To explore the relationship between societal needs and technological development through examining the history and making of synthetic rubber.
This lesson is part of the Energy in a High-Tech World Project, which examines the science behind energy. Energy in a High-Tech World is developed by AAAS and funded by the American Petroleum Institute. For more lessons, activities, and interactives that take a closer look at the science behind energy, be sure to check out the Energy in a High-Tech World Project page.
It was the Greek philosopher, Plato, who said that “necessity is the mother of invention.” Social and economic forces strongly influence which technologies will be developed and used. The events leading up to World War II accelerated the discovery, production, and wide distribution of synthetic rubber, in large part due to the cooperation between nations, academics, scientists, government, and commerce, which combined respective expertise to launch a program that replaced natural rubber with synthetic rubber and helped the United States win the war.
In this lesson, students will explore how events in history and scientific discoveries fuel technological advances and how technology is instrumental in creating new scientific knowledge. According to the National Science Education Standards, learning experiences associated with science and technology should include examples of technological achievement in which science has played a part and examples where technological advances contributed directly to scientific progress. (National Science Education Standards.) This lesson provides such an example in the case of the development of synthetic rubber.
When teaching this lesson, it is important to be aware of some student misconceptions surrounding science and technology. For one thing, students tend not to make a distinction between the two areas. Students often have a positive perception of science, as when they associate it with medical research. For technology, however, students often associate it with environmental problems. In addition, students seem to understand that science influences technology, but they do not readily accept that technology also influences science. (National Science Education Standards.)
To fully understand this lesson, students should have some understanding and knowledge about the events that led to WW II, particularly in relation to the development of synthetic rubber. They should have a basic understanding of how and why natural rubber was discovered, how it was used, and how its use led to the invention of synthetic rubber and its impact on the war effort.
It also would be helpful if before doing this lesson students understood that the physical properties of substances can be explained in terms of chemical bonds and intermolecular forces. They also should have an understanding of polymerization as a type of organic chemical reaction that joins small molecules to form large macromolecules. Students should understand that organic compounds contain carbon atoms that bond to one another in chains, rings, and networks to form a variety of structures.
Natural rubber is an elastic hydrocarbon polymer called polyisoprene and is found in the sap (latex) of certain trees. Synthetic rubber is made from polymers that are engineered synthetically by a process called polymerization, which is a chemical reaction produced when two or more molecules combine to form larger molecules with repeated structural units.
Ask students to use their Inventions of Necessity: Synthetic Rubber student esheet to read an article about natural rubber’s chemical structure, Meet Polyisoprene.
Using their esheet, students should then read about technologies invented to aid in expanding uses of natural rubber in the article Natural Rubber—History and Developments in the Natural Rubber Industry. Ask them to discuss in class how these technologies have affected the growth of the natural rubber industry.
Next, students should read the article What is Synthetic Rubber? and come to class prepared to answer and discuss these questions:
- Name ten industries that use synthetic rubber.
(Plastics, auto, shoes, tools, medical, transportation, textile, adhesives, aviation, and space are all industries that use synthetic rubber.)
- The article states that rubber in the modern world is omnipotent. What do you think the author meant by that statement?
(The author probably means that rubber has had a profound influence on science and industry, perhaps more than any other material.)
- What other inventions can you think of that have been invented out of necessity?
(Examples could include the upside down squeeze ketchup bottle; sliced bread; Velcro; the number zero. Low-Tech Inventions -- Or “Why didn’t I think of that?” lists several inventions that would help you initiate a fun discussion for this question.)
- What relation to natural or synthetic rubber do some of these other inventions have?
(The ketchup bottle and the loops in Velcro are made of plastic.)
During this discussion, ask students to look all around the classroom and name which objects in the room might contain rubber, or a derivative of it.
Ask students to use the student esheet to read the Brief History & Introduction of Rubber to understand how rubber has been one of the most influential products of all time. Then discuss these questions in class:
- What major factor led to the production of synthetic rubber?
(During WW II, the Japanese invaded Malaysia and the Dutch East Indies and gained control over their natural rubber production.)
- How did the rubber market shift from South America to Asia?
(In the late 1800s, seeds from Brazil rubber plantations were imported to England, germinated, and then shipped to Ceylon and Singapore. Most rubber trees in the Far East are descendents of these seedlings.)
- How did the advent of WW II change the course of rubber production?
(Rubber was essential to the production of U.S. war machinery, and when the Asian supply fell into the hands of the Japanese, the U.S. launched a massive effort to develop synthetic rubber.)
Ask students to write a brief summary of how natural rubber grew into an industry that sparked inventions of products and technologies that led to the manufacture of synthetic rubber.
Then, ask students to mind map the uses of rubber from 1525 to present day. They can use the Many Uses of Rubber student sheet to do this. Ask them expand the map by adding as many products as they can think of that have rubber in them or derivatives of rubber in their construction. Students can use the Brief History & Introduction of Rubber resource used earlier in the lesson to help them with this assignment.
Students can read Diamond-Like Hydrocarbons: Nanoscale Molecules with Diamond Structure Isolated from Petroleum and discuss in class how scientists’ discovery of these new materials paralleled scientists’ discoveries of synthetic rubber.
Use Silly Putty: Synthesizing a Polymer to access instructions for making Silly Putty and explaining the chemistry behind it.
Students can access An Introduction to the History of Plastics to learn about natural polymers. This site has links to more information about plastics, polymers, and related materials that students might find interesting.
For additional reading, hands-on activities, and tutorials, students can go to Faces in Polymers.