Unsaturated polyester production technology Before the 1970s, the improvement of polyester production technology was mainly feeding and discharging automation, increasing the volume of the kettle and the quality of undetermined products. Recently, a new technology for producing polyester with propylene oxide instead of propylene glycol has been invented. The main advantages of this new technology are: the polycondensation reaction does not produce by-products; the production cycle is more than doubled by the propylene glycol method; and the variable batch operation is continuous operation.
The law is currently industrialized in Europe, America and Japan. my country's Tianjin Synthetic Material Factory has also been put into working production in June 1975.
According to reports, each RCI company has used this method to continuously produce polyester.
The glass fiber reinforced plastics produced by pre-forming technology mainly have sheet mold plastic boxes and bulk mold plastics, and the annual output increases at a rate of more than 20%. It was first produced by Bayer West Germany, and later in Western Europe, the United States and Japan have also been put into production. In 1947, it provided conditions for continuity and mechanization in the international market, and had important influences on working hours, costs, raw material consumption, and product quality.
my country's research and development work has achieved initial results. Beijing 251 Factory has built a 200-ton/year sheet-shaped plastic passenger train. This is a promising new process. The emergence of this method will definitely accelerate the development of the polyester industry. In addition, the successful development of corrugated tile continuous production units and CNC winding units has also made the development of China's FRP molding process reach To a new level.