The Plastic Age

PART 3 PLASTICS

UNIT 1

Read the text:

The Plastic Age

It’s in our homes. It’s the most common material in the workplace. Sometimes it’s even in our bodies. We may be moving into the Information age, but it’s hard to believe that we are not living in the Plastic Age.

The very name “plastic” means versatility. You can bend it, mold it, model it, twist it and ply it in a number of different ways. The finished product can be soft and airy foam. In its many forms, plastic has forever changed the way we live.

The first in the long line of man-made plastics was called Bakelite, after its inventor, Leo Baekeland. Many years of work in his chemistry lab in Yonkers, New York, led him in 1907 to the invention of the first synthetic polymer (plastic), made by linking small molecules together to make large ones.

Baekeland made his new material by mixing the carbolic acid (phenol) with the strong-smelling formaldehyde to make a third material that was nothing like the original two. It turned out to be a substance that would change the world.

Some of the early uses for plastic were to make things like radio cabinets, buttons, billiard balls, airplane parts and, the object of Baekeland’s research, shellac. Baekeland’s trick was to take the resin produced by the two chemicals and heat it under pressure to produce a soft solid that could be molded and hardened or powdered and set under pressure. With this innovation, the plastic revolution was under way.

Plastics provide a very necessary and important role in society, not only through energy savings in construction, but making leisure more enjoyable and affordable, enabling communications and supporting a revolution in health care needs.

Plastic is essential for thousands of applications from life-saving medical devices like blood bags, heart valves and hip joints to the packaging which protects manufactured goods from damage and preserves our food - saving on waste and helping keep retail prices down. Plastic is also essential in every aspect of modern living, providing us with the means to communicate in products ranging from mobile phones to lightweight laptops.

Assignments:

I. General understanding. Answer the questions:

1. Why is it hard to believe that we are not living in the Plastic Age?

2. What can you do with plastic?

3. Who invented the first synthetic polymer?

4. What is the process of making plastic?

5. What is the Baekeland’s trick?

6. What are the properties of plastics?

7. What are the first man-made plastics?

8. What are the early / modern uses of plastic?

II. Translate these words and phrases into Russian:

Heat under pressure; providing us with the means; carbolic acid; health care needs; synthetic polymer; strong-smelling formaldehyde; workplace; trick; man-made plastics; energy savings in construction; essential in every aspect of modern living; finished product; turned out to be a substance; lightweight laptops; versatility; soft solid; under way; protect manufactured goods from damage; chemistry lab.

III. Paraphrase the following sentences, using simple language:

1. We may be moving into the Information age, but it’s hard to believe that we are not living in the Plastic Age.

2. Plastics provide a very necessary and important role in society, not only through energy savings in construction, but making leisure more enjoyable and affordable, enabling communications and supporting a revolution in health care needs.

3. Many years of work in his chemistry lab in Yonkers, New York, led him in 1907 to the invention of the first synthetic polymer (plastic), made by linking small molecules together to make large ones.

4. Baekeland made his new material by mixing the carbolic acid (phenol) with the strong-smelling formaldehyde to make a third material that was nothing like the original two.

IV. Say whether these sentences are true (T) or false (F):

1. Leo Baekeland invented the second synthetic polymer.

2. We are moving only in the Information Age.

3. You can do almost everything with the plastic.

4. Plastic will change the world.

5. Baekeland’ trick was to produce a soft solid.

V. Ask general questions to these sentences:

1. It’s the most common material in the workplace.

2. The very name “plastic” means versatility.

3. We may be moving into the Information age.

VI. Ask special questions to the following sentences:

1. Plastic has forever changed the way we live.

2. Many years of work in his chemistry lab in Yonkers, New York, led Leo Baekeland in 1907 to the invention of the first synthetic polymer (plastic), made by linking small molecules together to make large ones.

3. Some of the early uses for plastic were to make things like radio cabinets, buttons, billiard balls, airplane parts and, the object of Baekeland’s research, shellac.

VII. Make up in English an obtaining scheme of: a) bakelite; b) shellac.

Initial material → process → result → properties

VIII. Read the text. Divide the text into paragraphs. Speak about plastics using your own plan as well as the following phrases:

This article is about / the author of the article speaks about … 2. I’d like to call your attention to … 3. One should mention that … 4. It’s interesting to point out that … 5.One should comment upon this question / problem … 6. So / besides / moreover / that is why … 7. On the one hand / on the other hand … 8. In conclusion, I can say that … 9. Considering all the facts …

Plastics

Plastics are large and varied group of materials consisting of combinations of carbon and oxygen, hydrogen, nitrogen, and other organic and inorganic elements. While solid in its finished state, a plastic is at some stage in its manufacture, liquid and capable of being formed into various shapes. Forming is usually done through the application either singly or together, of heat and pressure. There are over 40 different families of plastics in commercial use today, and each may have dozens of subtypes and variations.

