介孔纳米羟基磷灰石/左旋聚乳酸复合材料的制备及性能
Preparation and properties of mesoporous nano hydroxyapatite/poly (L-lactide) composites

为考察介孔纳米羟基磷灰石(MHA)/左旋聚乳酸(PLLA)复合材料的性能, 以十六烷基三甲基溴化铵(CTAB)为模板合成MHA, 采用溶液相分离结合粒子沥滤法制备了不同纳米粒子含量的MHA/PLLA多孔支架复合材料, 考察了其抗压缩性能和淬断面微观结构.采用溶液浇注法制备了MHA/PLLA复合膜, 并对其拉伸性能和拉伸断面微观结构进行了研究.FTIR、XRD、TEM和氮气吸附测试等结果显示:合成的MHA具有典型的晶体结构、介孔结构和较高的比表面积.力学测试结果显示:在发生10%压缩形变时, 填料含量为1%、5%和10%的MHA/PLLA多孔支架复合材料的抗压缩强度随填料含量增加而提高, 与相应含量的纳米羟基磷灰石(HA)/PLLA多孔支架复合材料相比, 分别提高了约37.0%、67.7%和144.7%.在填料含量为5%和10%时, MHA/PLLA复合膜的拉伸强度较HA/PLLA复合膜分别提高约38.7%和46.1%, 拉伸模量分别提高约35.4%和14.5%.而且MHA/PLLA复合膜具有更高的断裂伸长率, 填料含量为1%、5%和10%时断裂伸长率分别较HA/PLLA复合膜提高约91.3%、79.7%和96.1%.FESEM结果显示:尤其当填料含量较高时, MHA/PLLA多孔支架复合材料或复合膜中填料粒子分布较HA/PLLA中均匀.结果表明:与HA/PLLA复合材料相比, 随着MHA含量增加, MHA/PLLA复合材料具有更好的力学性能, MHA在PLLA基体中分布相对更均匀. To evaluate the properties of mesoporous nano hydroxyapatite (MHA)/poly(L-lactide) (PLLA) composites, MHA was synthesized with cetyltrimethylammonium bromide (CTAB) as template. MHA/PLLA porous scaffold composites with different contents of nano particles were prepared using solution phase separation and particle-leaching method, and the compressive property and micro-structure of quenching fracture cross-sections were evaluated. And then MHA/PLLA composite films were prepared using solvent casting method and the tensile property and micro-structure of tensile fracture cross-sections were evaluated. FTIR, XRD, TEM and N2 adsorption test results show that the prepared MHA has typical crystal structure, mesoporous structure and higher specific surface area. The mechanical test show that the MHA/PLLA porous scaffold composites with filler content of 1%, 5% and 10% exhibit increasing compressive strength under 10% compression deformation with the filler content increasing, and are 37.0%、67.7% and 144.7% higher than those of corresponding content of nano hydroxyapatite (HA)/PLLA porous scaffold composites, respectively. With the filler content of 5% and 10%, the tensile strength of MHA/PLLA composite films are 38.7% and 46.1% higher than those of HA/PLLA composite films, the strength modulus are 35.4% and 14.5% higher, respectively. And MHA/PLLA composite films possess higher elongation at break. With the filler content of 1%, 5% and 10%, the elongation at break are 91.3%, 79.7% and 96.1% higher than those of HA/PLLA composite films, respectively. FESEM photographs show that the distribution of filler particles in MHA/PLLA porous scaffold composites or composite films is more uniform than that in HA/PLLA when the filler content is higher. The results indicate that, compared with HA/PLLA composites, better mechanical property and more evenly MHA distribution in PLLA matrix are obtained as the increasing content of MHA.