Crude oil is the "blood" of modern industry, and its cracked refined oil provides kinetic energy for vehicles, and asphalt is the basic raw material for infrastructure construction. Even the clothes we wear, the water pipes at home and the plastic bags when shopping are all produced by the downstream products of crude oil. Due to the wide use of crude oil, in modern society, any country and individual can not do without crude oil.

With the increasing dependence of human beings on crude oil, the price or supply of crude oil has become a problem that must be solved by major economies. Especially in previous years, the international crude oil price remained at a high level of 80- 1 10 USD/barrel, which restricted the economic development. In addition, the situation in the Middle East, the world's largest crude oil producing area, is unstable, and major economies are beginning to find solutions to high oil prices. In order to obtain a stable supply of low-priced crude oil, China and the United States have the same idea, that is, "do it yourself and have plenty of food and clothing".

Ethylene is a very basic chemical raw material, which is mainly cracked from petroleum, so the fluctuation of crude oil has a great influence on the price of ethylene. In addition, the main product of coal chemical industry is coal to olefins, that is, coal to ethylene The solution to the problem of high oil prices in China and the United States "pits" plastics. First, the rise of shale oil technology has caused the increase of crude oil supply, and the collapse of crude oil price has directly led to the collapse of plastic cost; Secondly, the rise of coal-to-olefin technology in China has increased the supply of raw materials for plastics. Under the attack of shale oil and coal to olefins, the plastic futures price, known as natural bulls, was "defeated" and the support of 9000 yuan/ton was ruthlessly broken.

With the collapse of crude oil prices, the coal-to-olefin industry has been hit hard. When the price of crude oil is above $80/barrel, coal chemical industry has a cost advantage. Driven by interests, a large number of coal chemical plants have been put into production. At present, when the price of crude oil falls below $80/barrel, the cost advantage of coal chemical industry no longer exists. Especially when the price of crude oil falls below $60/barrel, the cost of coal chemical equipment is obviously higher than that of petrochemical industry, which leads to a sharp drop in the start-up load of coal chemical equipment, a delay in the commissioning of equipment, and a temporary suspension of planned equipment. In addition, although the petrochemical industry has advantages over the coal chemical industry at present, the market generally believes that crude oil prices are difficult to stay at a low level for a long time. In addition, the investment of ethylene integrated devices is tens of billions of yuan, and the time period needs several years. These funds are very cautious about the commissioning of petroleum-based ethylene plants. Coal chemical industry is constrained by low oil prices, and petrochemical industry is worried about the cycle of low oil prices. In this case, the supply of plastics in the chemical industry is relatively short, and it is difficult to significantly increase the supply in the short term.

To sum up, when the price of crude oil is 60-80 USD/barrel, low oil price will not only cause the collapse of plastic cost, but also inhibit coal chemical industry. Once the price of crude oil is below $60/barrel, coal chemical industry will basically be squeezed out of the market, and the impact of further oil price decline on plastics will become a simple cost reduction. By then, the relatively resistant chemical plastic may begin to lead the decline.