Ceramics-Silikáty 42, (4) 164 - 170 (1998)

Syntheses of calcium phosphates from methyl-, ethyl-, i-propyl and n-butyl phosphates and calcium acetate in acidic and basic water-alcoholic solutions were studied. The composition of calcium phosphates depended mainly on the type of the used catalyst. Mixture of hydroxyapatite and β-tricalcium phosphate (β-TCP) was received by reaction of all alkylphosphates with calcium acetate in acidic solution. Calcium pyrophosphate was received when reaction proceeded in the presence of amonium hydroxide. Hydroxyapatite with admixture of calcium pyrophosphate or β-TCP were prepared by means of monoethanolamine or diethanolamine catalysts. It was found that the hydrolysis of P-OR bound played important role in calcium phosphate syntheses. The mechanism of the syntheses was proposed.