Application of Phosphate Based Inorganic Compounds to Biomedical, Life, and Environmental Materials

我们已经研究了磷酸盐基无机化合物在生物医学、生命和环境材料中的应用。这项研究的一些结果如下所示。(1)以聚丙烯酰胺、聚甲基丙烯酸甲酯、丙烯酰胺为单体，制备磷酸钙水硬性固化体。羟基磷灰石的热分解产物α-Ca_3（PO_4）_2、β-Ca_3（PO_4）_2和无定形磷酸钙被用作磷酸钙骨水泥。所得磷酸钙硬化体的体积密度约为1.7，抗弯强度为11-12 MPa，与不加聚合物时所得硬化体相比，抗弯强度提高了一倍。(2)我们已经发现，加速和减速的类骨晶体生长在模拟体液溶液中的极化陶瓷和涂层的羟基磷灰石，取决于电极化条件。晶体的生长依赖于直流电场强度、温度和极化时间。在带负电荷的表面上观察到加速的晶体生长，而在带正电荷的表面上从未发生过晶体生长。分析结果表明，部分碳酸化的羟基磷灰石钙的骨样晶体的形成。目前的结果有望大大有助于仿生羟基磷灰石涂层方法的发展植入材料。

We have been investigated on application of phosphate-based inorganic compounds to biomedical, life, and environmental materials. Some results of this research are shown below.(1) Preparation of hydraulic hardened bodies of calcium phosphates was carried out adding polyacrylamide, polymethylmetacrylate, and monomer of acrylamide. Hydrolysis of calcium phosphates was remarkably by the above additives at room temperature and accelerated above 80ﾟC.Thermal decomposition products of hydroxyapatite, alpha-Ca_3(PO_4)_2, beta-Ca_3(PO_4)_2, and amorphous calcium phosphate were used as calcium phosphate cements. The calcium phosphate hardened bodies obtained were found to be about 1.7 in bulk density and 11-12 MPa in bending strength, which was doubled compared with that obtained on no addition of polymers.(2) We have discovered the acceleration and deceleration of bone-like crystal growth in simulated body fluid solution on polarized ceramics and coatings of hydroxyapatite, depending on the electric polarization conditions. The crystal growth was dependent upon the dc field strength, temperature, and time for polarization. The accelerated crystal growth was observed on negatively charged surfaces, whereas no crystal growth ever took place on the positively charged surface. The analytical results indicate the formation of bone-like crystals of partially carbonated calcium hydroxyapatite. The present result is expected to greatly contribute to the development of biomimetic HAp coating methods on implant materials.