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利用低温水溶液均相沉积法制备了磷酸钙盐微纤维;应用原位沉析法制备了壳聚糖(CS)三维棒材及羟基磷灰石(HA*)/CS复合棒材。XRD证实应用原位沉析法制备HA*/CS复合棒材过程中,磷酸钙盐转化为羟基磷灰石结构,尺寸为10~60μm,并用SEM对晶体形貌进行了表征,分析了转化机制。HA*/CS复合材料的微观形貌表明,HA*晶体在CS凝胶棒原位沉析的过程中析出而与CS基体形成镶嵌、相互咬合结构,且在基体中分散均匀,有效地提高了HA*与CS基体的界面连接作用,使力学性能显著提高。所制备的HA*/CS棒材随HA*含量的增大(在其饱和溶解度3.3 wt%范围内),复合材料的弯曲性能逐渐提高,当羟基磷灰石质量分数为3.3%时,复合材料的弯曲强度达到159.6 MPa,弯曲模量达到5.1 GPa,比CS基体分别提高85.6%和54.5%。HA*/CS复合棒材的弯曲强度和弯曲模量远高于松质骨,弯曲强度也比密质骨高。
The calcium phosphate microfibrils were prepared by homogeneous deposition of low temperature aqueous solution. Chitosan (CS) three-dimensional bar and hydroxyapatite (HA *) / CS composite bar were prepared by in situ precipitation. XRD showed that during the preparation of HA * / CS composite rods by in-situ precipitation method, calcium phosphate was converted to hydroxyapatite structure with the size of 10 ~ 60μm. The crystal morphology was characterized by SEM. The mechanism of transformation was analyzed . The microstructure of HA * / CS composites shows that the HA * crystals are precipitated during the in-situ precipitation of the CS gel rod and form inlaid and intermeshing structures with the CS matrix, and are uniformly distributed in the matrix and effectively improve HA * interface with the CS substrate interface, so that mechanical properties significantly improved. The flexural properties of the prepared HA * / CS rods increased with the content of HA * (within the range of 3.3 wt% of their saturated solubility), and the bending properties of the composites increased gradually. When the mass fraction of hydroxyapatite was 3.3% Flexural strength reached 159.6 MPa and flexural modulus reached 5.1 GPa, 85.6% and 54.5% higher than the CS matrix respectively. The flexural strength and flexural modulus of HA * / CS composite rods are much higher than those of cancellous bone, and their flexural strength is also higher than that of dense bone.