Discovering the Rich Heritage of Bio-Based Plastic Materials
Bio-based alternatives to petrochemical products are often viewed as a recent development to solely counter environmental concerns. Whilst there has certainly been a resurgence of interest in alternative raw materials, the concept is by no means new – their development has been influenced by a very different set of circumstances.
The first recognized example of bio-based plastic was created in 1862 by Alexander Parkes. Made from plant-based cellulose, the plastic was presented at a fair in London, England as a cheap alternative to rubber which was a harder resource to come by. As oil became one of the United States most important commodities in the second half of the 19th century however, the discovery of petrochemical polymers provided a cost effective alternative to the cellulose-based materials. It was not until the turn of the 20th century that the need for alternatives would lead to innovation. The arms race and mass industrialization that accompanied the escalation of tensions prior to World War One helped bring bio-based alternatives back into favour.
Material scarcity and the outbreak of war
We must cast our minds back to 1939 and the outbreak of the Second World War and the vast global mobilization of the world’s superpowers. The extent of the conflict meant that the demand for oil rose dramatically. By the time the United States joined the conflict in December of 1941, the war had spread to the oil-rich regions of the world. What had originally been a Europe-based conflict soon spread to countries with an abundance of oil, the North-African campaigns spreading across much Egypt, Iran and Saudi Arabia, centred on securing an oil supply. Oil wasn’t the only scarce resource: steel, which is relatively lightweight and structurally sound for use in a variety of mobility applications, was also hard to come by. In the absence of steel, which was being used to build military ships, planes and vehicles, finding ways to minimize its usage became essential.
Henry Ford and the Soybean Car
Prior to the outbreak of war for the United States, Henry Ford had presented his research team in Dearborn, Michigan the task of developing an automobile that utilized minimal petrochemical products and steel. The reasoning behind this project was that it would allow for the reduced usage of scarce materials needed for the war effort. In using raw materials procured from agricultural sources, Ford hoped to create lightweight, safer vehicles that could withstand crashes due to increased durability. The materials chosen for the experimental project were selected as they could be grown easily, locally and at a low cost.
Sadly, the precise formula used to create the polymers no longer exist, but it is believed that the ingredients included soybean and hemp fibres to create a resin. The usage of this bio-based resin did not eliminate the need for petrochemical polymers but drastically reduced the quantity needed to create a plastic component.
A major contributor to the development of soy based resin was George Washington Carver, the eminent agricultural scientist who began working closely with bio-based materials at the end of the 19th century. After years of experimentation he became friendly with Henry Ford; both men held the view that agricultural bioproducts were to play a key role in the future of North American manufacturing and so they joined forces to prove this to the rest of the country. By utilizing soy and hemp fibres as an additive (most likely a resin) in the creation of plastics, it was possible to heavily reduce the quantities of petrochemical materials required. The project proved so successful that in August of 1941 a prototype automobile known as the Soybean Car was showcased at a local fair. The car incorporated a lightweight steel chassis, but otherwise was largely made up of biobased plastic. The vehicle was roughly 1000lbs less than the standard steel car and Ford claimed that it was safer due to the robust nature of the plastic components.
With the outbreak of the war a mere four months after the Soybean Car was publicly introduced, domestic vehicle production was almost entirely halted in the United States. The country’s infrastructure had to be diverted into military applications and the building of tanks and military transport. Although research did continue during the war years, it was not possible to commercialize the vehicles successfully due to the government orchestrated shift towards military manufacturing. The production of plastics in the United States tripled between the years of 1940-45 as a lightweight alternative to steel. As oil was also hard to come by bio-based materials played an important role in many of these products including aircraft cockpits, tires and insulation.
After the war ended, the price of oil plummeted and there was a quick return to cheap petrochemical products. As we look towards a future that may well rely heavily on bio-based products due to the environmental impact and finite supply of petrochemical products, it is inspiring to know that nearly a century ago some of the biggest names of industry and science were able to make such progress. The latest 21st century developments in bio-based materials will be a key topic at the Foam Expo North America conference in March. Find out what Ford, Cargill, Keen and Evoco are up to today and what role bio-based materials play in the future of the foam industry.