High Efficiency Industrial High Temperature Resistance P84(Polyimide) Fiber Waterproof Film Coated Filter Bag
- Oct 24, 2017 -
The production of pet by this method in industry before 1963 is still widely used in many countries around the world. The method consists of two steps: First, the transesterification of terephthalic acid dimethyl ester (DMT) with ethylene glycol or 1,4-in the presence of catalysts (Fig 1). To produce terephthalic acid hydroxyethyl ester (Bhet) or dibutyl ester, the commonly used catalysts are zinc, cobalt, manganese acetate, or their mixture with antimony trioxide, the dosage is the quality of DMT 0.01%~0.05%.