What are Polymers? (Что такое полимеры?)

A key feature that distinguishes polymers from other molecules is the repetition of many identical, similar, or complementary molecular subunits in these chains. These subunits, the monomers, are small molecules of low-to-moderate molecular mass, and are linked to each other during a chemical reaction called polymerization. Although most polymers are organic, with carbon-based monomers, there are also inorganic polymers; for example, the silicones, with a backbone of alternating silicon and oxygen atoms.

7. Переведите отрывок на слух по предложению.

A polymer is a large molecule constructed from many smaller structural units called monomers joined together by covalent bonds. Polymers have existed in natural form since life began and those such as DNA, RNA, proteins and polysaccharides are some of the most important macromolecules found in plant and animal life. From the earliest times, the man has used many of these polymers as materials for providing clothing, decoration, tools, weapons and other requirements.

However, the origins of today’s polymer industry commonly are accepted as being in the nineteenth century when important discoveries were made concerning to the modification of certain natural polymers, as cellulose. The use of synthetic and natural polymers as stabilizers for colloid systems (sols, dispersions, microemulsions, etc.) is becoming more important everyday in contemporary life. Polymer additives can be applied in preconcentrations and dehydration of suspensions in mineral processing, purification of wastewater and even in nutritional and pharmaceutical emulsions being their importance related to the characteristics of the process and the properties that they show.

8. Переведите предложения на русский язык письменно.

1. The word «polymer» literally means «many parts».

2. A polymeric solid material may be considered to be one that contains many chemically bonded parts or units which themselves are bonded together to form a solid.

3. Two industrially important polymeric materials are plastics and elastomers.

4. Polymers are often named in terms of the monomer from which they are made.

5. Polymer signifies a chain of thousands of monomers that are covalently bonded together usually by the carbon atoms of the polymer backbone, but the backbone can consist of other atoms such as silicon.

6. Examples of polymers include substances anywhere from proteins to stiff, high-strength Kevlar fibers.

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