QenosCnr Kororoit Creek Rd and Maidstone St, Altona 3018

Ph 61 3 9258 7333 Fax 61 3 9369 6624

This is a chapter from the

Chemistry

Resource Kit

The Qenos Chemistry Resource kit has been developedas an information package for secondary students andothers who wish to learn about Qenos, plasticsmanufacturing and the petrochemical industry.

This document is available on the Qenos website at: www.qenos.com

Published by Qenos Corporate Affairs Department,Dec 2001 ACN 054 196 771

Introduction to Qenos Elastomers s Qenos Resource Kit s Page 1

Introduction to Qenos Elastomers

Qenos Elastomers’ success is closely related tothe fortunes of the Australian tyre industry.

Figure 1 illustrates the range of products whichcontain synthetic rubber. It also shows that themajority of Qenos Elastomers’ production is usedin tyres, i.e. 85%.

In 1960, polybutadiene rubber (BR) was introducedin the USA. BR has played an important part inmeeting the increasing performance demands ofthe tyre industry.

Initially, polybutadiene was used as a superiorreplacement for natural rubber in heavy-duty truckand bus tyres. Today BR is used in blends withSBR and natural rubber for passenger and lighttruck tyres.

SBR and BR offer a wide spectrum of properties.These properties can be tailored to meet a rangeof applications. For example, a passenger cartyre contains various blends of SBR, BR, naturalrubber and special elastomers. This helps the tyremanufacturers to produce a range of tyres suitedto many different applications.

Qenos Elastomers was the first company inAustralia to produce synthetic rubber. Today itremains as the sole producer of BR in theAustralia. The production of BR rubber isexamined in detail in the section ‘Production ofBR’.

History of RubberThe history of natural rubber and the efforts thatled to the successful development of its partner,synthetic rubber, are worth noting. The historiesof each are linked. It is a story rich in scientificdiscovery and technological innovation.

History of Natural Rubber1492Christopher Columbus found natives on the eastcoast of South America playing with a blackheavy ball made of vegetable gum whichbounced. Several pieces were taken back toQueen Isabella of Spain where they createdmuch interest. Natural rubber had beendiscovered by Europeans but remained only acuriosity for three centuries.

1739La Condamine, a French explorer, reported to theFrench Academy of Science about a materialused by the natives of the Amazon to make shoes

History of Synthetic RubberDevelopment in AustraliaCommercial production of synthetic rubber beganin 1915 in Germany. The first commercialsynthetic rubber was methyl rubber producedfrom dimethylbutadiene during World War I whentwo and a half thousand tons of methyl rubberwas produced.

Between the world wars the low price of naturalrubber stifled interest in synthetic rubbers. Theadvent of World War II restricted natural rubbersupplies once again. This led to the furtherdevelopment of synthetic rubbers in Germany andAmerica.

Styrene-butadiene rubber (SBR) productionbegan in the USA in the 1940s. Today, styrene-butadiene rubber (SBR) is the most important andwidely-used synthetic rubber in the world.

By the 1950s, synthetic rubber was one ofmodern society’s key raw materials and Australianeeded its own inexpensive and reliable supply,preferably from local manufacture.

On 26 March, 1958, Australian Synthetic RubberCompany Limited (now Qenos Elastomers) wasborn.

Work began on the company’s 12 hectare(30 acre) site in March 1960, and, in October1961, the first production run of SBR came off theline.

A second plant was commissioned in May 1967to produce solution polymerised high cispolybutadiene rubber (BR).

In 1971, facilities were further upgraded when thefinishing lines were expanded, greatly increasingplant capacity, and sales peaked in 1973 at nearly34,000 tonnes.

Since it began, Qenos Elastomers has met thediverse needs of hundreds of Australianindustries. Today, over half the rubber used inAustralia is synthetic, and of this total, 80% isSBR/BR.

In 2001, Qenos shutdown its SBR manufacturingoperations. Qenos now manufactures BR rubberand distributes SBR rubber.

Qenos Elastomers relies on Qenos Olefins for thebasic raw material butadiene. Qenos Elastomerscan manufacture up to 12,000 tonnes of BR rubberper year—enough for millions of car tyres.

The tyre industry consumes 80% of all rubber.

