A novel technique for micronizing PET with compressed THF has been developed. PET pellets were introduced to a high pressure vessel along with THF. When the vessel was closed and heated to 190C, the PET melted. Although several other organic solvents were also able to depress the melting point of PET, only THF was able to facilitate the formation of an emulsion of PET-rich liquid droplets in a THF-rich liquid. In an attempt to generate 100% sub-10micron PET particles, a high speed (5000 rpm) close-clearance impeller was employed to shear the droplets at 200C. While the mixing of the emulsion continued, the emulsion was rapidly cooled. The PET droplets froze at approximately 190 C and the vessel was then cooled to ambient temperature. The PET powder and liquid THF were easily separated via decanting and filtration. Residual THF was easily removed by heating the PET powder to a temperature just above the boiling point of THF. In a typical experiment, the PET particles were less than 5 microns in size. Unlike other SCF-based micronization methods, this method can generate micronized PET without the need for dissolution of PET in THF or rapid expansion of supercritical fluids through nozzles, and can be conducted at relatively high loadings of PET in THF. Further, the micronization can be conducted at the vapor pressure of THF, which is only about 300 psia at the highest temperature employed during the shearing of the emulsion. It does not appear possible generate sub-micron size PET particles, however, with this technique.