Internet Modeler Editorial: The Plastic We Love

By Chris Banyai-Riepl

The other day I came across an interesting headline that announced the discovery of a new plastic, and it led me to wonder about history of the plastic we all know and love so much. After a bit of digging, I found out some very interesting things about polystyrene and the plastic molding industry. Now many of us know that the first injection-molded plastic kits came from Frog in the mid-1930s, but how many know that the polystyrene plastic was actually discovered in 1839?

An apothecary named Eduard Simon was working with natural resins in 1839 when he isolated a substance that he did not know. While this was the initial discovery of polystyrene, it was not until much later that it was actually defined as such. It took another German scientist, this time an organic chemist named Hermann Staudinger, to figure out in 1922 what Simon's discovery actually was: a plastic polymer made up of long chains of styrene molecules.

Around the same time, a Belgian scientist, Dr. Leo Baekeland, in the search for a less flammable floor shellac for bowling alleys, discovered phenolic resin, an insoluable and infusible resin with immense potential. In 1910, after patenting this discovery, Dr. Baekeland started in the Bakelite Corporation. What does this have to do with polystyrene, you ask? Well, one of the great aspects of phenolic resin, or Bakelite, was its ability to be molded into just about any shape. The process was simple: take a sheet of Bakelite, grind it into a fine powder, then push it into a mold using high heat and pressure. Here are the beginnings of injection molding, and it was only a matter of time before Simon and Staudinger's polystyrene met up with an advanced form of Bakelite's molding process.

Before we get to that, though, enter Frog Penguin and their first plastic kits. These first kits were not made from polystyrene, but rather cellulose acetate, an organic thermoplastic. These early kits had amazing detail compared to the wood kits that came before, although there were some problems. The most notable one was with warping. Because cellulose acetate was so sensitive to heat, great care had to be taken in molding it. If the finished product was removed from the mold too soon, it would warp. To make matters worse, this warpage could show up days or even weeks after removal! Before this issue could be solved, though, the Second World War got in the way, and plastic technology, like many other technologies, got a huge jump forward.

Following the Second World War, a whole slew of new plastics rose up and replaced phenolic resins and cellulose acetate. Plastics such as vinyl and polystyrene took over, and injection processes had improved along with the plastic technology. In 1955, Frog came out with its first polystyrene plastic kit. Other companies such as Airfix and Revell had already made that leap, and by the 1960s, polystyrene was pretty much the only plastic used for model kits around the world, and continues to this day.

Is this the end of the plastic story? Perhaps not, as a team of scientists have discovered a possible new plastic that could replace polystyrene. The main issue with polystyrene is that it is based on petroleum byproducts, which eventually will run out. Working solely with renewable resources, Professor Geoffrey Coates at Cornell University came up with a new plastic, polylimonene carbonate. This plastic uses orange oil and carbon dioxide, both of which are in plentiful supply and easily renewable. Now whether this means our next big model purchase will come off the shelves smelling like oranges remains to be seen, but science does march forward and who knows what the future will hold for our hobby.