Polymer blends, functional groups enhance

Staining permits TEM observation of the dispersed phases in multiphase blends. Osmium tetroxide is the most commonly used stain for this application, while other stains have more limited application. Detailed fine structure of polymers is also made visible by staining. For example, chlorosulfonic acid staining enhances the lamellar texture of PE [105]. There are cases where a stain has been associated with a specific functional group of polymers. A specific stain for nylon, developed by Reimschuessel and Prevor-sek [106], showed the sizes of the macrofibrils and microfibrils of nylon. Fibers were immersed in 10% aqueous solution of SnCl2 for 10 min at 100°C, rinsed, placed in NH4OH solution to convert the tin chloride to insoluble SnO and then embedded for ultrathin sectioning. 

Several research groups [90, 91] have shown that the choice of the polymer matrix can significantly influence the location of the conductive filler in polymer blends due to the different interactions between these polymers and the filler. Conductive nanofiUers are often located in the polymer phase that has good affinity with them. Fu et al. [92] showed that the functionalization of filler can also change the distribution of the filler in polymer blends. Moreover, Potschke et al. [89] used a reactive component to tune the interaction between SAN and CNTs in a polymer blend based on PC and SAN. It is observed that CNTs transferred from the PC phase to the SAN phase after the addition of the reactive component due to an enhanced interaction. 

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