Investigation of structure formation during freeze-casting from very slow to very fast solidification velocities

Crystal Templating with Mutually Miscible Solvents: A Simple Path to Hierarchical Porosity

“…The largest macropores present a facetted morphology typical of TBA-templated materials 15 . The eutectic A in the water/TBA system (trajectory c in Figure 1) yields lamellar pores with a short spacing (1-3 µm, figure 3A), a range that has been difficult to achieve thus far in the other ice templating systems 16 .…”

“…The resulting structure comprises thus just two populations of macropores ( Figure 3B), created respectively by the large ice crystals and the packing of particles. The final materials comprise polycrystalline platelets of large dimensions (10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20) µm in thickness, and hundreds of microns in length and width).…”

Spatiotemporally Controlled Microchannels of Periodontal Mimic Scaffolds

“…According to recent studies on controllable crystal growth kinetics and fabrications of directional porous architectures (Deville et al, 2006a;Waschkies et al, 2011), freezing temperature, freezing time, and freezing rate are significant factors that influence crystal formation and microstructure morphologies (Li et al, 2012). Because the rapid freezing process solidified different phase materials simultaneously (paraffin and gelatin at 20°C), it was difficult to control the direction of ice crystal growth with liquid nitrogen in our paraffin-gelatin system.…”

“…Freeze-casting is a simple approach to create submicron-level porous constructs via aqueous materials (Deville et al, 2006a;Ma et al, 2010;Waschkies et al, 2011). Freezing conditions can control microscopic patterns of ice crystals, and the regularity of ice growth can provide unidirectionally or radially oriented pores within the internal architectures of scaffolds (Deville et al, 2006b;Ma et al, 2010;Li et al, 2012).…”

Structure and mechanical properties of β-TCP scaffolds prepared by ice-templating with preset ice front velocities

“…For suspensions of solid particles with a size of 2 µm this is in the range of 0.5 µm/s [15] to 200 µm/s [16]. Hence, the range of pore widths is also limited -for example in the case of alumina pore widths of a few µm [14,15] up to several 100 µm were obtained [17]. Deville et al showed, that ice-templated hydroxyapatite exhibit more than three times higher compression strengths than scaffolds of the same material with the same porosity prepared by other methods [12,18].…”