Effect Of Stirring On Interfacial Assembly Of Polymers And Nanowires

Interfacial assembly is a common method used to prepare thin films. It is the process that assembling primitives including metals and polymers are adsorbed onto the fluid interfaces, then form layered films. Stirring is the commonly used method to transfer substance and heat in experimental research and process of production. At the same time, stirring also can produce certain driving force, so it is widely used in polymer body-assembly. But the influence of stirring on the study of interfacial assembly is less. This paper has carried out the following two aspects.Firstly, we studied stirring effects on interface assembly of the polymer multilayer films. AFM, UV-Vis and XRR were used to track growth and detect morphology of polymer films. On one hand, we found out that roughness of films prepared under stirring was as good as films under still, but growth rate of films was higher than films under still. On the other hand, experimental results showed that the assembly speed would rise because stirring could increase contact probability between polymer and substrate in deposition stage, and roughness could reduce because stirring could wash away polymer adsorbed physically in rinsing stage.Secondly, we studied the stirring effects on interface assembly of nanowires. High length to diameter ratio of Te nanowires were synthesized and then used to assembly films. SEM images showed that Te nanowires can be orderly assembly under stirring. Solution viscosity, the base position and stirring speed could significantly influence the order of Te nanowires. And assembly density of nanowires could be controlled by solution concentration. In addition, the practical application of orderly Te nanowires was studied. They were transformed into Pt/Pd/Ag2Te nanowires by chemical reaction. SEM and EDS showed that almost all of the Te nanowires were changed into expected nanowires, and these nanowires were also ordered.