Polyethylene terephthalate(PET) with high molecular weight is hard to be obtained due to the backward reaction of the global equilibrium reaction. As the reaction proceeds especially for the final stage of PET synthesis, the tremendous increase in viscosity prevents removal of the byproduct so that it is difficult to reach the high degree of polymerization. Many reactors have been developed to resolve this problem and are presently used in industry, but it is still interesting to see the other types of reactor to enhance the efficiency of the process. In this study to enhance the efficiency of polymerization, Rotating Drum Reactor was developed and its efficiency was tested. Bis-2-hydroxy ethyl terephthalate(BHET) monomer was fed into the reactor, where temperature was kept 280℃. Then volatile byproduct (EG) is continuously removed from the reaction mixture by controlling the pressure. Catalyst used was Sb₂O₃ and stabilizer was not used. Good result is obtained with proper surface renewal action by rotating the outer cylinder which was found to be the most important factor to remove the volatile byproduct. As espected reactor efficiency increases with decreasing the surface renewal time. The effect of vacuum pressure on the reactor efficiency was also tested.

Polyethylene terephthalate(PET) 중합반응은 기본적으로 평형반응으로서 부산물 제거 없이는 높은 분자량을 얻기가 힘들고, 특히 마지막 단계에서는 반응이 진행됨에 따라 반응 혼합물의 점도가 급격히 증가하여 부산물의 제거가 더욱 어려워지고 결국 우리가 얻고자하는 높은 분자량을 얻기가 힘들어진다. 본 연구에서는 이러한 문제를 해결하기 위해서 rotating drum 반응기를 개발하였고 그 효율을 알아 보았다. Bis-2-hydroxy ethylterephthalate(BHET)단량체가 온도 280℃로 유지되고 있는 반응기로 주입되고 반응기 압력이 조절되면서 생성된 부산물이 반응 혼합물로부터 연속적으로 제거된다. 촉매로는 Sb₂O₃를 사용하였고 안정제는 사용하지 않았다. 휘발성 부산물을 제거하는데 가장 유효한 인자로 알려진 film 재생성을 반응기 겉통을 적절히 회전시킴으로서 얻을 수가 있었고 기대했던 대로 film 재생성 주기를 줄임으로서 반응기 효율의 증가를 보였다. 또 반응기 효율에 진공도가 주는 영향을 알아보았다.

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