Benetzungsverhalten von phasensegregierten Blockcopolymeren

点击翻译按钮获取中文摘要

In the project applied we would like to investigate block copolymers and their blends with the corresponding homopolymers. By different degrees of demixing in the bulk, we want to tune the size of laterally demixed structures (i.e. the size of hydrophobic domains) on the top surface of thin films, prepared by special methods. Thus, the size of laterally demixing will be controlled from nanometer range (block copolymers) up to micros (blends). The variation of surface properties will be controlled by variation of the chemical composition of the block copolymers and blends as well as thermal treatment. For control and quantification of the molecular (chemical) and lateral (hydrophobic domains) structure and surface topography. XPS and AFM investigations will be used.The macroscopic wetting behavior will be investigated by contact angle measurements. The difference between macroscopic advancing and receding contact angles, i.e., the contact angle hysteresis, will be measured. The influence of molecular and surface structure (size and distribution of chemical heterogeneities) will be studied systematically. Beside variation of substrate characteristic, a variation of model liquids to be used for contact angle measurements will be carried out in order to detect contact angle hysteresis data in detail. Because of the extremly low surface energy of the systems studied and their chemical inertness, the nature of probe liquids (surface tension and polarity) can be varied in a very broad range. The project will help to establish correlations between molecular parameters and surface structure, which are not known for the system under investigation. The data obtained will be compared to predictions of theoretical models.