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  1. Exercise 5.2. Translate into English:

  2. 1. Длинные цепи молекул полимеров состоят из одинаковых небольших молекул мономеров.

  3. 2. Сополимеры состоят из двух и более мономеров.

  4. 3. Пластмассы можно получать в виде листов, тон­ких пленок, волокон или гранул.

  5. 4. Молекулы полимеров могут быть линейными, ветвящимися или с поперечными связями.

  6. 5. Малый вес пластмасс и хорошие электроизоля­ционные свойства позволяют использовать их в радио­электронике и электроприборах, а также вместо ме­таллов.

  7. 6. Молекулы термопластов имеют извитую форму и, поэтому, они гибкие и легко растяжимы.

  8. 7. Эластомеры имеют большое число поперечных связей между молекулами.

  9. Text в: «types of plastics»

  10. 1. Epoxy resin.

  11. Epoxy resin is a thermoset plastic containing epoxy groups. Epoxy resin hardens when it is mixed with solidifier and plasticizer. Plasticizers make a polymer more flexible.

  12. Epoxy resins have outstanding adhesion, toughness, and resistance to attack from chemicals. They form strong bonds and have excellent electrical insulation properties. Large, complex, void-free castings can be made from them. They are also used as adhesives, and in composites for boat building and sports equipment.

  13. 2. PVC (polyvinyl chloride)

  14. PVC (polyvinyl chloride) is a thermoplastic polymer made from vinyl chloride is a col­ourless solid with outstanding resistance to water, alcohols, and concentrated acids and alkalis. It is obtain­able as granules, solutions, lattices, and pastes. When compounded with plasticizers, it yields a flexible mate­rial more durable than rubber. It is widely used for ca­ble and wire insulation, in chemical plants, and in the manufacture of protective garments. Blow moulding of unplasticized PVC produces clear, tough bottles which do not affect the flavour of their contents. PVC is also used for production of tubes or pipes.

  15. 3. Polystyrene.

  16. Polystyrene is a thermoplastic produced by the polymerization of styrene. The electrical insulat­ing properties of polystyrene are outstandingly good and it is relatively unaffected by water. Typical applications include light fixtures, toys, bottles, lenses, capacitor dielectrics, medical syringes, and light-duty industrial components. Extruded sheets of polystyrene are widely used for packaging, envelope windows, and photographic film. Its resistance to impact can be improved by the addition of rubber modifiers. Polystyrene can be readily foamed; the resulting foamed polystyrene is used exten­sively for packaging.

  17. 4. Polythene (polyethene, polyethylene)

  18. Polythene (polyethene, polyethylene) is a plastic made from ethane. It is one of the most widely used important thermoplastic polymers. It was first developed by the polymerization of ethane at a pres­sure of 2,000 bar at 200°C. This produced low-density poly­thene (LDPE). A relatively high-density form (HDPE) was synthesized in the 1950s using a complex catalyst. Poly­thene is a white waxy solid with very low density, rea­sonable strength and toughness, but low stiffness. It is easily moulded and has a wide range of uses in contain­ers, packaging, pipes, coatings, and insulation.

  19. Vocabulary:

  1. adhesion — прилипание

  2. adhesive — клей

  3. bond — связи, узы

  4. insulation — изоляция

  5. casting — литье

  6. void — пустота

  7. solid — твердое тело, твердый

  8. acid — кислота

  9. alkali — щелочь

  10. to obtain — доставать, получать

  11. granule — гранула

  12. solution — раствор

  13. lattices — латексы

  14. paste — паста

  15. yield — выход

  16. durable — прочный

  17. rubber — резина, каучук

  18. garment — предметы одежды

  19. lens —линза

  20. capacitor — эл. конденсатор

  21. syringe — шприц

  22. light-duty — неответственный

  23. envelope — зд. обрамление

  24. impact — удар

  25. improved — улучшенный

  26. modifiers — модификаторы

  27. addition — добавление

  28. readily — легко, с готовностью

  29. foam — пена

  30. catalyst — катализатор

  31. wax — воск

  32. reasonable — приемлемый, неплохой

  33. coating — слой, покрытие