Using a chromium catalyst supported on silica gel, ethylene is polymerized under medium pressure in a loop reactor to produce high-density polyethylene.
Processing and application It can be processed by blow molding, extrusion, injection molding, etc. It is widely used in the manufacture of films, hollow products, fibers and daily sundries. In actual production, in order to improve the stability of polyethylene to ultraviolet rays and oxidation, and improve processing and use performance, a small amount of plastic additives must be added. Commonly used ultraviolet absorbers are ortho-hydroxybenzophenone or its alkoxy derivatives, etc. Carbon black is an excellent ultraviolet shielding agent. In addition, antioxidants, lubricants, colorants, etc. are also added to expand the application range of polyethylene. High-pressure polyethylene: More than half is used for film products, followed by pipes, injection molded products, wire wraps, etc.,
Low and medium pressure polyethylene: mainly injection molded products and hollow products.
Ultra-high-pressure polyethylene: Due to the excellent comprehensive properties of ultra-high molecular polyethylene, it can be used as engineering plastics. Price Earnings Ratio (P/E or PER), also known as "price-earnings ratio", "price-to-earnings ratio" or "market-earnings ratio (referred to as P/E ratio)". Price-to-earnings ratio refers to the ratio of stock price divided by earnings per share (earnings per share, EPS). Or divide the company's market value by the annual profit attributable to shareholders.
When calculating, the stock price is usually the latest closing price, and for EPS, if it is calculated based on the published EPS of the previous year, it is called the historical P/E; the EPS estimate used to calculate the estimated P/E is generally based on the market average Consensus estimates, that is, the average or median estimate obtained by the organization that tracks the company's performance and collects the forecasts of multiple analysts. What is a reasonable price-to-earnings ratio does not have certain criteria.
The price-to-earnings ratio is the ratio of the stock price per share to the earnings per share. The market widely talks about the price-earnings ratio usually refers to the static price-earnings ratio, which is usually used as an indicator to compare whether stocks at different prices are overvalued or undervalued. The price-earnings ratio is not always accurate when measuring the quality of a company's stock. It is generally believed that if the price-earnings ratio of a company`s stock is too high, then the price of the stock is in a bubble and its value is overvalued. When a company grows rapidly and its future performance growth is very promising, when the P/E ratio is used to compare the investment value of different stocks, these stocks must belong to the same industry, because the company`s earnings per share are relatively close at this time and comparisons between them are effective.
The price-earnings ratio is one of the most commonly used indicators to assess whether the stock price level is reasonable. It is a very valuable stock market indicator. On the one hand, investors often don`t think that the profit figures calculated in strict accordance with accounting standards truly reflect the company`s continuing operations. Therefore, analysts often make adjustments to the company`s officially announced net profit.
Middle-pressure methods for ceramic molding
2020 11/23