Investigation of size-effect on mechanical properties of nanoscale polymers

该项目的目的是研究纳米级聚合物的机械性能及其尺寸依赖性。利用双光子纳米光刻技术制备了半径为100-500 nm的聚甲基丙烯酸甲酯纳米线螺旋弹簧。利用激光捕获和原子力显微镜悬臂梁两种方法测量了所制备的纳米螺旋弹簧在干燥条件下的弹簧常数。从弹簧常数以及纳米螺旋弹簧的几何参数出发，研究了聚合物的弹性模量。结果表明，随着PMMA聚合物丝直径的减小，聚合物的弹性模量增大。

The purpose of this project was to investigate mechanical properties of polymers in the nanoscale and their size dependence. Two-photon nanolithography was utilized to fabricate coil springs made of poly(methyl-methacrylate) nanowires with radii of 100-500 nm. Spring constants of the fabricated nano coil springs were measured in dried condition by utilizing two methods : laser trapping and atomic force microscope cantilever. From the spring constant, as well as the geometrical parameters of nano coil springs, the elastic modulus of polymer was investigated. The result shows that the elastic modulus of polymer increases with the decrease of the diameter of PMMA polymer wires.