摘要 |
1,223,378. Continuous process for making polyethylene terephthalate. ASAHI KASEI KOGYO K.K. 23 April, 1969 [24 April, 1968], No. 20772/69. Heading C3R. [Also in Division B1] Bis - # - hydroxy - ethyl terephthalate is polymerized by mixing it with antimony trioxide and phosphorous acid, and then passing the mixture down through the reactor shown, of which the outlets 3 from each chamber 5 are orientated as in Fig. 2 to produce rotating currents in the next lower chamber 5. Ethylene glycol vapour is drawn off at 7. In the embodiment of Fig. 4 (not shown), the outlet at the bottom of the reactor leads to a centrifugal separator to separate the vaporized by-products from the polymerized liquid. |