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Introduction to Qenos Elastomers s Qenos Resource Kit s Page 3

and bottles. This material was obtained by a treeknown as ‘Caoutchouc’ or ‘Weeping Wood’.

1770Joseph Priestly reported that he had examined asubstance ‘excellently adapted to the purpose ofwiping from paper the marks of a black leadpencil’ he suggested that this substance whichoriginated from Brazil should be called ‘rubber’.

Early 19th CenturyCharles MacIntosh made use of rubber’swaterproof qualities by spreading rubber overfabrics and making raincoats.

1820Thomas Hancock invented the ‘pickle’ or‘masticator’ which enabled rubber to be softenedso as to be easier to dissolve in turpentine orNaphtha for making solutions.

1839Charles Goodyear, a young American inventor,discovered that when sulphur was mixed intorubber and the mixture subjected to heat it wouldvulcanize. About the same time Thomas Hancockmade the same discovery in England.

1846The Englishman Robert Thomson demonstratedthat a leather thread fitted to a pneumatic rubbertube reduced skidding and noise on horse drawnvehicles and also greatly increased traction.

Originally the crude rubber was obtained fromwild rubber trees in South America and Africa.Brazilian rubber had to be transported 4800kilometres by porterage, and canoe before itreached a port for shipment. This meant that itcould take up to a year for rubber to reach themanufacturer.

As demand for rubber increased, its costincreased. It was clear that wild rubber treeswould not be able to supply the growing demandfor rubber.

1869James Collins published the papers, 'IndiaRubber—Its History, Commerce and Supply'. Healso published a report on the Caoutchoucs ofAmerica with illustrations of various forms oftapping, including the herring bone method. Theherring bone method, see figure 2, is still usedtoday.

1873James Collins wrote to a Mr. Farris in Brazil whosent 2000 seeds to Kew Gardens from which only12 germinated. Of these seedlings some weresent to Calcutta and Burma.

Figure 2Tapping a rubber tree

1873Henry Wickham, a grower of sugar and tobaccowho was living in Brazil was requested by theBritish India Office to obtain rubbers seeds. Afterconsiderable negotiation regarding the price,Wickham agreed to collect seeds at the price of10 pounds per 1000.

1876 JulyWickham delivered 70,000 seeds to KewGardens where only 2,397 germinated.

1876 AugustThe germinated rubber plants were dispatchedfrom Kew, 2000 being sent to Ceylon, also someto Singapore but those latter plants were dead onarrival.

1877 JulySome 22 rubber plants were received atSingapore Botanical Gardens. From these 22trees over 75% of all the cultivated rubber treeshave grown.

1888Over 1000 trees were ready to tap in theEconomic Gardens, Singapore, but no one wasinterested in the potential production of naturalrubber. At this time Henry Ridley became directorof the Singapore Botanical Gardens and attemptedto interest people in the cultivation of rubber.

1889John Boyd Dunlop produced a rubber tube with aone way valve, covered it with canvas andcemented it to the wheel of his bicycle. He formedthe Dunlop Rubber Co. to manufacture thispneumatic tyre.

First plantation rubber trees were tapped.

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History of Synthetic RubberDevelopment

1826Faraday established that the empirical formula fornatural rubber was (C5H8)n.

1879Bouchardt obtained isoprene from natural rubberby distillation, treated it with hydrochloric acid andobtained a tough elastic rubber like solid.

1910Mathew and Strange in England and Harries inGermany discovered that isoprene could bepolymerized with sodium to produce syntheticrubber.

1911Kyriakides in U.S.A. found that dimethylbutadiene or pure isoprene could be more easilypolymerized with sodium than the previously usedrather impure isoprene.

1912The German Company Bayer obtained a patentfor the emulsion polymerization process withisoprene.

1914World War I

Germany commercially manufactured syntheticrubber by placing dimethylbutadiene and sodiumin a drum which was stored at 30°C for 6-10weeks. This rubber was known as Methyl rubberH and was used in hard rubber articles. For softrubber goods Methyl rubber W was used, thismaterial was obtained from dimethyl butadieneheated in pressure vessels for 3 to 6 months at70°C. During this wartime period Germanyproduced 2,350 tons of Methyl Rubber.

1923U.S. Rubber Co produced synthetic rubber frombutadiene using an emulsion polymerisationprocess.

1926–28In Germany extensive work was undertaken todetermine the best process for polymerisationand the emulsion polymerisation process wasperfected.

