Multicomponent morphological characterization

As more complex multicomponent blends are being developed for commercial appHcations, new approaches are needed for morphology characterization. Often, the use of RuO staining is effective, as it is sensitive to small variations in the chemical composition of the component polymers. For instance PS, PC, and styrene—ethylene/butylene—styrene block copolymers (SEES) are readily stained, SAN is stained to a lesser degree, and PET and nylons are not stained (158,225—228). 

Patel N (1990) Multicomponent network and linear polymer system Thermal and morphological characterization. PhD dissertation, URL + S.U. (under MacGrath JE)... 

A powerful method of examining the morphology of many multicomponent polymer materials utilizes transmission electron microscopy [Woodward, 1989]. If the two phases are nearly equal in electron density, staining with osmium tetroxide or other agents can be used. For more detailed discussion on the methods of morphology characterization, see Chapter 8. 

The high contrast afforded by intermittent contact imaging for multicomponent polymer blends has enabled AFM to become a leading tool for morphology characterization, complementing TEM in many cases, but without the requirement of staining [141,144-146]. 

We come now to one of the principal difficulties in the field of aerosol measurements, namely, the determination of chemical composition. The difficulties stem from a number of factors. Aerosols formed under uncontrolled circumstances such as many industrial emissions or the ambient aerosol are often multicomponent. Compo.sitlons differ significantly from particle to particle an individual particle may be a highly concentrated solution droplet containing insoluble matter such as chains of soot particles. The size composition probability density function (Chapter I) can be used to characterize the chemicals and size properties of such systems (but not their morphology). 

The structure and morphology of the membrane also influence its permeability. XRD has been widely applied for the characterization of crystalline structure, especially for confirmation of alloy formation in multicomponent materials and identification of bulk corrosion products. SEM and atomic force microscopy are routinely applied to the characterization of membrane topography and are helpful for identification of failure mechanisms. More advanced methods, including... 

---