The earliest history of polyester series products, it can be said that in 1928, Carothers of DuPont Company of the United States studied the polycondensation of polyester color yarn Manufacturers and ethylene glycol, and the earliest made fiber from polyester. In the autumn of 1931, Carothers (Carothers) officially published its research results in the American Chemical Society. The fiber has silk luster, strength and elasticity are comparable to silk, but because of its low melting point, easy hydrolysis and alkali resistance, it has no practical value. But this study first confirmed that polyester can be made into fibers. In 1941, Winfield and Dickson of the British Calico Printing and Dyeing Workers Association (hereinafter referred to as CPA), inspired by the work of Carothers, continued to study polyester, and CPA obtained a patent in 1942. It can be said that polyester (PET) was the first to achieve industrial production in the UK in 1949. Because of its excellent consumption and high strength, it has become the largest variety of synthetic fibers.
Polyester route includes direct esterification method (PTA method) and transesterification method (DMT method). The PTA method has the advantages of low raw material consumption and short reaction time. Since the 1980s, it has become the main process of polyester and the preferred technical route. The rug mat yarn Manufacturers is a continuous production process, and the semi-continuous and intermittent production processes are suitable for small and medium-sized production devices. The continuous process of the PTA method mainly includes several technologies such as the German Zimmer company, the American DuPont company, the Swiss Inventa company, and the Japanese Konebo company.
Among them, the technology of Jima, Yvonda, and Zhongfang is a 5-kettle process, and DuPont has developed a 3-kettle process (currently developing a 2-kettle process). The polycondensation process is basically similar, the difference is the esterification process. For example, the 5 kettle process uses lower temperature and pressure esterification, while the 3 kettle process uses a high ethylene glycol (EG)/PTA molar ratio and a higher esterification temperature to strengthen the reaction conditions, speed up the polyester DTY Manufacturers, and shorten the reaction time.