1933German chemists developed the copolymerisationof butadiene with styrene (Buna S Rubber) or withacrylonitrile (Buna N Rubber).

Concurrently with these developments in Germany,many other countries were showing an interest insynthetic rubbers.

1896First plantation rubber was sent to England andsold for 2/8d per pound.

1914World War I

Demand for natural rubber increases.

Germany begins experimenting with theproduction of synthetic rubber.

1941—45World War II

During World War II ninety per cent of theworld’s natural rubber was controlled by theJapanese. To overcome this rubber shortage theUSA spent a billion dollars on developingsynthetic rubber production. This program wassecond only to the development of the atomicbomb.

By 1943, synthetic rubber was being producedin 100 plants across the USA.

1950s to todayRubber is now one of the major worldcommodities. Natural rubber remains a keyexport crop for countries in Asia, Malaysia,Indonesia and Thailand.

Natural Rubber Statistics

Year Production Rest (in tons)

S.E Asia

1900 500 44,500

1910 11,000 84,000

1920 305,000 37,500

1921 277,500 25,000

1930 804,000 21,000

1932 700,500 9,500

1940 1,372,500 45,000

1949 1,416,000 74,000

1950 1,777,500 82,500

1951 1,780,000 105,000

1960 1,832,500 165,000

1969 2,637,000 217,000

Introduction to Qenos Elastomers s Qenos Resource Kit s Page 5

Types of RubberThere is essentially only one chemical type ofnatural rubber. The variety of physical propertiesfound in different natural rubber products is theproduct of plantation processing. The basicpolymer—a cis-1,4-polyisoprene—is the samewhether it comes from Hevea brasiliensis or fromany other type of rubber tree.

In contrast to this, different synthetic rubbers arechemically different.

A variety of chemicals are used to make syntheticrubbers. They include butadiene, styrene,chloroprene, ethylene, isobutylene, etc.

These monomers are polymerized to producesynthetic rubbers. They can be polymerized ontheir own to form the polymer, as in the case ofpolybutadiene and polychloroprene. Or they canbe co-polymerized as in the case of styrenebutadiene rubber (SBR), or ethylene propylenediene rubber (EPDM).

Each synthetic rubber has its range of propertieswhich make it ideal for a range of applications.For each type of synthetic rubber there are manydifferent grades. They differ in:

n method of production

n length of the rubber molecules

n types of additives present

These different grades further extend the rangeof applications for that type of rubber.

Natural rubber is still widely used. Natural rubberrepresents one third of the rubber consumedworldwide. Of the synthetics SBR is about onethird of consumption and BR about one sixth. Intotal over eleven million tonnes of rubber wasconsumed in 1991.

Further informationRefer also to the sections:

n Production of BR(Chapter 8)

n Waste Rubber(Chapter 11)

1924–30Patrick in U.S.A. found that sodium tetra-sulphide could be reacted with ethylene dichlorideto form a rubbery solid. This material was firstcommercially marketed in 1930 as Thiokol.

1925–31Dupont announced a new synthetic rubber madefrom chloroprene and called it Duprene. Thisname was later changed to Neoprene whichbecame commercially available in 1931.

1937–43Sparks and Thomas of Esso Research andEngineering copolymerised isobutylene withisoprene and obtained a vulcanisable rubber likematerial which was known as Butyl and becameavailable in 1943.

1939–45

World War II Synthetic RubberProduction*

1940 1944

Germany U S A Germany U S A(tons) (tons) (tons) (tons)

37,137 — 110,568 670,268

* Production of Butadiene-styrene (Buna S GRS or SBR)

By the end of 1945, the US Government had built17 synthetic rubber plants, producing over800,000 tons of synthetic rubber per annum.

1937–44Silicone. Kipping reviewed the developments inorganic silicone polymers and forecasted nouseful future for these materials. Seven yearslater silicone rubbers were marketedcommercially and found ready acceptance in hightemperature application.

1954–59Polyisoprene. Goodrich announced thesuccessful synthesis of natural rubber however inthe following year Firestone revealed that they hadproduced their “Coral rubber” in 1953. Commercialquantities became available in 1960.

1956–60Ethylene-Propylene Copolymers developed byMontecatini. Natta, an Italian chemist extendedthe use of Ziegler catalysts.