可生物降解纳米羟基磷灰石/聚酯型弹性体复合材料的制备及性能

Preparation and investigation of a biodegradable nano-hydroxyapatite/polyester elastomer composites

通过熔融缩聚法制备了纳米羟基磷灰石(n-HA)/聚1,2-丙二醇-癸二酸-柠檬酸酯(1,2-PP-SC)生物弹性体复合材料。用红外光谱(FTIR)和固体核磁共振光谱(13C NMR)对复合材料的化学结构进行表征,用扫描电子显微镜(SEM)和透射电镜(TEM)对n-HA的形态及其在基体中的分散性进行表征。结果表明,n-HA与癸二酸没有发生化学反应,n-HA与1,2-PPSC基体无明显化学键生成,n-HA均匀分散在1,2-PPSC基体中。动态力学性能(DMA)的测试结果表明,n-HA与1,2-PPSC基体之间生成了良好的界面结合。差示扫描量热(DSC)分析和DMA的测试结果表明,n-HA/1,2-PPSC复合材料玻璃化转变温度(Tg)随着n-HA质量分数的增加而降低,这是由于n-HA影响了聚合物酯化反应的进行,导致化学交联密度降低。n-HA的加入提高了复合材料的亲水性,降低了复合材料的吸水率,减缓了复合材料的降解速率。复合材料的力学性能与基体相比有明显的提高,当n-HA质量分数为20%时,复合材料的弹性模量提高11.4倍,拉伸强度提高8.2倍,且断裂伸长率基本不变。

Nano-hydroxyapatite（n-HA）/poly（（1,2-propanediol-sebacate）-citrate）（1,2-PPSC） composites were synthesized by condensation of 1,2-propanediol,sebacic acid,citric acid and n-HA.The structure was characterized by FTIR and 13C NMR;the micromorphology of n-HA and the dispersion property of n-HA in n-HA/1,2-PPSC composites were characterized by SEM and TEM.The results show that the chemical reactions between n-HA and sebacic acid never occur,n-HA and 1,2-PPSC matrix do not generate obviously chemical bond,and n-HA disperses uniformly in 1,2-PPSC matrix.DMA shows that there is a good interfacial bonding between n-HA and 1,2-PPSC matrix.DSC and DMA show that n-HA decreases the chemical cross-link density of the composites,so the Tg of the composites decreases with increasing of mass fractions of n-HA.N-HA improves the hydrophilicity,decreases water absorption and reduces the degradation rates of n-HA/1,2-PPSC composites.Compared to the matrix,the mechanical properties of the composites are improved obviously;when the mass fraction of n-HA is 20%,the modulus of n-HA/1,2-PPSC composites increases 11.4 times,the tensile strength of n-HA/1,2-PPSC composites increases 8.2 times,while the elongation at break of n-HA/1,2-PPSC composites is basically unchanged.