Applications of microscopy to polymers

The increased use of optical and electron microscopy applied to polymer research has been the result of widespread acceptance of the techniques and extended property requirements of the polymer materials. It is known that the structures present in a polymer reflect the process variables, and further that they greatly influence the physical and mechanical properties. Thus, the properties of polymer materials are influenced by their chemical composition, process history and the resulting morphology. Morphological study involves two aspects prior to the study itself selection of instrumental techniques and development of specimen preparation methods. Structural observations must be correlated with the properties of the material in order to develop an understanding of the material. 

What then are the key specimen preparation methods for studying polymer materials by microscopy techniques This topic could be organized in one of two ways, that is by each specific microscopy technique or by each preparation method. The approach that has been chosen is to describe each specimen preparation type for all microscopies in order to minimize overlap and also to make it simpler to use for reference. Those preparation methods chosen for discussion are the typical ones found to be of major utility in the industrial laboratory. They cover the full range of study of the industrial scientist, that is everything from rapid failure analysis to process optimization studies and fundamental research. The fundamental studies must often be fitted into a limited time framework that requires good choices of methods and techniques on a wide range of materials. 

Key issues in any microscopy study are that the polymer process must be understood and the structure characterized, in order to develop structure-property relationships. Yet, there are many questions for even the experienced materials scientist. Where do you start characterization 

Key issues in any microscopy study are that the polymer process must be understood and the 

Introduction to Polymers (Chapman and Hall, London, 1981). 

Polymer Single Crystals (Interscience, New York, 1963). 

The polymers used in fibers are linear, so the molecules are a few nanometers across and several hundred nanometers long. In unoriented materials, the molecules are coiled and folded into loose isotropic spheres. When a fiber is oriented, by drawing for example, the molecular 

Natural and S5mthetic textile fibers were among the earliest materials studied by electron microscopy. Guthrie [2] and Stoves [3] described the techniques and applications of fiber microscopy to industrial practice. Somewhat later, evidence was provided for an oriented microfibrillar texture in polymer fibers [4]. X-ray diffraction suggested an arrangement of fine structures about 50 nm long and 5nm wide in semicrystaUine fibers [5, 6]. Peterlin [7, 8] observed the formation of fibrils and microfibrils by the deformation and transformation of spherulites using various microscopy techniques. 

Reviews of specimen preparation methods for fiber microscopy and instrumental tech- 

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