The role of plasticizers in enhancing stability and texture

The concept of plasticization traces its origins to the 1860s, during a period of acute global ivory shortage caused by the booming popularity of billiards in Europe and North America. Traditional billiard balls were carved from elephant ivory, and besides its obvious and unnecessary brutality, supply could no longer meet demand. In 1863, the American inventor John Wesley Hyatt began experimenting with nitrocellulose, a rigid and brittle polymer. Pure nitrocellulose, however, was far too stiff and explosive for practical moulding.

Hyatt's breakthrough, patented in 1869—1870, was the addition of camphor as a plasticizer.¹ The resulting material, trademarked Celluloid, could be softened with heat and solvent, moulded under pressure into perfect spheres, and cooled, and hardened into a tough, glossy product. Celluloid became the first commercially successful thermoplastic and ushered in the plastics/plasticizer era.

The principle discovered by Hyatt, that certain additives can dramatically enhance polymer chain mobility without chemically altering the base polymer, rapidly found applications far beyond billiards.