Exercise 4. Fill in the blanks using terms given below:

Insulating polymers are a category of … materials widely used in electrical apparatus, exhibiting low … concentration and mobility, thus low electrical … , even at high fields. Carriers in insulating polymers are introduced by … and … , as well as by charges injected from the electrode-insulation … . When the electrical field applied to the polymer is higher than the threshold for … accumulation, charge would be … into the bulk material from the interface of polymer-electrode and … , forming homocharge or … . Based on this traditional conduction mechanism, the … is a continuous flow of carriers, which gradually approaches a steady state … at a given time after the onset of voltage application. Recently, a brand new phenomenon of … was discovered in some insulating polymers (e.g., minicable with polyethylene insulation and nanostructured epoxy-based material) at relatively low … , through the use of an ultra fast space charge acquisition system and a conduction current … apparatus endowed of low-pass filter. Charge pulses (packets) are observed to travel very rapidly through the insulation bulk with mobility 4 to 5 orders of magnitude higher than that for conventional conduction.

Terms: charge carrier, contaminants, interface, injected, heterocharge, current, value, electrical fields, measurement, conductivity, accumulate, space charge, impurities, organic, , charge transport.

Exercise 5. Find in the text constructions noun + noun + noun… and translate them .

Exercise 6. Look through the text and give a short summary of it.

Conducting Polymer Nanostructures

With the advancement of science and technology the world around us is shrinking and the importance of nanostructures is increasing. Attaining the nanoscale control over the spatial arrangement of the building blocks of materials has become an important objective of material scientists, because organization of materials on nanoscale very often leads to materials with physical properties distinctly different from the bulk counterpart. A new branch of science has been established for studying the preparation, properties, and application of such smaller objects of different size, shape, and origin. In view of this recently emerging field of nanoscience and nanotechnology, a nanomaterial is defined as one consisting of a substance or structure, at least one of the dimensions of which is less than 100 nm (0.1 _m). It has been repeatedly established that materials with such reduced dimension are especially important for showing fascinating electronic, optical, and magnetic properties. Science and technology of such micro- and nano-sized materials and objects are studied under different titles viz. micro- and nano-electronics, microelectromechanical systems (MEMS), micromolding in capillaries (MIMIC), etc. . In parallel with the progress of nanotechnology, importance of multifunctional and lightweight materials, suitable for fabrication of smaller devices, is also increasing. Inherently conducting polymers (ICP) top the list of the smart and intelligent materials that can be successfully utilized for fabrication of different optical devices (LED and ECD), rectifying diodes, transistors, photovoltaic cells, rechargeable batteries, sensors for chemical and biochemical species, and so on. However, some inherent difficulties in the nature of conducting polymers, such as their insolubility and infusibility, brittleness, poor mechanical property, etc. have primarily obstructed their successful and widespread application. For the same reason, to get conducting polymer based nanomaterials in hand was not as easy as other polymers, at least up to the first 15 years after their discovery.