High-Pressure Phase Behavior for Poly(ethylene glycol) and 1,1,1,2-Tetrafluorethane Systems

MENESES, MARCELA OLIVEIRA; DARIVA, CLAUDIO; BORGES, GUSTAVO RODRIGUES; DA ROCHA, SANDRO R. P.; ZABALOY, MARCELO SANTIAGO; FRANCESCHI, ELTON

JOURNAL OF CHEMICAL AND ENGINEERING DATA

AMER CHEMICAL SOC

Lugar: Washington; Año: 2017 vol. 62 p. 1853 - 1858

0021-9568

The development of polymeric systems for drug deliveryhas received attention with the aim of producing new systems as analternative to conventional drug therapy. The design of new systems forthis purpose in a compressed medium requires a knowledge of thephase behavior for the polymeric matrix in the high-pressure fluids. Thiswork reports the phase equilibrium experimental data of binary systemsinvolving poly(ethylene glycol) (PEG) with molecular weights of 1000and 2000 g·mol−1 and 1,1,1,2-tetrafluoroethane (HFA-134a). Theexperimental data were obtained in a high-pressure variable-volumeviewing cell based on the static synthetic method at temperatures from287.4 to 334.2 K, pressures of up to 29.81 MPa, and a PEGconcentration in the range of 1 to 7 wt %. Liquid−liquid equilibrium,liquid−liquid−vapor equilibrium, and, in some cases, solid−liquid equilibrium were observed under the experimental conditionsof pressure, temperature, and compositions investigated. The experimental results show that temperature and pressure havesignificant influences on the solubility of PEG in HFA-134a. The solid-phase formation for the system PEG + HFA-134a, in therange of values investigated for temperature, pressure, and compositions, is influenced by the molecular weight of the polymer.