The transesterification of dimethyl terephthalate (DMT) with 1,3-propanediol (PDO) was investigated in the presence of catalyst, titanium (IV) butoxide (TBO), at 175~190 ℃ . The degree of transesterification reaction was measured by the output of methanol which was distilled from the reactor. The amount of methanol increased as the reaction temperature, molar ratio and catalyst concentration increased. The observed overall rate of the transesterification was third order; first order with respect to DMT, PDO, and the concentration of catalyst, respectively. Using calculated rate constants, the activation energy for transesterification was 26.93 kcal/mole. The melting temperature of bis(2-hydroxytrimethyl) terephthalate (BHTMT) was 85.2℃ and heat of fusion 141.3 J/g.

디메틸 테레프탈레이트(DMT)와 1,3-프로판디올(PDO)을 175~190 ℃ 사이의 일정 온도에서 티타늄부톡사이드(TBO) 촉매를 사용하여 에스테르교환반응 속도에 대해서 조사하였다. 에스테르교환반응 정도는 반응기 밖으로 유출되어 나오는 메탄올의 양으로 결정하였으며, 메탄올의 수득률은 반응온도, PDO/DMT의 몰비 및 촉매농도가 증가할수록 증가하였다. 반응차수는 DMT, PDO 및 촉매의 농도에 대해 각각 1차 반응이며, 총괄차수는 3차 반응이었다. 반응속도상수로 계산된 활성화에너지는 26.93 kcal/mole 이었으며, 생성된 비스(2-히드록시트리메틸)테레프탈레이트(BHTMT)의 용융온도는 85.2 ℃, 용융열은 141.3 J/g 이었다.

Keywords: dimethyl terephthalate (DMT); 1,3-propanediol (PDO); transesterification; kinetic; bis(2-hydroxytrimethyl)terephthalate (BHTMT)