Ultraviolet spectroscopy, polymer properties

Emulsion polymers and commercial controls were milled (Table III) and molded (Table IV) to produce test samples, and properties were evaluated following standard ASTM procedures (Tables V-VII). During accelerated ultraviolet light aging, the polymers were also examined by infrared spectroscopy of films cast from o-dichlorobenzene solution (Table VIII). 

These devices are based on the anisotropic absorption of light. Usually molecular crystals exhibit this property and tourmaline is the classical example for this. For practical purposes, however, micro crystals are oriented in polymer sheets. Polymers containing chromophors become after stretching dichroic polarizers. The devices produced in this manner are called polawids. They have found a broad application in many technologies. Their application in spectroscopy is limited to the near ultraviolet and to the visible and near infrared range of the spectrum. In vibrational spectroscopy polaroids are employed as analyzers only for Raman spectroscopy. 

In order to gain information on the elecronic structure of polymer sulfur nitride, (SN)X, we investigated the photoemission properties of this interesting material. The measurements were obtained on nonoriented (SN)X films using x-ray and variable ultraviolet photoemission spectroscopy (XPS and UPS) (1), (2). Table 1 shows the nitrogen and sulfur core levels in (SN)X and in neutral elements. 

This chapter describes fundamental aspects of the electronic structure of organic semiconductors (small molecules and polymers), and their interfaces, and the method to bridge the electronic structure and electrical property more directly using ultraviolet photoemission spectroscopy (UPS). Penning ionization electron spectroscopy (PIES), which is the most surface-sensitive method, is also introduced for study of electronic states at outermost surfaces of solids, which are responsible for charge exchange through the interfaces between different materials when they get contact to form a hybrid system. 

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