聚乳酸/硅灰石生物医用复合材料的降解性能

Degradability of Poly(DL-lactide)/Wollastonite Composite as Biomaterial

对聚乳酸/硅灰石这种新型的生物医用复合材料进行了研究.采用溶剂共沉淀法制备含不同质量分数硅灰石(5%,10%,20%和30%)的复合物材料并模压成型,测定其力学性能,包括拉伸强度和弯曲强度.结果表明,在聚乳酸基体中加入硅灰石,其力学性能有所下降,仅当硅灰石质量分数为10%时,拉伸强度略高于纯聚乳酸材料.选取含硅灰石10%的复合材料放入37.5°C恒温模拟体液中浸泡1,2,4,6,8,11,14,17,20,24及28周,考察其体外降解性能,包括质量损失、体系pH值变化及力学强度的变化.在降解过程中,聚乳酸/硅灰石复合材料降解速度较慢,并且保持相对较好的力学性能,适于应用在骨修复及骨组织工程领域.

PDLLA/wollastonite composite is a new biomedical material. It is prepared through a solvent coprecipitation method with different content of wollastonite （5%, 10%, 20% and 30% ）. The samples are molded with pressure and their mechanical properties, including tensile Strength and bending strength are evaluated. The mechanical properties of the composition show that the influence of introduction of wol- lastonite and most composites have lower mechanical properties compared to pure PDLLA, except the PDL- LA/wollastonite composite with 10 wt% wollastonite, which has higher tensile strength. The in vitro degradability of the composites with 10% wollastonite in post-immersion in simulated body fluids （SBF） at 37.5℃ is systematically monitored at varying time periods of 1, 2, 4, 6, 8, 11, 14, 17, 20, 24 and 28 weeks. The measurements of weight loss, pH and the mechanical strength of the samples indicate that PDLLA/wollastonite composite degrades slower than the pure PDLLA does. And during the composite has higher mechanical strength than the pure PDLLA. that the DLLA/wollastonite composite is suitable for bone repair and Such properties in the degradation, degradation show bone tissue engineering.