Thin films polymer blend

In a large part of what we have discussed above, we considered binary polymer mixtures. However, the situation is somewhat different, if instead of polymer blends, thin films of block copolymers are investigated. Due to the molecular connectivity of the different blocks, the inherent length scale is now determined by the size of the molecules. Early experiments focussed on the thin film morphology in symmetric diblock copolymers, where surface interactions tend to orient the block copolymer lamellae parallel to the boundary surfaces. In contrast to most bulk specimens, the planar interfaces lead to the formation... 

Babel, A., Wind, J.D. and Jenekhe, S.A., Ambipolar charge transport in air-stable polymer blend thin-film transistors, Adv. Func. Mater, 14, 891-898, 2004. 

Sharma, S. Zhang, W. Schrag, E. Hsaio, B. Mather, P. T. Sokolov, J. Rafailovich, M. H. Gersappe, D. Luo, H., Polymer Blend Thin Films with POSS Compatibilization and Dewetting. Chicago Am. Chem. Soc. Meeting 2001. 

In order to obtain more accurate spatial information on the polymer blend surface, a highly focused probe SIMS, namely NanoSIMS, can be used. Indeed, the lateral resolution (in the range of some tens of nanometers) of this technique would be expected to be sufficient for imaging the domains [8,9]. Due to dynamic SIMS conditions of the measurement, and to the limited thickness of the polymer blend thin films, it is possible to acquire only a few frames before reaching the substrate [10], NanoSIMS has been used with some success to study the surface morphology and composition of thin-film polymer systems [8-lOj. 

Polymer blend thin films are interesting both for their technological applications (e.g., coatings) and from an academic point of view. By confining a polymer (blend) in a thin film, both the air-polymer and the polymer-substrate interface can (significantly) influence its physical properties, in comparison with those observed in bulk [12]. 

Polymer blend thin films are interesting both for their technological applications (e.g., coatings), and from an academic point of view [12]. 

At this point, a number of the critical and experimental issues associated with ToF-SIMS imaging will be discussed, and several recent applications of ToF-SIMS imaging to the study of polymer blend thin films [137] reviewed. 

Li X, Han Y, An L. Surface morphology control of immiscible polymer-blend thin films. Polymer 2003 44 8155-8165. 

In the last decade, there has been great interest in the imdeistanding of the phase-separation process in the production of the thin films of immiscible polymer blends. This curiosity is as a direct consequence of the particular surface structures found in polymer blends that will define their final surface properties. Due to the extensive literature concerning both theoretical [9,17-21], and experimental [22] studies this part will be limited in order to briefly present the main concepts on polymer blends thin films. 

DalnokiVeress K, Forrest JA, Stevens JR, Dutcher JR. Phase separation morphology of spin-coated polymer blend thin films. Physica A 1997 239 87-94. 

Zhang Newby B-M, Wakabayashi K, Composto RJ. Confinement induced stabilization in polymer blend thin films. Polymer 2001 42 9155-62. 

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