/kloc-from the middle of 0/8th century to the beginning of 20th century, the chemical industry was in the primary stage. At this stage, inorganic chemical industry has begun to take shape, organic chemical industry has begun to take shape, and polymer chemical industry has begun to take shape. After the development of textile industry, natural dyes can no longer meet the needs. With the development of iron and steel industry and coking industry, it is necessary to utilize the by-product coal tar. Chemists have separated coal tar into,, anthracene, phenanthrene and so on. Based on the achievements of organic chemistry. 1856, the British synthesized aniline violet dye, and then the structure of natural alizarin was determined to be dihydroxy anthraquinone through analysis. Then, anthracene in coal tar was used as raw material to simulate with natural alizarin through oxidation, substitution, hydrolysis and rearrangement. Pharmaceutical industry and perfume industry have also synthesized the same chemical substances as natural products, and the varieties are increasing day by day. 1968+0867, Swedes invented explosives (see), which are widely used in mining and military industry.

At that time, there was another pillar in the production of organic chemicals, namely acetylene chemical industry. 1895 established the first factory to produce calcium carbide (acetylene) from coal and limestone. Calcium carbide is hydrolyzed to produce a series of basic organic raw materials such as acetaldehyde and acetic acid. After the development in the mid-20th century, the energy consumption of calcium carbide was too high, and most of the original acetylene products were produced as raw materials. It becomes sticky when heated. Hardened by cold. 1839, the United States used sulfur to heat natural rubber to crosslink it into elastomer, which was widely used in rubber products such as tires. This is the embryonic period of polymer chemical industry. 1869, the United States made plastics from nitrocellulose plasticized with camphor, which is of great value. 18965438, the first man-made project was built in Besancon.

These budding products are far from meeting the requirements of society in variety, yield and quality. Therefore, since the establishment of petrochemical industry, great progress has been made in the production of the above basic organic chemicals and polymer materials.