Surface properties polymer solid, variation

Surface chemical composition is an important property of a membrane and it can be markedly different from the bulk composition. ESCA is a technique which can generally probe the top 5 nm of a solid, and variations in the surface chemical composition with depth can be obtained by systematic changes in the photoelectron takeoff angle. The angle-resolved ESCA technique results in enhanced surface analysis . Studies of polymer surfaces with ESCA are abundant in the literature but the analysis of desalination membranes with ESCA has not yet been reported. 

One of the major requirements related to combinatorial material research is, however, the preparation of thin films and dots from solution in a fast and reproducible manner. Furthermore, the parallel investigation of the physical properties of these films is required to develop a more detailed understanding and new structure-property relationships. Ink-jet printing can bridge the gap between polymer synthesis and solid-state or surface property evaluation, since the technique opens the way to the automatic preparation of libraries of polymers, polymer blends, and composites, with a systematic variation of parameters such as chemical composition or thickness." ... 

An important difference between solution-phase and solid-phase chemistry is the new variable the polymer support. The polymer has significant influence on the reaction. There have been many solid supports used over the years with variation in polymer type, degree of cross-linking, and even quality. These factors have significant influence on solvation properties and reaction kinetics, and hence on synthesis characteristics. Various grafted polymers may have characteristics that differ from other supports. Consequently, the optimal conditions for a reaction on one polymer may be different from those for the same reaction on a different polymer. This should not dishearten the chemist. A reported reaction may be used as the basis for optimization studies of the reaction on a different support. Variables such as solvent, temperature, and reaction time may all be investigated to optimize the reaction on the new surface. 

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