파라디옥사논에 포함된 주요한 불순물인 디에틸렌글리콜을 제거하기 위해, 파라디옥사논과 디에틸렌글리콜과의 이 성분계 고액 상평형 및 혼합물의 밀도를 측정하였으며, 종(seed)을 이용한 경막 용융결정화 실험을 하였다. 얻어진 2성 분계 고액 상평형 결과는 단순 공융계를 형성하였는데, 공용점은 파라디옥사논의 0.08 몰농도에서 246 K였다. 또한, 혼합물의 밀도 데이터는 ρl=k1+k2x+k3T+k4xT 식과 잘 연관되었으며, 각 파라메타인 k1, k2, k3 및 k4의 값은 0.405, 1.361, 0.002, .0.004이었다. 용융결정화 실험에서 결정 성장속도(G)는 냉각속도가 감소하거나 파라디옥사논의 초기농도가 증가할수록 감소하는 경향을 나타내었으며, 결정 성장속도식은 과냉각 온도의 1.5승에 비례하였다. 또한, 불순물의 제거 정도를 나타내는 유효 분배계수(Keff)는 냉각속도 및 PDX 초기농도가 증가할수록 증가하는 경향을 나타내었으며, 유효분배계수는 Wintermantel 모델에 의해 Keff = .0.0604+6.392×Z 관계로 표현되었다. 최종적으로 얻어진 PDX 순도는 결정화 조작변수를 최적화하여 99％ 이상으로 조절할 수 있음을 알 수 있었다.

In order to purify diethylene glycol as main impurity included in p-dioxanone, SLE (solid-liquid equilibria) and mixture density on two components system of p-dioxanone and diethylene glycol were measured and a layered melt crystallization with seed has been applied. The SLE of p-dioxanone and diethylene glycol were a simple eutectic system and the temperature and PDX concentration at eutectic point were 0.08 and 246 K, respectively. Densities of their binary mixtures were well fitted by the best correlation equation, ρl=0.405+1.361x+0.002T.0.004xT. In the melt crystallization, the growth rate (G) was proportional to the 1.5th power of the subcooling degree. The effective distribution coefficient (Keff) as the degree of impurity removal was observed to increase with increasing the growth rate and initial p-dioxanone concentration. And also, Keff was correlated with Z function using Wintermantel’s model such as Keef = .0.0604+6.392×Z. Finally, PDX purity through the optimization of this process can be obtained over 99％.

Layer Melt Crystallization Purification p-Dioxanone Diethylene Glycol Growth Rate Effective Distribution Coefficient Wintermantel’s Model

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