Source: Deeptech, “2022 China Bio-based Degradable Materials Technology and Industry Research Report”
PHA has the highest carbon neutrality score among different biodegradable materials, which is of great significance in the promotion of the “two-carbon” policy and high-quality development policy. PHA is the only material that can be rapidly degraded in the ocean and soil, and its degradation products are naturally occurring energy molecules of human beings. From an environmental point of view, PHA has environmentally friendly properties. By reducing costs through technical means, farmers can afford agricultural mulch films made of biomaterials. The ingredients can be taken from natural wastes, and actions such as not competing with others for food, etc., all reflect the care for the society.
In general, PHA has five advantages and six excellent characteristics, and is widely used in chemical, packaging, medical, agriculture, daily use, military and other fields. Thanks to its good biocompatibility, PHA is widely used in high value-added medical fields and can be used as biological implant materials for medical and therapeutic applications.
1. The research and development of PHA has gone through four development stages, and its material properties mainly depend on the monomer composition
PHA was first synthesized by Maurice Lemoigne in 1926 and has been in development for nearly a century. At present, there are more than 150 types of PHA, and the material properties of different types of PHA mainly depend on their monomer composition.
2. Synthetic biology technology has become the mainstream method of PHA production, and the two aspects jointly restrict the process of product commercialization
The general synthesis method of PHA The process flow includes raw material synthesis process, chemical process, physical process and so on. However, the preparation of traditional PHA is not only expensive, but also has shortcomings such as high energy consumption, easy contamination, complicated process, and difficult product extraction.
The development of PHA products by synthetic biology methods needs to go through three stages: transforming good strains, scaling up the process through small-scale testing, and building factories for stable production. Synthesizing a polymer material through biotechnology is like programming in cells, designing genetic codes that did not exist, and writing genetic programs to “create things”.
For PHA, three elements need to be considered for synthesis: chassis cells, carbon sources (raw materials), and metabolic pathways. Simply understand, through gene editing and other means, the chassis cells can grow faster, and can efficiently “eat” the carbon source, so that the PHA in the cells “change from thin to fat”, and improve the efficiency of carbon source conversion into PHA.
3. Synthetic biology technology has become the mainstream method of PHA production, and the two aspects jointly restrict the process of product commercialization
For the process of biological methods from laboratory scientific research results to product commercialization, the focus is on solving the problem of realizing large-scale production processes. Both the front-end strain transformation efficiency and the back-end process amplification effect play a decisive role.
• Transformation of strains: The efficiency is mainly reflected in the three indicators of conversion rate, production rate and yield of the production product. As the first step in the manufacture of synthetic organisms, it is necessary to select a strain with excellent traits according to the characteristics of the target product, also known as chassis cells, which are the host used for the production of the product. Using the method of synthetic biology, the specific target genes of the organism genome are modified and modified to achieve the purpose of modifying the metabolic pathways of microorganisms. At this stage of the synthetic biology research and development process, the cost of gene sequencing, gene editing and DNA synthesis is already very low. In the face of complex biological design, the key lies in who can screen out a reasonable gene editing solution with higher throughput and in the shortest time possible, so as to increase the rate of product development and reduce the cost of research and development.
• Back-end process amplification: mainly reflected in three aspects: high efficiency, low cost, separation and purification. As the “last rod” of the industrialization of biosynthetic manufacturing, the cost of product separation and purification accounts for more than 60% of the total cost, and the cost of separation of high value-added products can even reach 90%. Different from traditional chemical separation, biological manufacturing method has higher requirements on separation and purification technology. The biological product separation process needs to ensure the biological activity of the product, often requiring low temperature, suitable pH and pressure tolerance. Commonly used green separation and purification technologies include membrane separation technology, simulated moving bed chromatography technology and supercritical extraction technology.
4. Major breakthroughs have been made in key links such as strain cultivation, fermentation process, raw material selection, and production process
At present, PHA industry-related enterprises have made major breakthroughs in bacterial culture, fermentation process, production process and other links. Azurite Microorganisms use a highly integrated fermenter to increase the throughput of the fermentation process, accumulate process data, and shorten the research and development cycle. The fermentation process limits the speed at which strains can achieve high-throughput automation in the design, construction, and testing processes. The key lies in the degree of throughput and dataization. Ayanite microorganisms use the most advanced sensors in the field of physics and chemistry to design and develop automated and highly integrated fermenters. It is expected that the complete development cycle of a single product will be shortened by 70% on the existing basis. Microfabricated the genes of halophilic bacteria and successfully developed “next-generation industrial biotechnology”. In order to overcome the shortcomings of industrial biotechnology due to high energy consumption, water consumption, huge equipment investment and complex process, Microstructure Factory used synthetic biology technology to re-edit the genes of halophilic bacteria and successfully developed “next-generation industrial biotechnology” , including its theory, model, molecular operation, laboratory culture technology, pilot technology and industrial production technology, as well as the application of some products. The halophilic bacteria are re-engineered so that they can efficiently generate various chemicals and materials using seawater as a medium in a non-sterilization and continuous process. Taking the production of environmentally friendly plastics and biomaterials polyhydroxyalkanoate PHA as an example, the halophilic bacteria have achieved ultra-high PHA accumulation (92%) and controllable deformation through the transformation of synthetic biology.
Beijing Bennong Environmental Science and Technology Joint Research Center completed the pilot test of the world’s first project to synthesize biodegradable plastics (PHA) from kitchen waste. Beijing Bennong Environmental Science and Technology Joint Research Center focuses on major problems and technological needs in the field of organic pollution control and restoration in the petroleum and petrochemical industries, and the comprehensive utilization of solid waste organic materials such as kitchen and kitchen waste, and explores new functional degradation and comprehensive utilization in natural and artificial environments. Transform microbial resources, research and develop bioremediation technologies for contaminated sites, cutting-edge technologies and complete sets of equipment for biosynthesis of complex flora, and combine theoretical research with technological process development. The joint research center has accurate positioning, huge development potential and huge space for innovation.