A successful design in plastics is always a compromise among highest performance, attractive appearance, efficient production, and lowest cost. Achieving the best compromise requires satisfying the mechanical requirements of the part, utilizing the most economical resin or compound that will perform satisfactorily, and choosing a manufacturing process compatible with the part design and material choice.

Most people have now outgrown the impression that plastics are low cost substitute materials. Those that still view plastics as cheap and unreliable have not kept up with developments in polymer technology for the past ten years.

Many plastics did indeed evolve as replacements for natural products such as rubber, ivory or wood, which became unavailable or on short supply. But the new materials did not necessarily replace the older ones permanently nor made them obsolete. In many cases, they met an increased demand that could not be met by the natural product alone.

Today’s engineering resins and compounds serve in the most demanding environments. Their toughness, lightness, strength, and corrosion resistance have won many significant applications for these materials in transportation, industrial and consumer products. The engineering plastics are now challenging the domains traditionally held by metals: truly load bearing, structural parts.

UNIT 2

I. Look at the pictures of plastic products. Discuss why plastic has been chosen for each of these items?

EXAMPLE:

Plastics are used for fuel tanks because they are resistant to chemicals. Fuel tanks have to be strong and last a long time, and plastics are durable.

II. Make a list of the properties of plastics that make them suitable materials for such a wide range of products.

III. CD Tape-3. Listening. “The History and Properties of Plastics”

1) What were the first plastics made from? What are plastics produced from today?

2) Listen to two Technology students talking about plastics. As you listen, complete the table of raw materials and the plastics made from them.

3) Listen again and note the advantages and problems with each of the different types of plastic, as well as recycled plastic – 4.

Read the text:

Thermoplastics

Types of Plastics (Part I)

Plastics are non-metallic, synthetic, carbon-based materials. They can be molded, shaped, or extruded into flexible sheets, films, or fibers. Plastics are synthetic polymers. Polymers consist of long-chain molecules made of large numbers of identical small molecules (monomers). The chemical nature of a plastic is defined by the monomer (repeating unit) that makes up the chain of the polymer. Polyethene is a polyolefin; its monomer unit is ethane (formerly called ethylene). Other categories are acrylics (such as polymethylmethacrylate), styrenes (such as polystyrene), vinys (such as polyvinyl chloride (PVC)), polyesters, polyurethanes, polyamides (such as nylons), polyethers, acetals, phenolics, cellulosics, and amino resins. The molecules can be natural-like cellulose, wax, and natural rubber – or synthetic – in polyethene and nylon. In co-polymers, more than one monomer is used. The giant molecules of which polymers consist may be linear, branched, or cross-linked, depending on the plastic. Linear and branched molecules are thermoplastic (soften when heated), whereas cross-linked molecules are thermosetting (harden when heated).

Most plastics are synthesized from organic chemicals or from natural gas or coal. Plastics are lightweight compared to metals and are good electrical insulators. The best insulators now are epoxy resins and Teflon. Teflon or polytetrafluoroethene (PTFE) was first made in 1938 and was produced commercially in 1950.

Plastics can be classified into several broad types.

Thermoplastics soften on heating, and then harden again when cooled. Thermoplastics molecules are also coiled and because of this they are flexible and easily stretched.

Typical example of thermoplastics is polystyrene Polystyrene resins are characterized by high resistance to chemical and mechanical stresses at low temperatures and by very low absorption of water. These properties make the polystyrenes especially suitable for radio-frequency insulation and for parts used at low temperatures in refrigerators and in airplanes. PET (polythene terephthalate) is a transparent thermoplastic used for soft-drinks bottles. Thermoplastics are also viscoelastic, that is, they flow (creep) under stress. Examples are polythene, polystyrene and PVC.

Thermosetting plastics (thermosets) do not soften when heated, and with strong heating they decompose. In most thermosets final cross-linking, which fixes the molecules, takes place after the plastic has already been formed.

