Department of Materials Science and Engineering, Jinan University, Guangzhou 510632, China.
First Affiliated Hospital, Jinan University, Guangzhou 510632, China.
J Mech Behav Biomed Mater. 2019 Feb;90:604-614. doi: 10.1016/j.jmbbm.2018.11.002. Epub 2018 Nov 19.
Polyhedral oligomeric silsesquioxane reinforced poly (L-lactic acid) nanocomposites (PLLA/POSS) were prepared to overcome the insufficient mechanical properties of PLLA. In order to improve the compatibility between the nanofillers and matrix, PLLA chains were grafted onto the POSS nanoparticles via microwave-assisted ring opening polymerization (ROP). Herein, a series of interface-modified polyhedral oligomeric silsesquioxane (POSS-(PLLA)) nanoparticles with various PLLA tail lengths were synthesized and the influence of the structure and additional amount of POSS nanoparticles on the properties of PLLA based nanocomposites were studied. POSS nanoparticles exhibit effective nucleation activity and lead to a significant improvement in the mechanical strength, thermal stability and biocompatibility of the resulting nanocomposites. The addition of 6 wt% POSS-(PLLA) 600 shows the optimal mechanical properties owing to has the longest PLLA tail length on POSS core, which possesses the optimal interfacial compatibility between POSS nanoparticles and PLLA. The Young's modulus improved by 57% and the tensile strength increased by 26.5% compared with neat PLLA. Moreover, the introduction of POSS nanoparticles lead to a porous fiber structure when processed by electrospinning and the nanofibrous scaffold effectively promoted cells adhesion and spreading. These results demonstrate the potential applications of the PLLA/POSS nanocomposites in tissue engineering and regenerative medicine.
多面体低聚倍半硅氧烷增强聚（L-乳酸）纳米复合材料（PLLA/POSS）被制备以克服 PLLA 的机械性能不足。为了提高纳米填料与基体之间的相容性，通过微波辅助开环聚合（ROP）将 PLLA 链接枝到 POSS 纳米粒子上。在此，通过微波辅助开环聚合（ROP）合成了一系列具有不同 PLLA 尾长的界面改性多面体低聚倍半硅氧烷（POSS-（PLLA））纳米粒子，并研究了 POSS 纳米粒子的结构和添加量对 PLLA 基纳米复合材料性能的影响。POSS 纳米粒子表现出有效的成核活性，导致所得纳米复合材料的机械强度、热稳定性和生物相容性得到显著提高。添加 6wt% POSS-（PLLA）600 表现出最佳的力学性能，因为 POSS 核上具有最长的 PLLA 尾长，具有 POSS 纳米粒子与 PLLA 之间最佳的界面相容性。与纯 PLLA 相比，杨氏模量提高了 57%，拉伸强度提高了 26.5%。此外，当通过静电纺丝处理时，POSS 纳米粒子的引入导致纤维呈现多孔结构，纳米纤维支架有效地促进了细胞的黏附和铺展。这些结果表明 PLLA/POSS 纳米复合材料在组织工程和再生医学中的潜在应用。
