Задание 6. Прочитайте, перепишите и письменно переведите текст.

Прочитайте, перепишите и письменно переведите текст.

Plastics

Many of us cannot imagine our life at present without plastics. Plastics are organic substances made synthetically by polymerization. You cannot go through a single day without some association with plastics: threads, sheets, tubes, combs and pens. They are durable and simple in production. Almost all plastics are produced from coal, air and water.

Plastics that consist of long-chain molecules can be softened by heat and molded into a desired shape. They are called thermoplastics. Plastics in which the polymer chains are cross-linked have much greater rigidity and cannot be softened readily. They are called thermosetting. The terms “thermoplastics” and “thermosetting” are also applied to the resins from which plastics are made. The resin may be natural, like cellulose, but it is most generally synthetic.

The resin is also known as the binder. Substances added to the plastic to enhance certain properties, e.g. hardness, resistance to shock or resistance to abrasion are called fillers; examples are asbestos, glass fibers and wood flour.

Plasticizers are also included in the formation. Antioxidants may be added to promote chemical stability and thus prolong life. Catalysts are added to assist the final cure (final formation of the product), and stabilizers to protect against sunlight, heat and other destructive factors.

II вариант

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