5. Industrial links: The raw material side innovation focuses on green production, and the application side has broad prospects in high value-added fields
In the context of “carbon neutrality”, new production methods are expected to develop into the mainstream path for green synthesis of PHA. In the field of synthetic biology, the entire polymerization process of PHA is carried out at room temperature and pressure. The reaction is safe, the conditions are simple, the carbon emission is low, the specificity is high and the by-products are few, and it has the characteristics of realizing carbon cycle. However, the high manufacturing cost has become the biggest obstacle to the commercialization of PHA by means of synthetic biology. The price of PHA is about 3 times to 10 times that of ordinary polyethylene and polypropylene, which is also the focus of research and development of all PHA companies. Professor Chen Guoqiang of Tsinghua University analyzed the cost structure of PHA biomanufacturing. The cost of substrate raw materials accounts for 50%, the energy consumption accounts for 27%, and the downstream production cost accounts for 23%, which shows that solving the problem of raw material cost is the key to accelerating the commercial process of PHA.
In view of the above problems, optimization and adjustment can be made from three aspects. 1) Use cheap substrates and develop cheap substrate pathways. Develop new substrates with a wide range of sources and low prices, such as food waste treatment, activated sludge treatment, agricultural straw sugar, etc. 2) Continuously improve the performance of the strain and increase the production intensity. Use synthetic biology technology to optimize strains and metabolic pathways, improve enzymatic reaction efficiency, substrate conversion rate, product yield, strain growth rate, and reduce the difficulty of product extraction. 3) Optimize process operation efficiency and improve purification technology. Through model calculation and practice, a whole-process optimization plan is established, so that the entire production process can be operated under the best conditions to achieve the purpose of energy saving and consumption reduction.
PHA has huge application prospects in the fields of high-end medical materials, mid-end packaging materials, low-end express delivery, and disposable products. Thanks to its excellent thermoplastic processability, biocompatibility and biodegradability, PHA is widely used in high-end products. The value-added medical field has broad market prospects.
In the field of textile fibers, the blending of PLA and PHA can significantly improve the heat resistance, antibacterial and anti-mite properties of the fibers, and can be used in the production of antibacterial baby fabrics, antibacterial denim fabrics, antibacterial non-woven fabrics and other products. In the field of packaging materials, because PHA has good compounding properties, PHA can be compounded with other materials, such as compounding with paper to make wrapping paper with special properties, compounding with metal materials such as iron, aluminum, tin, and compounding with fly ash to improve the performance of PHA. Thermal properties and toughness. Can be used for disposable diapers for babies, or some liquid leak-proof packaging, shrink film for packaging metal. In the field of medical materials, PHA is a natural polyester that exists in microbial cells and has good compatibility with the human body. The advantage in the medical field is that it does not need to be removed through secondary surgery. For example, PHB can be completely degraded into 3HB, which is a normal component in human blood, without causing rejection or toxicity. In 2007, P4HB-based absorbable suture (TephaFLEX®) was approved by the US FDA and became the first commercialized PHA medical product.
Business status: market demand is rising, PHA ushered in a golden age of development
In terms of production capacity, although China’s research on PHA started relatively late, it is currently the country that produces the most PHA varieties and the largest output in the world. China has been at the forefront of PHA industrialization, with a planned production capacity exceeding 100,000 tons. Tianjin Guoyun Biotechnology Co., Ltd. has a PHA production line with an annual output of 10,000 tons, and plans to build a 100,000-ton production line in Jilin; Ningbo Tianan Biomaterials Co., Ltd. has a PHA production line with an annual output of 2,000 tons; Green Plastic Technology has also Build a 10,000-ton PHA production base. Ayanite Microbes has started to build a PHA mass production base with a new round of financing. The total production capacity is planned to be 100,000 tons, which will be completed in three phases, of which the first-phase production line of 5,000 tons will be completed and put into operation in 2022. The microstructure factory also completed the 200-ton PHA plant in June 2021, and successfully made fiber spinning with the obtained PHA in July, taking an important step on the road of biosynthetic plastics.
In terms of market prospects and future trends, thanks to PHA’s outstanding performance in material properties, biodegradability, and carbon reduction, the market demand for PHA is growing rapidly. According to the European bioplastic conference data, in 2020, PHA will account for no more than 2% of the global bioplastic production capacity, and by 2025, the proportion of PHA bioplastics will rise to 11.5%, which is similar to the use of PBAT and PLA. It is estimated that the global demand for PHA will reach 10 million tons in the next 20 years, followed by a market of about 300 billion yuan, and the proportion will increase from 2% to 11.5% in the next 5 years.
Currently PHA and related technologies are forming an industrial value chain from fermentation, materials, energy to medical fields. In the future, with the further reduction of cost and the development of high value-added applications, PHA will become a multi-application biomaterial with a cost acceptable to the market, and it will become one of the main development directions of degradable materials in the future.
Compared with other green materials, PHA has the largest price reduction space and adjustable performance. At present, PHA is in short supply in the market, and the price is about 8 times that of traditional petroleum plastics; after mass production, the price may be the same as PLA. As market participants increase, the price of PHA as a commodity will likely decrease. It is foreseeable that with the entry of a large amount of capital, the production capacity of PHA will be further improved, and the worries about the price of raw materials are expected to be resolved. In the medium and long term, reducing the complexity and manufacturing cost of PHA production will help the PHA industry usher in a golden age of development.
Post time: May-09-2022