倍半硅氧烷季铵盐型硅橡胶的可控制备及抗菌机理研究

Investigation about silicone rubber with antibacterial function have much scientific signification and good application prospect in the field of biomedical materials。In the present investigation, quaternary ammonium functionalized epoxy polyhedral oligomeric silsequioxane with controllable molecular structure are synthesized using γ-(2,3-epoxypropoxy) propytrimethosysilane by a sequential reactions including hydrolysis,epoxy ring opening addition and quaternization. Silicone rubbers with antibacterial activities are prepared by UV induced polymerization of quaternary ammonium functionalized polyhedral oligomeric silsequioxane and siloxane oligomer and crosslinker in the presence of cationic photoinitiator. The microstructure and properties of the anti-bacterial silicone rubbers including thermal stability, mechanical properties, antibacterial properties affected by the content and molecular structure of quaternary ammonium functionalized polyhedral oligomeric silsequioxane as well as preparation process are investigated. Reinforced mechanism of the silicone rubbers is explored. The influence factor and interaction between bacteria and silicone surface are investigated and antibacterial mechanism of the silicone rubbers is explored. Antibacterial endurance of the silicone rubber is evaluated and analysized.Varieties of content and distribution of antibicaterial groups on the surface of silicone rubber are investigated during the long time antibacterial process. Long acting antibiotic mechanism of silicone rubber materials is particularly explored. Vivo biocompatibility of the antibacterial silicone rubber is preliminary valued. The project will provide a basis for the development of antibacterial silicone rubbers with the biomedical applications.

研究具有抗菌功能的硅橡胶材料在生物医学材料领域具有一定的科学意义和良好的应用前景。本课题以γ-(2,3-环氧丙氧)丙基三甲氧基硅烷为原料经过水解，环氧开环加成，季铵盐化反应合成分子结构可控带有环氧活性基团的倍半硅氧烷季铵盐，将倍半硅氧烷季铵盐与硅氧烷低聚物和交联剂、阳离子光引发剂混合组成光固化体系，研究制备倍半硅氧烷季铵盐型硅橡胶抗菌材料。分析倍半硅氧烷季铵盐分子结构和含量以及制备工艺对硅橡胶材料微观结构、热稳定性、力学性能和抗菌性能的影响。探索倍半硅氧烷季铵盐对硅橡胶材料的增强机理，研究细菌与硅橡胶材料表面的相互作用机制以及影响因素，探索倍半硅氧烷季铵盐型硅橡胶抗菌机理。评价并分析硅橡胶材料的抗菌持久性，研究材料长期抗菌过程中表面抗菌基团含量和分布变化规律，探索硅橡胶材料长效抗菌机制。评价硅橡胶材料的体外生物相容性。课题研究为硅橡胶抗菌材料在生物医学领域的应用奠定良好的理论和技术基础。

具有抗菌功能的硅橡胶复合材料有望在医疗领域得到应用，本项目通过分子结构设计，以γ- 缩水甘油醚氧丙基倍半硅氧烷为基本原料，与N，N- 二甲基胺发生加成反应合成带季铵盐基团的倍半硅氧烷。结果表明：随着N，N- 二甲基胺碳链长度增大，季铵盐型倍半硅氧烷结晶温度升高，热稳定性先下降后升高；随着胺基与环氧基团摩尔比例增大，季铵盐型倍半硅氧烷结晶温度升高，热稳定性升高。季铵盐型倍半硅氧烷对大肠杆菌、金黄色葡萄球菌、白色念珠菌、痢疾菌、粪肠菌5种细菌都有显著的抗菌效果，并且随着季铵盐基团含量的增大抑菌圈直径增大。.以含氢硅油为基本原料，通过二步加成反应合成带季铵盐基团的硅油。结果表明：随着N’N-二甲基胺碳链长度增大，季铵盐型硅油结晶温度变化不明显，熔融温度升高，热分解温度下降，随着胺基与环氧基团摩尔比例增大，季铵盐型硅油结晶温度下降，热分解温度下降。季铵盐型硅油抗菌性随碳链长度的增大而降低，抗菌性以胺基与环氧基团摩尔比例0.8：1最优。.以γ-缩水甘油醚氧丙基倍半硅氧烷和甲基丙烯酸缩水甘油酯以及阳离子光引发剂复合组成固化体系，紫外光照固化获得复合材料。结果表明：复合材料硬度随γ-缩水甘油醚氧丙基倍半硅氧烷含量增大而增大，表面疏水性随γ-缩水甘油醚氧丙基倍半硅氧烷含量增大而增大，XPS结果表明随着γ-缩水甘油醚氧丙基倍半硅氧烷含量增大，材料表面C元素含量降低，O元素含量降低，Si元素含量增大。.以合成的季铵盐型倍半硅氧烷和甲基丙烯酸缩水甘油酯以及阳离子光引发剂复合组成固化体系，紫外光照固化获得季铵盐型倍半硅氧烷/甲基丙烯酸缩水甘油酯复合材料。结果表明：复合材料表面亲水性随季铵盐型倍半硅氧烷含量增大而增大，随季铵盐型倍半硅氧烷分子结构中季铵盐基团的比例增大而增大，季铵盐基团上的碳链长度对复合材料的亲水性影响不明显。XPS分析结果表明季铵盐型倍半硅氧烷含量，季铵盐基团的比例以及季铵盐基团中碳链长度对材料表面元素含量影响显著。