纳米HA对PLA/PCL复合材料降解性能的影响

Effect of Nano-HA on the Degradation Properties of PLA/PCL Composites

以聚乳酸(PLA)为基体,添加聚己内酯(PCL)以及羟基磷灰石(HA)熔融共混得到PLA/PCL/HA复合材料,研究其力学性能与降解性能。结果表明,当材料配方为PLA80/PCL20/HA5时,复合材料的综合力学性能最好,断裂伸长率从5%提升至40%;通过差示扫描量热仪(DSC)测试了复合材料的结晶性能,HA的加入起到异位成核点的作用,结晶度从2.6%提升至8.9%,玻璃化转变温度从60.13℃降至56.84℃,扫描电镜(SEM)观察了复合材料的界面相容度,发现HA的加入提升了PLA与PCL的相容度;通过水解降解过程中的pH值测试与三维超景深显微镜观察得知,由于HA在水解过程中溶解脱落,使得复合材料整体被破坏,水解速率快于纯聚乳酸。

Poly(lactic acid)(PLA)/polycaprolactone(PCL)/hydroxyapatite(HA)composites were obtained by melt-blending PLA with PCL and HA as the matrix,and their mechanical and degradation properties were investigated.The results show when the material ratio is PLA80/PCL20/HA5,the comprehensive mechanical properties of the composites are the best,and the elongation at break increases from 5%to 40%.The crystallization properties of the composites are tested by differential scanning calorimetry(DSC).The addition of HA acts as an ectopic nucleation site,the crystallinity increases from 2.6%to 8.9%,and the glass transition temperature decreases from 60.13 ℃ to 56.84 ℃.Scanning electron microscopy(SEM)observes the interfacial compatibility of the composites and finds that the addition of HA enhanced the compatibility of PLA with PCL.Through the pH test and three-dimensional super depth of field microscope observation during the hydrolysis degradation process,it is found that the composite material is destroyed due to the dissolution and shedding of HA during the hydrolysis process,and the hydrolysis rate is faster than that of pure polylactic acid.