亚微米羟基磷灰石/聚乳酸复合材料的制备及形貌分析

背景：聚乳酸同纳米羟基磷灰石制备骨组织工程支架材料有良好的生物相容性，但是纳米级羟基磷灰石易团聚、很难均匀分散在材料中，使无机粒子和有机高聚物之间的结合状况受影响。目的：制备亚微米羟基磷灰石/聚乳酸复合材料，探讨聚乳酸溶液浓度、羟基磷灰石在溶液中的分散时间及羟基磷灰石含量对其在聚乳酸基体中分散性的影响，并分析复合材料的表面形貌、断面、复合材料界面状况。方法：采用溶液共混的方法，借助超声波分散技术，将亚微米羟基磷灰石以不同比例分散于溶剂为氯仿的聚乳酸溶液中，而后在室温下除去混合体系中的氯仿制得不同含量的亚微米羟基磷灰石/聚乳酸复合材料。观察不同溶液浓度对亚微米羟基磷灰石在溶液中的分散性的影响。借助扫描电镜、红外光谱分析亚微米羟基磷灰石/聚乳酸复合材料的断面、界面状况。 结果与结论：在亚微米羟基磷灰石/聚乳酸复合材料质量比为0.15:1，分散时间大于30 min，聚乳酸溶液浓度为0.14 kg/L时，可使得羟基磷灰石在该浓度下有着较好分散性；而当亚微米羟基磷灰石含量超过15%就会在复合材料中产生团聚；红外分析表明，溶液共混制备的复合材料中亚微米羟基磷灰石/聚乳酸复合材料其特征官能团的位置没有发生变化。表明：借助超声波振荡的方法，可实现亚微米亚微米羟基磷灰石与聚乳酸复合材料较好的溶液共混，有望提高复合材料的界面状况。关键词：亚微米羟基磷灰石；聚乳酸；复合材料；生物相容性；组织工程doi:10.3969/j.issn.1673-8225.2010.29.019

Preparation and surface morphology analysis of submicron nano-hydroxyapatite/poly L-lactic acid composites

BACKGROUND: Nano-hydroxyapatite (HA)/poly L-lactic acid (PLLA) composites as scaffold material in bone tissue engineering have good biocompatibility. However, HA is characterized by easy agglomeration and hard equably dispersed in materials, the combination between inorganic particle and organic high polymer is affected. OBJECTIVE: To prepare HA/PLLA composite, and study the effect of PLLA solution, the disperser time of HA, the content of HA on dispersion, and analyze the surface appearance, the cross section and the interface of HA/PLLA composites.METHODS: Sub-micron HA/PLLA composites was prepared by the method of the solution blending, submicron HA powder was dispersed into the chloroform solution of PLLA with the aid of the ultrasonic wave, and then the mixed system was dried under the natural condition to remove the solvent, finally the submicron HA/PLLA compound materials was obtained. The effect of the solution concentration on dispersion HA in solution was discussed. The cross section of composites and interface were analyzed by the Fourier transform infrared spectroscopy and the scanning electron microscopy. RESULTS AND CONCLUSION: When the mass ratio of sub-micron HA to PLLA was 0.15: 1 and dispersing time HA in PLLA solution exceeded 30 minutes. PLLA solution 0.14 kg/L can make HA good dispersity in PLLA. When sub-micron HA content exceeds 15%, it will produce reunion in composite materials. Infrared analysis shows that characteristic functional groups from HA/PLLA composites have no change. The results suggest that: sub-micron HA can be mixed well with PLLA by ultrasonic oscillation, which would improve the interface of sub-micron HA/PLLA composites.