Soy Protein Plastic Back to Nature

Soy protein can be easily isolated from soybeans and molded. Soy plastics, which for a short period were used in automotive knobs and even body panels, never saw the widespread adoption predicted by Henry Ford in the 1930s. The Second World War sent his dream of growing a car like a crop into oblivion. Yet, as bio-based materials were being phased out by a growing synthetic, petroleum-based plastics industry, soy-protein plastics were being researched at the Ford Motor Company in Dearborn, Michigan, probably propelled by its leader Henry Ford s conscience, in an effort to give back to the American farmer what Ford tractors had taken away. 

Actually, soybeans were introduced to the United States from the Far East in 1804. They were grown more as a curiosity than a substantial crop until the First World War, when concerns about vegetable oil shortages made the oil-rich soybean an attractive crop. The success of extruded plastics from casein in the early 1900s spurred research into other agricultural sources of plastics, including plastics made from soy protein.By 1913 patents had been issued for preparing plastics from soy protein in Britain and France.The first US patent 

At the same time that the Ford Company was implementing its process for producing soy protein plastics, research into other techniques to make plastic parts from soybeans was ongoing at the US Regional Soybean Industrial Products Laboratory in Urbana, Illinois. From 1936 through 1942 the lab 

However, further experimentation indicated that instead of being truly thermoplastic, the pre-hardened soy-formaldehyde resin displayed thermoset and thermoplastic behavior, perhaps due to a long curing reaction.Work was needed to find a soy meal based material that was either thermoplastic enough to be injection molded or that would thermoset completely so it could be removed from a hot die. A variety of hardening agents were explored, with formaldehyde being the most effective in terms of low water absorption, followed by furfural, and propionaldehyde.  

The Second World War effectively put an end to the chemurgy movement, including Ford s desire to introduce large quantities of soy plastics into automobiles. After the Second World War, cheaper and better performing synthetic petrochemical based resins replaced soy and milk based protein plastics. 

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