Manufacture of porous glass and glass-ceramic particulate structures by gel casting

A process for preparation of porous, bioactive and biocompatible material having a particle size in the range of 200 μto 2500 μm, said process comprising;

• a. melting an admixture comprising a phosphorous compound in an amount of 40 mol % to 60 mol %, a calcium compound in an amount of 30 mol % to 50 mol %, a sodium compound, and at least one other compound,
• said at least one other compound being an oxide of an element selected from the group consisting of titanium, boron, potassium, magnesium, strontium, iron, copper, aluminum, zinc, silver, gallium and cobalt,
• wherein the admixture is free of silicon;
• b. quenching said melted admixture in air or in water, followed by cooling said admixture to obtain a cooled admixture,
• c. crushing and sieving the cooled admixture to obtain a powder comprising particles having a size in the range of 5 μm to 50 μm,
• d. converting said powder into a gel, and casting said gel in a mold, cutting blocks of the cast gel and drying said gel blocks,
• e. sintering said dried gel blocks by:
• uniformly increasing a temperature at a uniform rate to reach a first temperature threshold;
• holding the temperature at said first temperature threshold:
• uniformly increasing said temperature at said uniform rate to reach a second temperature threshold:
• holding the temperature at said second temperature threshold;
• followed by
• cooling the gel blocks to room temperature;
• and
• f. crushing and sieving said sintered gel blocks to obtain the porous, bioactive and biocompatible material having a particle size in the range of 200 μm to 2500 μm and a bulk density in the range of 0.3 g/mL to 0.6 g/mL.