Hydrothermal synthesis of calcium-deficient hydroxyapatite whiskers and their thermal transformation to polycrystalline β-tricalcium phosphate short fibers. Issue 1 (1st March 2013)

• Record Type: Journal Article
• Authors: Gbureck, Uwe; Mitró, Daniel; Zorn, Katharina; Müller, Frank A.; Vorndran, Elke
• Is Part Of: Bioinspired, biomimetic and nanobiomaterials. Volume 2:Issue 1(2013)
• Page Start: 11
• Page End: 19
• Publication Date: 2013-03-01
• Subjects: biomaterial; -- synthesis; -- material chemistry; -- material structure; -- apatite; Biomimetic materials -- Periodicals; Nanobiotechnology -- Periodicals; Biotechnology -- Periodicals; 660.605
• DOI: 10.1680/bbn.12.00019
• Languages: English
• ISSNs: 2045-9858

Abstract

Abstract : Resorbable calcium phosphate fibers are of particular interest to reinforce biodegradable bone substitutes for load-bearing applications. The aim of the present study was to prepare calcium-deficient hydroxyapatite (dHAp) whiskers with a molar Ca/P ratio of 1·5 by a hydrothermal synthesis and to transform them to β-tricalcium phosphate (β-TCP) by a subsequent thermal treatment. For the hydrothermal synthesis, calcium tripolyphosphate was used and different amounts of 2-propanol were added to adjust the pH. Average whisker lengths of 160 μm were obtained at a 2-propanol content of 27 volume-percent. However, 33% dicalcium phosphate anhydrate (DCPA) were present as a secondary phase. The amount of DCPA could be reduced by increasing the amount 2-propanol. Whisker samples consisting of 88% dHAp and 12% DCPA were selected to investigate microstructural changes and phase transformations during thermal treatment. Polycrystalline single phase β-TCP short fibers were obtained after a thermal treatment at 1125°C. Resorbable calcium phosphate fibers are of particular interest to reinforce biodegradable bone substitutes for load-bearing applications. The aim of the present study was to prepare calcium-deficient hydroxyapatite (dHAp) whiskers with a molar Ca/P ratio of 1·5 by a hydrothermal synthesis and to transform them to β-tricalcium phosphate (β-TCP) by a subsequent thermal treatment. For the hydrothermal synthesis, calcium tripolyphosphate was used and different amounts of 2-propanol were added to adjust the pH. Average whisker lengths of 160 µm were obtained at a 2-propanol content of 27 volume-percent. However, 33% dicalcium phosphate anhydrate (DCPA) were present as a secondary phase. The amount of DCPA could be reduced by increasing the amount of 2-propanol. Whisker samples consisting of 88% dHAp and 12% DCPA were selected to investigate microstructural changes and phase transformations during thermal treatment. Polycrystalline single phase -TCP short fibers were obtained after a thermal treatment at 1125°C.