新型改性的n-HA与PLGA复合材料的制备及性能研究

采用硅烷偶联剂(KH550)和L-丙交酯LLA联合接枝处理的新方法对纳米羟基磷灰石(n–HA)进行表面改性, 然后将其与聚乳酸-羟基乙酸(PLGA)作不同比例复合(n-HA为3wt%、10wt%、20wt%及30wt%), 得到改性n-HA/PLGA复合材料(g-n-HA/PLGA)。将其与未改性n-HA及未改性n-HA/PLGA复合材料作对比检测。结果表明, 该联合处理方法是n-HA进行表面接枝改性的新型有效方法。且改性处理后的n-HA与未改性处理的n-HA相比, 能更好地在PLGA基体中分散均匀, 并能提高PLGA结晶能力和PLGA的力学性能。当改性处理后的n-HA添加量为10wt%时, 其复合材料抗弯强度和拉伸强度分别比未改性n-HA/PLGA提高14.4%和11.3%。该新型g-n-HA/PLGA复合材料有望用作骨折固定材料。

Preparation and Characterization of Nano-hydroxyapatite/PLGA Composites with Novel Surface-modified Nano-hydroxyapatite

Nano-hydroxyapatite (n-HA) was modified by a new method of combining silane coupling reagent (KH550) with surface-grafting L-lactide LLA. Then, the surface-modified n-HA (g-n-HA) was introduced into poly(lactic-co-glycolic acid) (PLGA) to prepare a series of g-n-HA/PLGA composites with the concentration of 3wt%, 10wt%, 20wt% and 30wt%. The properties of the g-n-HA/PLGA composites were characterized and compared with PLGA and n-HA/PLGA composites. The results show that n-HA is successfully modified by KH550 and L-LA. The g-n-HA particles could disperse more uniformly in PLGA matrix and promote PLGA to crystallize. The obtained g-n-HA/PLGA composites has better mechanical properties than those of n-HA/PLGA composites with the same amount of n-HA. Moreover, the bending and tensile strength of g-n-HA/PLGA composite containing 10wt% g-n-HA are 14.4% and 11.3% which is higher than that of pure PLGA, respectively. Therefore, the g-n-HA/PLGA composite is promising for bone fracture internal fixation material in future.