Thermosetting plastics have a higher density than thermoplastics. They are less flexible, more difficult to stretch, and are less subjected to creep. Examples of thermosetting plastics include urea-formaldehyde or polyurethane and epoxy resins, most polyesters, and phenolic polymers such as phenol-formaldehyde resin.

Elastomers are similar to thermoplastics but have sufficient cross-linking between molecules to prevent stretching and creep.

Assignments:

IV. General understanding. Answer the questions:

1. What is the basic chemical element in plastic formula?

2. What do polymers consist of?

3. What are the main types of polymers?

4. Which plastics are the best electrical insulators?

5. Describe the difference between thermoplastics and thermosets.

6. What are the main types of structures of polymers?

7. Give the examples of various uses of plastics because of their characteristic properties.

V. Find the English equivalents in the text:

Синтетические полимеры; молекулы с длинными цепями; характерные свойства полимера; синтезируются из органических химических веществ; хороший электрический изолятор; размягчаться при нагревании; затвердевать при охлаждении; гибкий и легко растяжимый; течь под нагрузкой; более высокая плотность; менее подвержены ползучести; достаточная взаимосвязь между молекулами.

VI. Say whether these sentences are true (T) or false (F):

1. Polymers consist of long-chain molecules made of large numbers of not similar monomers.

2. Thermosets always soften when heated and decompose with strong heating.

3. The molecules may be of two kinds.

4. Practically all plastics are synthesized from inorganic chemicals.

5. Thermoplastics and elastomers are similar but the latter has sufficient cross-linking between molecules.

6. Teflon was first made in XIX century.

7. The basic chemical element in plastics is carbon.

VII. Match the adjectives and nouns as they go in the text:

VIII. Some words are often used together. Fill the gaps in sentences 1-6 with a word from the list that often goes with the word in bold.

1. Oil and natural gas are the main raw ___ used in the production of plastics.

2. Compression moulding is one example of a production ___.

3. Plastics are used in the production of a wide range of household ___.

4. Reinforced plastics are a major building material in the construction __.

5. The car industry uses high-precision ___ in their vehicles.

6. The majority of plastics are manufactured using injection ___.

IX. Translate the following sentences into English, using the information from the text:

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

2. Сополимеры состоят из двух и более мономеров.

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

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

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

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

7. Эластомеры имеют большое число поперечных связей между молекулами.

UNIT 3

Read the text:

Types of Plastics (Part II)

1. Epoxy resin.

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.

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.

2. PVC (polyvinyl chloride).

PVC 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.

3. Polystyrene.

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.

4. Polythene (polyethene, polyethylene).

Polythene 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 200⁰C. 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.

Assignments:

I. General understanding. Answer the questions:

1. What are the types of plastics?

2. What are the features of the epoxy resin?

3. What is PVC usually used for?

4. What are typical applications of polystyrene?

5. When was polyethene synthesized?

6. Under what conditions is polyethylene synthesized?

7. What sorts of polyethylene can be synthesized?

II. Find the English equivalents to the following Russian words from the text:

Бесцветное твёрдое тело; жёсткость; выдувка; широко используемый; эпоксидные смолы; изоляция; великолепная устойчивость к воздействию воды; упаковка; низкая плотность; строительство лодок; смешиваться с отвердителем и пластификатором; прессованные листы; воскообразное вещество.

III. Ask general questions to the following sentences:

1. Polythene is a plastic made from ethane.

2. Epoxy resins have outstanding adhesion, toughness and resistance to attack from the chemicals.

3. PVC is a colourless solid with outstanding resistance to water, alcohols, and concentrated acids and alkalis.

4. Polystyrene is a thermoplastic produced by the polymerization of styrene.

5. Typical applications include light fixtures, toys, bottles, lenses, capacitor dielectrics, medical syringes, and light-duty industrial components.

IV. There are well over a thousand different plastics. Work in pairs and match up the codes with the names of these most widely-used plastics:

V. Webquest:

1) Try to find the names and codes of other plastics. These sites may help:

· www.bpf.co.uk;

· www.eng.morgan.edu.

2) Where would you find the following symbols?

3) What do they mean and what is their purpose? These sites may help:

· www.pac-it.org;

· http://americanplasticscouncil.org.

VI. Translate the following texts from English into Russian in written form:

Raw Materials

Originally, most plastics were made from resins derived from vegetable matter, such as cellulose (from cotton), oils (from seeds), or coal. Casein (from milk) was among the nonvegetable materials used. Although the production of nylon was originally based on coal, air, and water, and nylon is still based on oil from castor beans, most plastics today are derived from petrochemicals. These oil-based raw materials are relatively widely available and inexpensive. However, because the world supply of oil is limited, other sources of raw materials, such coal gasification, are being explored.

