Special Techniques and Applications

Historically, EM has played important role in elucidating the structure and properties of various processing forms of classical polymer blends, composites fibers and biomedical objects. The microscopic analysis of certain special types of blend are examined in the following subsections. 

RUO4 as staining agent (b) AFM phase image of the same biend. 

It should be noted, however, that several attempts were required to stain the PC phase sufficiently for TEM imaging, whereas the difference in bulk mechanical properties between PET and PC was sufficient to obtain a sharp contrast in the AFM images, within minutes of microscope operation. 

It should be noted that, whilst TEM and AFM may not be suited to the imaging of vesicular structures in drug-delivery systems, SEM may offer an excellent solution to the problem. In fact, environmental scanning electron microscopy (ESEM) provides an elegant approach to imaging the structures of biomedical materials at high resolution, and occasionally also under the physiological conditions encountered in body tissues [10]. 

During the past few decades, much prt ess has been made in the field of microscopic techniques based on spectroscopy. One such method is scanning transmission X-ray microscopy (STXM) which permits the nondestmctive chemical mapping of heterogeneous polymers (including polymer alloys) through different specimen 

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