Microscopy of polymers

Microscopy is the name given to a group of experimental methods which permit magnification of morphological structures to make details visible. 

The morphology of polymer blends, block copolymers, semicrystalline polymers and liquid-crystalline polymers can be assessed by microscopy. The morphology can be directly observed and the structure is in most cases assessed without the need for any sophisticated model. Small-angle X-ray 

What must be questioned is whether the image obtained by microscopy is free from distortions and artefacts. It is quite possible that the dimensions of the structural features will be affected by the radiation. Radiation effects are very rare in optical microscopy but they are common in electron microscopy. Some polymers show a great sensitivity to the electron beam and rapidly degrade, leaving a hole in the specimen. More moderate damage, e.g. shrinkage of the specimen, may also occur. 

The purpose of the sample preparation is to obtain a contrast-rich representation of the True structure. If contrast is not naturally present in the specimen, it may be created by staining, i.e. adding a substance with a characteristic colour or high (electron) density selectively to a specific phase. The contrast may also be achieved by selective etching, leaving a topography indicative of the phase structure. It is possible, however, that the preparation method used may produce artificial structures. 

A third problem originates from the fact that only a small part of the whole object is studied. Is that part representative of the object The amount of information obtained from the observations is substantial and the microscopist has to select only a few features which are typical of the specimen. It is, however, a clear possibility that non-typical features are presented. 

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Ribbe A E 1997 Laser scanning confocal microscopy in polymer science Trends Polym. Sc/. 5 333-7 Oliveira M J and Hemsiey D A 1996 Optical microscopy of polymers Sonderb. Prakt. Metallogr. 27 13-22 Nie Sh and Zare R N 1997 Optical detection of single molecules Ann. Rev. Biophys. Biomol. Struct. 26 567-96 Masters B R 1994 Confocal redox imaging of cells Adv. Mol. Cell Biol. 8 1-19... 

Bhawalkar J D, Swiatkiewicz J, Pan S J, Samarabandu J K, Liou W S, He G S, Berezney R, Cheng P C and Prasad P N 1996 Three-dimensional laser scanning two-photon fluorescence confocal microscopy of polymer materials using a new, efficient upconverting fluorophore Scanning 18 562-6... 

Ling X, Pritzker M D, Byerley J J and Burns C M 1998 Confocal scanning laser microscopy of polymer coatings J. Appl. Polym. Sc/. 67 149-58... 

Snetivy D and Vancso G J 1994 Atomic force microscopy of polymer crystals 7. Chain packing, disorder and imaging of methyl groups in oriented isotactic polypropylene Po/yme/ 35 461... 

Ratner, B. and Tsukruk, V., Eds., Scanning Probe Microscopy of Polymers, ASC Symposium Series 694, Washington DC, 1998. 

Chemoff, D. and Magonov, S., Atomic Force Microscopy of Polymer Characterization and Analysis, in Comprehensive Desk Reference, Brady, Jr., R.F., Ed., ACS, Oxford University Press, Oxford, United Kingdom, 2003, chap. 19. 

There are two types of stages for dynamic microscopy (a) hot and cold stages and (b) tensile stages [1], Hot stages are most commonly used for the dynamic microscopy of polymers [1,43]. Thermal analysis in the OM is complementary to other thermal analysis methods, such as differential thermal analysis (DTA) [1], Direct observation of the structural changes of a polymer as a function of temperature can determine the nature of phase changes and thermal decomposition [1], It also measures the transformation temperatures. 

Fagan, A. F., Bell, J. M., and Briggs, G. A. D. (1989). Acoustic microscopy of polymers and polymer composites. In Fractography and failure mechanisms of polymers and composites (ed. A. C. Roulin-Moloney), pp. 213-30. Elsevier Applied Science, London. [204]... 

This review article describes progress made in scanning force microscopy of polymers during the last 5 years including fundamental principles of SFM and recent developments in instrumentation relevant to polymer systems. It focuses on the analytical capabilities of SFM techniques in areas of research where they give the most unique and valuable information not accessible by other methods. These include (i) quantitative characterisation of material properties and structure manipulation on the nanometer scale, and (ii) visualisation and probing of single macromolecules. 

Ratner BD, Tsukruk VV (eds) (1998) Scanning probe microscopy of polymers. ACS Symposium Series 694. American Chemical Society, Washington DC... 

Figure 5.17 Topography of crystalline polyethylene. The chain folds of the crystal structure generate the rough appearance. (Reproduced with permission from B.D. Ratner and V.V. Tsukruk (eds), Scanning Probe Microscopy of Polymers, American Chemical Society, Washington D.C. 1998 American Chemical Society.)...

Schdnherr, H., Vancso, G. J. Scanning Force Microscopy of Polymers ISBN 3-642-01230-3... 

The book by Sawyer and (irubb" provides a more detailed account of electron microscopy of polymers and in particular, an excellent overview of the different sample preparation techniques that have been devised. 

Scanning Electron Microscopy of Polymers and Coatings" Princen, L. H., Ed. J. Wiley-Interscience New York, 1971,... 

Michler GH. Electron Microscopy of Polymers. Springer-Verlag Berlin Germany 2008. 

D.C. Coffey and D.S. Ginger, Time-resolved electrostatic force microscopy of polymer solar cells. Nat. Mat., S, 735 (2006). 

Polymer Microscopy by L. C. Sawyer and D. T. Grubb, 2nd Edn, Chapman and Hall, London, 1996. This book covers all aspects of the electron and optical microscopy of polymers, with many examples of its application. 

K. B. Burke, A. J. Stapleton, B. Vaughan, X. Zhou, A. L. D. Kilcoyne, W. J. Belcher, P. C. Dastoor, Scanning Transmission X-Ray Microscopy of Polymer Nanoparticles Probing Morphology on Sub-10 Nm Length Scales. Nanotechnology 2011,22,265710. 

Burke, K.B., Stapleton, A.J., Vaughan, B Zhou, X., Kilcoyne, A.L.D., Belcher, W.J., and Dastoor, P.C. (2011) Scanning transmission X-ray microscopy of polymer nanoparticles probing morphology on sub-lOnm length scales. Nanotechnology, 22, 265710. 

Georg, H., Michler. (2008). Electron microscopy of polymers. Springer. 

M.R. Libera, R.E. Egerton, Advances in the transmission electron microscopy of polymers, Polymer Reviews 50 (2010) 321-339. 

Drummy, Lawrence, F., Yang, Junyan and Martin, David C. (2004). Low-voltage electron microscopy of polymer and organic molecular thin films. Ultramicroscopy, 99(4) 247-256. doi 10.1016/j.ultramic.2004.01.011. PMID 15149719. 

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