Epoxy Resins

Epoxy resins have outstanding mechanical properties, dimensional stability, resistance to heat and chemicals, and adhesion to other materials. They are used for casting, protective coating, and adhesives, and for reinforced moldings and laminates of the highest quality. Popular adhesives (epoxy glues) contain the resin components and the curing agent, usually an amine or an anhydride, in separate packages. The two are mixed just before use.

VII.Render the text in English:

Шёлк чистой науки: Нейлон

В середине 1920-х главный химик компании DuPont Чарльз Стайн организовал экспериментальную лабораторию фундаментальных исследований - «Зал чистой науки» (Purity Hall). Стайн переманил из университетов несколько молодых талантов, одним из которых стал Уоллас Карозерс, гений органической химии из Гарварда, возглавивший программу исследований в области полимеризации. В то время о химии полимеров было известно не много. Немецкий химик Герман Штаудингер считал, что молекулы полимера - это длинные цепочки, сцепленные между собой, а другая, доминирующая в то время теория, говорила, что маленькие молекулы собираются в агрегаты и удерживаются пока неизвестными силами. «Разбирая» полимеры, доказать правоту той или иной теории было невозможно, поэтому Карозерс, сторонник теории Штаудингера, занялся синтезом.

В апреле 1930 года сотрудник Карозерса Джулиан Хилл в результате синтеза полиэфиров получил вязкую массу, из которой можно было вытянуть длинные эластичные и прочные нити. Но в быту они были бесполезны - не выдерживали воздействия горячей воды и даже не слишком высокой температуры. Поэтому Карозерс переключился на исследования в области полиамидов. Со своим помощником Доном Коффманом он перебрал более 80 комбинаций кислот и аминов с целью получить суперполимер. И вот, наконец, 27 июля 1934 года Уэсли Петерсон получил соединение «полимер 5-10» (пять атомов углерода в составе амина и десять - в составе кислоты) с прекрасными потребительскими качествами. Однако Элмер Болтон, сменивший к тому времени Стайна на посту главного химика, забраковал материал.

Единственным источником одного из исходных веществ было касторовое масло, доступное в лабораторных масштабах, однако при массовом выпуске материал стал бы «золотым». Прошло еще семь месяцев исследований, и 28 февраля 1935 года Жерар Берше наконец получил из гексаметилендиамина и адипиновой кислоты «полимер 6-6» (или просто «66»). Он не был так хорош, как «5-10», поскольку имел более высокую температуру плавления, что затрудняло его производство. Но зато исходные вещества были дешевы и доступны в промышленных количествах.

Из более 350 предложений названия для «волокна 66» - от аббревиатур Duparooh (DuPont Pulls a Rabbit Out Of the Hat - «DuPont вынимает кролика из шляпы») до Dusilk и Silkex, подчёркивающих сходство с шёлком, - было выбрано слово nuron. Но оно звучало слишком «нейроанатомично», и его свели к nilon, а чуть позже - для благозвучности - к знаменитому nylon.

В 1938 году новое волокно было анонсировано на Всемирной выставке в Нью-Йорке. Первое применение материал нашёл в качестве щетины для зубных щёток, но свою славу нейлон получил благодаря женским чулкам. Популярность их была столь велика, что в 1940 году, когда состоялись первые общенациональные продажи, пять миллионов пар было продано за один день. К сожалению, Карозерс, ставший в 1936 году первым ученым из промышленности, избранным в Национальную академию наук, не дожил до триумфа нейлона - 29 апреля 1937 года, всего через два дня после своего 41-го дня рождения, он, страдая от депрессии, принял смертельную дозу цианида. Его друзья считали, что он просто боялся, что ему больше никогда не придет в голову гениальная идея, сравнимая с изобретением нейлона.

«Популярная механика»

Use the words and phrases given below:

Переманивать - entice away; органическая химия - organic chemistry; полимеризация polymerization; в быту – in everyday life; воздействие горячей воды – hot water action; состав – composition; потребительские качества – consumer properties; касторовое масло - castor oil; гексаметилентетрамин – hexamethylenetetramine; адипиновая кислота - adipinic acid; щетина для зубных щёток - bristle for teeth brushes; женские чулки - women stockings; страдать от депрессии – suffer from depression.

UNIT 4

Read the text: