The birth of modern plastics
In 1907, Leo Hendrick Baekeland, a Belgian scientist working in New York, discovered and patented a revolutionary new synthetic material. His invention, which he named ‘Bakelite,’ was of enormous technological importance, and effectively launched the modern plastics industry.
The term ‘plastic’ comes from the Greek plassein, meaning ‘to mould’. Some plastics are derived from natural sources, some are semi-synthetic (the result of chemical action on a natural substance), and some are entirely synthetic, that is, chemically engineered from the constituents of coal or oil. Some are ‘thermoplastic’, which means that, like candlewax, they melt when heated and can then be reshaped. Others are ‘thermosetting’: like eggs, they cannot revert to their original viscous state, and their shape is thus fixed for ever. Bakelite had the distinction of being the first totally synthetic thermosetting plastic.
The history of today’s plastics begins with the discovery of a series of semi-synthetic thermoplastic materials in the mid-nineteenth century. The impetus behind the development of these early plastics was generated by a number of factors — immense technological progress in the domain of chemistry, coupled with wider cultural changes, and the pragmatic need to find acceptable substitutes for dwindling supplies of ‘luxury’ materials such as tortoiseshell and ivory.
Baekeland’s interest in plastics began in 1885 when, as a young chemistry student in Belgium, he embarked on research into phenolic resins, the group of sticky substances produced when phenol (carbolic acid) combines with an aldehyde (a volatile fluid similar to alcohol). He soon abandoned the subject, however, only returning to it some years later. By 1905 he was a wealthy New Yorker, having recently made his fortune with the invention of a new photographic paper. While Baekeland had been busily amassing dollars, some advances had been made in the development of plastics. The years 1899 and 1900 had seen the patenting of the first semi-synthetic thermosetting material that could be manufactured on an industrial scale. In purely scientific terms, Baekeland’s major contribution to the field is not so much the actual discovery of the material to which he gave his name, but rather the method by which a reaction between phenol and formaldehyde could be controlled, thus making possible its preparation on a commercial basis. On 13 July 1907, Baekeland took out his famous patent describing this preparation, the essential features of which are still in use today.
The original patent outlined a three-stage process, in which phenol and formaldehyde (from wood or coal) were initially combined under vacuum inside a large egg-shaped kettle. The result was a resin known as Novalak which became soluble and malleable when heated. The resin was allowed to cool in shallow trays until it hardened, and then broken up and ground into powder. Other substances were then introduced: including fillers, such as woodflour, asbestos or cotton, which increase strength and moisture resistance, catalysts (substances to speed up the reaction between two chemicals without joining to either) and hexa, a compound of ammonia and formaldehyde which supplied the additional formaldehyde necessary to form a thermosetting resin. This resin was then left to cool and harden, and ground up a second time. The resulting granular powder was raw Bakelite, ready to be made into a vast range of manufactured objects. In the last stage, the heated Bakelite was poured into a hollow mould of the required shape and subjected to extreme heat and pressure, thereby ‘setting’ its form for life.
The design of Bakelite objects, everything from earrings to television sets, was governed to a large extent by the technical requirements of the molding process. The object could not be designed so that it was locked into the mould and therefore difficult to extract. A common general rule was that objects should taper towards the deepest part of the mould, and if necessary the product was molded in separate pieces. Moulds had to be carefully designed so that the molten Bakelite would flow evenly and completely into the mould. Sharp corners proved impractical and were thus avoided, giving rise to the smooth, ‘streamlined’ style popular in the 1930s. The thickness of the walls of the mould was also crucial: thick walls took longer to cool and harden, a factor which had to be considered by the designer in order to make the most efficient use of machines.
Baekeland’s invention, although treated with disdain in its early years, went on to enjoy an unparalleled popularity which lasted throughout the first half of the twentieth century. It became the wonder product of the new world of industrials expansion — ‘the material of a thousand uses’. Being both non-porous and heat-resistant, Bakelite kitchen goods were promoted as being germ-free and sterilisable. Electrical manufacturers seized on its insulating properties, and consumers everywhere relished its dazzling array of shades, delighted that they were now, at last, no longer restricted to the wood tones and drab browns of the preplastic era. It then fell from favour again during the 1950s, and was despised and destroyed in vast quantities. Recently, however, it has been experiencing something of a renaissance, with renewed demand for original Bakelite objects in the collectors’ marketplace, and museums, societies and dedicated individuals once again appreciating the style and originality of this innovative material.
Complete the summary.
Choose ONE WORD ONLY from the passage for each answer.
Write your answers in boxes 1-3 on your answer sheet.
Some plastics behave in a similar way to 1……… in that they melt under heat and can be moulded into new forms. Bakelite was unique because it was the first material to be both entirely 2……… in origin, and thermosetting.
There were several reasons for the research into plastics in the nineteenth century, among them the great advances that had been made in the field of 3…………and the search for alternatives to natural resources like ivory.
Complete the flow-chart.
Choose ONE WORD ONLY from the passage for each answer.
Write your answers in boxes 4-8 on your answer sheet.
The Production of Bakelite
Questions 9 and 10
Choose TWO letters A-E.
Write your answers in boxes 9 and 10 on your answer sheet.
NB Your answers may be given in either order.
Which TWO of the following factors influencing the design of Bakelite objects are mentioned in the text?
A the function which the object would serve
B the ease with which the resin could fill the mould
C the facility with which the object could be removed from the mould
D the limitations of the materials used to manufacture the mould
E the fashionable styles of the period
Do the following statements agree with the information given in Reading Passage 1?
In boxes 11-13 on your answer sheet, write
TRUE if the statement agrees with the information
FALSE if the statement contradicts the information
NOT GIVEN if there is no information on this
11 Modern-day plastic preparation is based on the same principles as that patented in 1907.
12 Bakelite was immediately welcomed as a practical and versatile material.
13 Bakelite was only available in a limited range of colours.
关键词：similar/melt under heat
定位原文: 第2段倒数第2句“...like candlewax, they melt when heated...”
定位原文: 第2段最后1句“Bakelite had the distinction of being…”
关键词：the nineteenth century/advances/field/ivory
定位原文: 第3段第2句“The impetus…”
解题思路: 选用nineteenth century和ivory两个特殊词找到答案定位，然后再仔细寻找great advances的对应词immense technological progress，随后马上可以看到field的对应词domain。因此这道题目应该填chemistry。
关键词: avoid overcrowded centre
解题思路: instead是一个转折连接词，后面的观点与前者刚好相反。上一句说 pushing everyone into the city centre was not the best approach，刚好证明我们应该避免造成一个过度拥挤的市中心。
关键词： cotton / asbestos / catalysts
解题思路: 此处需要注意答案并不是woodflour，因为文中说 fillers such as woodflour, asbestos or cotton，后三者是作者举出的filler的具体例子，故不选。
定位原文: 第5段第4句的后半句“hexa, a compound…”
关键词： resin/cool/harden/break up/powder/bakelite
定位原文: 第5段第5句“This resin…”
关键词：mould /intense heat /cool
定位原文: 第5段最后1句“In the last stage…”
解题思路: extreme 和 intense 属于同义表达，空处和intense heat形成并列关系，答案很容易得出是pressure。
Question 9 & Question 10
定位原文: 第6段第2句“The object…”第6段第4句“Moulds had to be…”
解题思路: 第2句对应C选项，could not locked into 和题目的remove from 属于同义表达;第4句对应B选项，fill 和 flow completely into 也属于同义表达。
关键词：based on / the same
解题思路: 文中launch 一词实际上指的是1907年获得专利的技术开启了现代塑料工业的大门。所以答案应该是TRUE。这一点在最后一段中也能得到印证。
解题思路: 文中明确提到在其刚刚诞生的时候，酚醛塑料颇为大众所不屑，并不是立即就受到欢迎。下面的文章又提到 it then fell from favour again during the 1950s. immediately 一词过于绝对，一般在题目中出现该词选FALSE。
定位原文: 第7段第4句“...delighted that they were now, at last, no longer restricted to the wood tones and drab browns of the preplastic era.”
解题思路: 这句话告诉我们在塑料发展的初级阶段，人们只能买到木色和棕色的产品，但是随着技术的进步，人们不再限于这两种单调的颜色了。only 一词过于绝对，一般在题目中出现了该词选FALSE。