The kinetic analysis of the transesterification of dimethyl 2,6-naphthalate(2,6-DMN) with ethylene glycol(EG) was investigated in the presence of various catalysts at 197∼230℃. The degree of reaction was followed by the measurement of output of methanol which was distilled form the reactor. The reactivities of highly basic metal compounds, namely Ca⁺⁺ and Na⁺⁺ were found to be extremely large in the initial stage of the reaction, and to be decreased rapidly with progress of the reaction. However, in the case of metal compounds of lower basicity, especially Za⁺⁺, Pb⁺⁺ etc., such a phenomenon was not observed, and the reactivities were constantly increased throughout the reaction period. The effect of the reactant volume, catalyst concentration, and molar ratio(EG/2,6-DMN) on the reaction rate was studied. The rate equation of the transesterification was assumed to obey second order kinetics with respect to 2,6-DMN and EG and found to be first order kinetics in catalyst concentration as well. Finally, It was found that stability constant was an effective ordering fator as a forecast of catalytic activity for 2,6-DMN and EG.

Demethyl 2,6-naphthalate(2,6-DMN)과 ethylene glycol(EG)을 197∼230℃의 온도범위와 여러 가지 촉매전재하에서 에스테르교환반응시켜 반응속도를 살펴보았다. 이때 반응정도에 따라 반응계에서 부산물로 유출되어 나오는 메탄올의 양을 측정하여 반응도를 평가하였다. 반응초기에는 강염기성 금속화합물(e.g. Na⁺⁺, Ca⁺⁺등)의 반응도가 매우 컸지만, 반응이 진행되어감에 따라 반응도가 급격히 감소하였다. 그렇지만, 이러한 현상은 약염기성 금속화합물(e.g. Zn⁺⁺, Pb⁺⁺등)의 경우에 있어서는 관찰되지 않았고, 반응이 진행되는 동안 반응도는 지속적으로 증가하였다. 또한, 반응물의 체적, 촉매농도, 그리고 반응매개물간의 몰비(molar ratio)를 고려하여 반응속도식을 연구한 결과 반응차수가 2,6-DMN과 EG에 대해서는 각각 1차이며, 또한 촉매농도에 대해서도 1차임을 알았다. 최종적으로, 안정화상수는 2,6-DMN과 EG에 대한 촉매활성을 예측하는 효과적인 지표인자(ordering factor)임을 알았다.

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