Abstract
The acid-catalyzed hydrolysis reaction of poly(vinyl acetate) (PVAc) in water/acetic acid solution at $35^{circ}C$ was studied at two different solvent compositions. The mole fractions of vinyl acetate (Vac) and vinyl alcohol (VA) during the course of the reaction were determined by NMR, and the equilibrium constant $K_{eq}$ of the reaction was determined using the molar ratio of VAc to VA at the chemical equilibrium. $K_{eq}$ was 0.75 (${\pm}0.01$) when the VAc mole faction at the equilibrium was 0.78 (${\pm}0.01$) and it was 0.69 (${\pm}0.01$) when the VAc mole fraction was 0.57 (${\pm}$0.02). The reaction was found to be a pseudo 1-st order reaction with the rate coefficient at $3.4{\times}10^{-6}/sec$.
산을 촉매로 한 물/초산용액에서의 폴리(비닐 아세테이트) 가수분해반응을 $35^{circ}C$에서, 물과 초산치 비율을 달리한 두 용액 조성에서 연구하였다. 반응시간에 따른 비닐 아세테이트(VAc)와 비닐 알코올(VA) 단량체 몰분율을 NMR로 측정하였고, 반응이 평형에 도달한 후의 화학평형상수($K_{eq}$)를 화학평형상태에서의 VAc와 VA의 몰분율을 이용하여 결정하였다. 화학평형에서의 VAc 몰분율이 0.78(${\pm}0.01$)이었을 때 $K_{ef}$는 0.76(${\pm}0.01$)이었고, VAc 몰분율이 0.57(${\pm}0.02$)일 때 0.69($\{pm}0.01$)이었다. 가수분해반응은 가성 1차 반응을 따랐으며, 반응속도상수는 $3.4{\times}10^{-6}/sec$이었다.