高性能刷状ZnO介晶的制备及其对复合树脂性能的增强作用

Preparation of High Performance Brush-Like Zinc Oxide Mesocrystals and Its Reinforcing Effect on Properties of Resin Composites

无机填料作为齿科复合树脂的主要成分,对其性能影响最为显著。本文以阿拉伯胶为结构导向剂,用热水解法合成了多孔、分级结构的刷状ZnO介晶,其厚度和直径分别为1.2μm和1.0μm。通过微流控制法在其表面包覆了4~6 nm无定形SiO_(2),以利于其表面硅烷化。通过场发射扫描电镜(FE-SEM)、X射线衍射仪(XRD)、热重分析仪(TGA)等对其进行了表征。对ZnO@SiO_(2)进行硅烷改性处理后,将其作为辅助填料,与改性纳米SiO_(2)主填料一起添加到Bis-GMA/TEGDMA树脂体系中,光固化得到齿科复合树脂。力学测试表明,ZnO@SiO_(2)填充质量分数控制在5%以内时可有效提高复合树脂力学性能。与单一二氧化硅填料的复合树脂相比,添加填充质量分数3%ZnO@SiO_(2),复合树脂的力学性能表现最佳,其弯曲强度、弯曲模量和压缩强度分别提高了12.9%、6.6%和3.7%,同时还表现出优良的抗菌活性,对变异链球菌抗菌率达98.7%。此外,添加了ZnO@SiO_(2)介晶填料的复合树脂还具备更好的耐磨性。

The inorganic filler is the main component of dental resin composite,which is very important for the properties of resin composite.In this paper,ZnO mesocrystals with porous and hierarchical structure were achieved by a thermal hydrolysis method using gum arabic as structure-directing agent.The thickness and diameter of the synthesized ZnO mesocrystals were about 1.2μm and 1.0μm.The amorphous silica in a thickness of 4~6 nm was uniformly coated on the surface of ZnO mesocrystals via the microfluidc process.ZnO mesocrystals were characterized by field-emission scanning electron microscopy(FE-SEM),X-ray diffraction(XRD)and thermogravimetric analysis(TGA).The ZnO@SiO_(2) was firstly modified with 3-methacryloxypropyl trimethoxysilane(γ-MPS),and mixed with modified SiO_(2) nanoparticles as co-filler.Subsequently modified inorganic particles were added into Bis-GMA/TEGDMA to prepare dental composite resin by light-curing.The mechanical testing show that the mass fraction of ZnO@SiO_(2)(≤5%)could improve the mechanical properties of composite resin effectively.The silica matrix composite resin filled with 3%ZnO@SiO_(2) demonstrates the best mechanical properties,among which the flexural strength,flexural modulus and compression strength increase by 12.9%,6.6%and 3.7%,respectively,in comparison with the composite using of only SiO_(2) filler.This optimal composite also exhibits superior antimicrobial activity,with antibacterial rate up to 98.7%to Streptococcus mutans.In addition,the composite resin with ZnO@SiO_(2) also has better wear resistance.