Molecular Design of Chemical Synthesis of Biodegradable Polymer Compounds

Chemically Synthesized Biodegradable Macromolecules in Molecular Design Wu Xueming, Zhao Yuling, Wang Xichen (School of Chemical Engineering, Beijing Technology and Business University, Beijing 100037, China) The use of molecular design methods to develop novel biodegradable polymers, chemically synthesized polymers It can meet the requirements of use and can be assimilated with the natural environment after being discarded due to biological degradation.

: The injury in 2001 severely hindered social progress and sustainable economic development. China’s macroeconomic decision-making has included the degradation of polymers as a priority area for high-tech industrialization with national priorities. According to recent foreign reports, Japan, the United States, and Europe are all strengthening the research and development of degradative polymers and accelerating the process of practical application. As a natural biodegradable material, biodegradable polymer has played a unique role in environmental protection and has become one of the research hotspots. Although natural macromolecules and microbial synthetic macromolecules have good biodegradability, they have poor mechanical properties or high price; chemical synthesis of such macromolecules, if they still adopt the traditional trial and error method for synthesis screening, the workload is large and time-consuming. low efficiency. Moreover, with the continuous improvement of the intellectual property system and the ever-increasing demand for ecological environment, the development of new polymers has become more difficult, the success rate of screening has been reduced, and the required expenses are staggering. This heavy pressure has forced industry and academia to seek rapid economic growth. The development method 111. In order to achieve the unity of degradability, practicality and economy, many foreign research institutions and companies have begun to use molecular design methods to synthesize biodegradable polymers.

The concept of a molecular design is very attractive, and its basic concept is. Among them BAK1095 polyester amide.

The Czech Academy of Sciences proposes that poly-fatty esters/polyarylate copolymers can be synthesized using the special properties of peptide bonds. The peptide bond itself can be acted on by a peptide bond endase and a peptide bond end enzyme. When the peptide bond is broken down, the microorganisms will randomly act on the remaining matrix molecules to decompose these molecules. Based on this property of the peptide bond, poly-N-(2-hydroxyethyl)-1-glutamine (PHEG) can be reacted with P-related phenyl-containing monomers to produce P (HEG-ran-phe some functionalities Side-group cyclic lactones undergo ring-opening polymerization and subsequent reactions to synthesize biodegradable polyesters with pendant functional groups.Polyesters with pendant carboxylic acid groups are known as self-degradable polyesters and pendant carboxylic acids. Participation accelerates the hydrolysis of ester bonds in the main chain, making their biodegradation easier. 112. Some polyesters with carboxylic acid side groups have been synthesized.

The ~ 161 malonolactone-benzyl ester undergoes ring-opening 1 polymerisation 2 hydrogenolysis polymerization followed by hydrogenolytic cleavage of the -benzyl group to give poly(-malic acid) as shown.

The ring-opening polymerization of malate lactone-benzyl esters into poly (P-malic acid) chemical processes 4.3 Synthesis of polymers with degradability and good overall performance Biodegradability, melting point, hardness according to various monomers , Hydrolysis performance, etc. are properly polymerized to synthesize polymers with good overall performance. BASF is also developing degradable polyester copolymers. 19. Using ring-opening polymerization methods from glycolic acid (actually with chloroacetic acid) and lactic acid. The monomer-polymerized poly(lactide) (PLEG) has the advantages of two kinds of polyester, its crystallinity is greatly reduced, the mechanical properties are improved, and the biodegradation rate is also improved. The reaction process is as shown. HaeSangun et al. expressed the good mechanical properties of PCL/PET (polyfatty ester/polyaromatic ester) structures produced by transesterification of polycaprolactone (PCL) and polyethylene terephthalate (PET). When the content of PET is less than 50%), it can be degraded by lipase. The (salt)-structured monomers in the newly synthesized degradable plastics from DuPont can produce biodegradable polyester/poly(phenyl)ester polymers with a certain amount of methacrylate. .

Such polymers have reduced bio-degradability and good use performance while at the same time reducing costs, and have good economic benefits and development prospects.

5 Outlook According to the actual performance requirements, the design of polymer structures at the molecular level shows an infinitely broad future. Catalyst technology has made great progress, the most prominent of which is the metallocene catalyst, which is soluble in hydrocarbons, has only one activation point, and rapidly changes its chemical structure.

It can precisely adjust the molecular chain length, branching, and isotacticity in the production of polyolefins. Therefore, the molecular configuration can achieve tight control, and the physical properties and processing performance of the polymer are closely related to the molecular structure. The product can be produced with the required properties. A series of non-metallocene catalysts developed by DuPont in collaboration with the University of North Carolina can provide greater flexibility in the degree of polymer branching and copolymerization, and the resulting polymers have more precise structures. The latest developments in chemical technology (IV). China Chemical Information, 1999 (46):13. 2. Shanghai: Shanghai Science and Technology Press, 1981: 1-2. 5 Huang Hairong. The current status of development of biodegradable polymer materials. Chemicals Tian Tianyi Kai, Hou Liying, Yu Xiaodong, et al. Development and modification of foreign biodegradable polymers. Shanghai Chemical Industry, 199924 (7).

Lin Xing. Bayer's development in the field of polymer materials. China's Bu Weiwen. Biodegradable thermoplastic BAK1095. Chemicals Wu Ying, Guo Shiming, Tang Wen. Biodegradable Poly-Cold Ethylene Acrylic Synthesis and Research. New chemical materials, 200028 (1) 24 horse actually. A list of the world's degradable plastics. China Chemical Information, 1999, Yang Huixi. Biodegradable plastics development status and development trend. China Plastic Zhu Zenghui. The latest progress in chemical technology (1). China Chemical Information, (Continued from page 33) (Edit this article SXQ)