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Development and Prospects of Polymer Chemistry Sun Yu, Kong Xianzhi, Sun Dongzhou, Zhu Tiejun, Wang Zhilu (Heilongjiang Petrochemical Research Institute, Harbin 150040, Heilongjiang) Abstract: This paper reviews the development of polymer chemistry in the 20th century and its important role, and outlines the new trends in its development. Keywords: polymer chemistry ； Outlook ； Three major synthetic materials ； Pollution 1: Polymers include natural polymers and synthetic polymers. It has a close relationship with human life. Over the long course of thousands of years, people have been using natural polymers such as starch and proteins as a source of food to stave off hunger. Wood, bamboo, etc. are used as building materials. The basic structural units of all living matter are also polymers. Due to the limitations in the properties of natural polymer materials, chemical modification of natural polymers emerged by the mid-19th century. In 1939, Americans invented the use of S to vulcanize natural rubber, endowing rubber products with toughness and elasticity, and since then the rubber industry has developed. In 1868, cotton fibers were dissolved in nitric acid to produce nitrocellulose, which was used as a ** and in nitro paints. Cotton fibers are dissolved using NaOH and CS2 to produce rayon, coarse cellulose fibers. Esterify fibers with acetic anhydride to produce rayon, films, coatings, etc. Synthetic polymers were first developed in 1909 when Backeland synthesized phenol-formaldehyde resin to create bakelite plastic. Thereafter, alkyd resin, polyvinyl chloride resin, and urea-formaldehyde resin were synthesized successively. In the 1930s, polystyrene, polyvinyl acetate, polymethyl methacrylate, neoprene, styrene-butadiene rubber, nitrile rubber, and others were successively put into industrial production. At a time when polymer synthetic chemistry is in its infancy, scientific theoretical guidance is urgently needed. In 1920, the German chemist H. Staudinger proposed the concept of macromolecular structure. It laid the theoretical foundation for the field of polymers. Thereafter, the master of polymer chemistry P. J. Flory made outstanding contributions to the theory of polycondensation reactions, the statistical thermodynamics of polymer solutions, and the statistical thermodynamics of polymer conformations, thereby enabling the development of a large number of synthetic polymer compounds. In the 1950s, German chemist R. Ziegler and Italian chemist G. Natta independently invented metal-complexed coordination catalysts to produce low-pressure polyethylene and stereoregular polypropylene. This is undoubtedly an epoch-making invention. In the 1960s, polymer synthetic chemistry, polymer physics, and polymer processing reached a mature stage. This has spurred new developments in polyolefins, synthetic rubbers, and engineering plastics. In the 1970s, rising raw material costs due to the oil crisis temporarily slowed down the development of polymer chemistry. But the problem was resolved quickly. Research on polymers with special functions and the expansion of polymers into biomedical applications have brought polymer chemistry to a brand new stage. In the 1980s and 1990s, polymer chemistry played an important role in the development of various new materials with high performance and multiple functions. A variety of new polymer materials have been developed. 2 The important role of polymer chemistry in various industries Since the mid-20th century, polymer chemistry, particularly the development of the three major synthetic materials—plastics, fibers, and rubber—has progressed at an astonishing rate. 390,000 tons in the 1940s, 2.1 million tons in the 1950s, 9.5 million tons in the 1960s, 41 million tons in the 1970s, and over 100 million tons in the 1980s. It increases by a factor of 5 on average every 10 years. The main reason for the rapid development of these three synthetic materials is people’s living needs. Due to the shortage of natural resources, people have to use synthetic materials as a substitute. The production of the three major synthetic materials has surpassed that of natural resources. Another reason is the abundant availability of raw materials, which is suitable for modern large-scale industrial production. To produce 10,000 tons of natural rubber per year, 100,000 mu of tropical land is required to plant 30 million rubber trees; 50,000 workers are needed each year, and it takes 7–8 years before rubber can be harvested. But only 150 people are needed to produce the same amount of synthetic rubber each year in a factory. Similarly, building a synthetic fiber plant with an annual production capacity of 200,000 tons is equivalent to the output of 4 million mu of cotton fields or 40 million sheep. In various industries, one ton of polymer material can replace 3–7 tons of metal materials. It is widely used in the electronics, electrical appliances, machinery, construction, and agricultural sectors, and has become an essential material for the development of the national economy. 3 Prospects for Polymer Chemistry in the 21st Century by Feng Xinrao. Polymer Bulletin, 1999, (3):1. Feng XD. Preprints of Asia Polymer Symposium. Korea, 1997. Small BL et al. J. C. S., 1998, 120(16):4249. Huang Hetong et al. Advances in Coordination Polymerization of Olefins and Dienes, Beijing Science Press, 1998