A new process for production of powder coatings, based on high pressure micronization with supercritical CO2 has been developed. The process enables obtaining of crystalline or amorphous particles with narrow and controllable size distribution and morphology, and has several advantages over existing classical methods, e.g. continuous operating mode, higher capacities, less processing stages, easier cleaning, flexible production, etc.
F.09 Development of a new technological process or technologyCOBISS.SI-ID: 13103894
The solubility of CO2 in polyesters at different temperatures and pressures was measured using a magnetic suspension balance. The solubility data were used for estimating the binary diffusion coefficients. Before and after experiments the polymers were analysed by DSC and XRD in order to determine the glass transition temperature and possible crystallization. Results are crucial for the design and optimization of micronization process and will contribute to better understanding of behaviour of nonideal systems polyester–CO2.
F.02 Acquisition of new scientific knowledgeCOBISS.SI-ID: 12877078
The possibility of obtaining particles and porous structures of polymers by using CO2 as solvent was investigated. The method offers important advantages related to the absence of organic solvents, efficient extraction of solvents, mild processing conditions and the control of particle and foams morphology by simple variation of pressure and temperature. Different polymers and composites and the effects of pressure, temperature and depressurization rate on the final porous structure were investigated. Data about the polymer-CO2 transport properties and phase equilibrium were determined.
F.02 Acquisition of new scientific knowledgeCOBISS.SI-ID: 13171478
The solubility and diffusion coefficients of CO2 in the polymers poly (L-lactide), poly (lactide-co-glycolide) and commercial ß-hydroxyalkyl amide, used as crosslinker, have been determined by the magnetic suspension balance using the gravimetric method. Measurements were performed at different temperatures and pressures up to 30 MPa. Furthermore, the change in the volume was recorded due to dissolution of the gas molecules in matrix. Results show high variations of volumes, high solubility and high diffusion coefficients of CO2 in substances.
F.02 Acquisition of new scientific knowledgeCOBISS.SI-ID: 13927190
Development of a new process for production of powder coatings was based the modified high-pressure PGSS micronization processes. Batch and continuous micronizations of individual components of mixtures, continuous micronizations of mixture without fillers and pigments and micronizations of mixture with fillers and pigments were carried out. The optimal operating parameters of new, high pressure process for production of powder coatings were determined.
F.02 Acquisition of new scientific knowledgeCOBISS.SI-ID: 251045888