Influence of the Processes Parameters on the Properties of The ...

Chapter 2 ........................................................................................................................................................ 27
1 Generalities on Polymer Foams .................................................................................................................... 27
2 Manufacturing <strong>of</strong> Porous Materials by Wet Methods .................................................................................. 28
2.1 Solvent Casting/Particulate Leaching .................................................................................................................... 28
2.2 Ice Particle-Leaching ............................................................................................................................................. 29
2.3 Gas-Foaming/Salt-Leaching Technique ................................................................................................................ 30
2.4 Gel-Pressing Technique ......................................................................................................................................... 31
2.5 PLGA Microspheres for Tissue-Engineered Scaffold ........................................................................................... 32
2.6 Particle-Aggregated Scaffolds Technique ............................................................................................................. 33
2.7 Freeze-Drying Method .......................................................................................................................................... 33
2.8 Thermally Induced Phase Separation (TIPS) Technique ....................................................................................... 34
2.9 Centrifugation Method .......................................................................................................................................... 35
2.10 Injectable Thermosensitive Gel Technique ........................................................................................................... 36
2.11 Liquid-Liquid Phase Separation Technique .......................................................................................................... 37
2.12 Solid-Liquid Phase Separation Technique ............................................................................................................. 38
2.13 Fibre Mesh/Fibre Bondong Technique .................................................................................................................. 38
2.14 Hydrocarbon Templating Technique ..................................................................................................................... 38
2.15 Microspheres Bonding Technique ......................................................................................................................... 39
2.16 Rapid Prototyping Techniques .............................................................................................................................. 39
2.16.1 Three Dimensional Printing (3 DP) ............................................................................................................ 40
2.16.2 Stereolithography (SLA)............................................................................................................................. 40
2.17 O<strong>the</strong>r Derivated Techniques .................................................................................................................................. 41
2.17.1 Combination <strong>of</strong> Leaching <strong>of</strong> a Fugitive Phase and Polymer Precipitation ................................................. 41
2.17.2 Phase-Change Jet Printing .......................................................................................................................... 42
3 Polymer Processing by Supercritical Fluids ................................................................................................. 42
3.1 Bases on Supercritical Fluids ................................................................................................................................ 42
3.2 Basic Techniques in Supercritical Fluids Technology .......................................................................................... 44
3.3 Scaffolds Prepared by Phase Inversion using scCO 2 as Anti-solvent .................................................................... 45
3.4 Scaffolds Prepared by scCO2 Foaming ................................................................................................................. 46
4 Theoretical Background <strong>of</strong> Gas Foaming ..................................................................................................... 48
4.1 Diffusion ................................................................................................................................................................ 48
4.2 Plasticization <strong>of</strong> Polymers by CO 2 ........................................................................................................................ 51
4.3 Nucleation ............................................................................................................................................................. 53
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