The dissolution of CO 2 in a polymer causes plasticization of the polymer and hence, its viscosity is reduced. A model based on the free volume theory has been used for a polyester resin, which shows a considerable reduction in the viscosity due to dissolved CO 2. Therefore, supercritical CO 2 has been used as a processing solvent in the continuous production of micron size particles of the resin. Despite the viscosity reduction caused by the dissolved CO 2 , an excess quantity of CO 2 with respect to its solubility limit has been used for micronisation of the polymer due to its high viscosity. The mixing of CO 2 and the polymer has not been possible in an extruder at high gas to polymer mass ratios and consequently, a simplified Kenics type static mixer has been used for the mixing purpose. In this study, the effect of various parameters such as temperature, pressure, nozzle diameter and gas to polymer mass ratio on the particle morphology and size has been studied. The experimental results manifest the technological as well as the theoretical insight into the particles production from a high viscosity material.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.