Tsinghua University, University of Science and Technology of China, Changchun Yinghua, Chinese Academy of Sciences The project team of Baishan Xifeng Plastic Industry, Shanghai Hongrui Biotechnology and Zhejiang Haizheng Biotech participated in this national agricultural film project.
'The use of non-degradable mulch film causes land pollution. Biodegradable mulch film is an effective way to solve this problem, but its industrialization and promotion progress is slow. We analyzed the reasons. First, the cost is too high, and second, the performance is insufficient. The degradation rate in the field is too fast, the service life cannot be adjusted according to the crop growth cycle, and the strength and toughness of the film are low, which is difficult to meet the requirements of mechanical filming. 'Wang Hongxue said.
To solve the problem of high cost, it is the key to manufacture low-cost biodegradable raw materials. Many microorganisms in nature can synthesize a biodegradable material - polyhydroxy fatty acid ester. This material degrades quickly, but the cost is high. Tsinghua University Professor Chen Guoqiang's team used halophilic microorganisms to develop new technologies for low-cost production of polyhydroxyalkanoates through advanced genetic engineering techniques.
'But it is very difficult to make this kind of degraded raw material into a mulch film. The processing temperature window is narrow, the thermal stability is poor, it can't be processed into a mulch film, and the mechanical strength is low, which can't reach the requirement of using the mulch film. 'Wang Hongxue said. Facing the material With its own enormous challenges, the research team has developed advanced biodegradable mulch new materials through polymer modification technology innovation. Its service life can be adjusted according to crop growth requirements, and the film strength can be improved to achieve mechanical filming, while reducing film thickness. Reducing farmers' expenditures can help solve problems that cannot be afforded because of high prices. In the future, based on a 30% replacement ratio, the use of new biodegradable mulch films can reduce the pollution of nearly 100 million mu of cultivated land and save the cost of film recycling by 10 billion yuan. Reduce carbon emissions by more than 200,000 tons. In July this year, the Ministry of Agriculture and Rural Affairs listed the full biodegradable film replacement technology as ten major leading agricultural technologies.
At the same time as the development of biodegradable mulch film, Shanghai Institute led the project team to develop high-function, long-life shed film, and made breakthroughs in the 'permanent' of many functions of shed film, and developed a variety of new high-performance shed film special materials. At the same time, it also reduces the production energy consumption and air pollution of the shed film. The new shed film not only helps the farmers to double the use period, but also saves the labor cost of changing the film in the middle, and increases the crop yield. Increase the income of farmers.
'The agricultural film project led by Shanghai Institute helped Xifeng Company improve its technology to improve quality and efficiency.' The person in charge of the project cooperation unit Xifeng Plastic Industry said that the new biodegradable film special material has good processability and can be modified without The company's multiple production lines directly scale up production; 'permanent' functional polyolefin special materials in a multi-layer co-extrusion production line, a successful test of long-lasting multi-functional composite shed film, its anti-fog, dust-proof effect The period has more than doubled compared with the original product, reaching the international advanced level.