Different forms of all sorts of things were coming out of refineries, driven in part by the demands of war. Houdry had also invented a catalytic process for crude oil that yielded butadiene, a hydrocarbon compound with some interesting characteristics. In the years before and during World War II it became one of two key ingredients in the production of synthetic rubber, an especially vital commodity as the war in the Pacific cut off supplies of natural rubber. The stage was now set for a revolution in petrochemical technology. As the war drove up demands for both gasoline and heavier aviation fuels, supplies of byproduct compounds—known as feedstocks—were increasing. At the same time, chemical engineers working in research labs were finding potential new uses for just those feedstocks, which they were beginning to see as vast untapped sources of raw material.
Throughout the 1920s and 1930s and into the 1940s chemical companies in Europe and the United States, working largely with byproducts of the distillation of coal tar, announced the creation of a wide assortment of new compounds with a variety of characteristics that had the common property of being easily molded—and thus were soon known simply as plastics. Engineering these new compounds for specific attributes was a matter of continual experimentation with chemical processes and combinations of different molecules. Many of the breakthroughs involved the creation of polymers—larger, more complex molecules consisting of smaller molecules chemically bound together, usually through the action of a catalyst. Sometimes the results would be a surprise, yielding a material with unexpected characteristics or fresh insights into what might be possible. Among the most important advances was the discovery of a whole class of plastics that could be remolded after heating, an achievement that would ultimately lead to the widespread recycling of plastics.
Three of the most promising new materials—polystyrene, polyvinyl chloride (PVC), and polyethylene—were synthesized from the same hydrocarbon: ethylene, a relatively rare byproduct of standard petroleum refinery processes. But there, in those ever-increasing feedstocks, were virtually limitless quantities of ethylene just waiting to be cracked. And here also was a moment of serendipity: readily available raw material, a wide range of products to be made from it, and a world of consumers coming out of years of war eager to start the world afresh, preferably with brand-new things.
Plastics and their petrochemical cousins, synthetic fibers, filled the bill. From injection-molded polystyrene products like combs and cutlery, PVC piping, and the ubiquitous polyethylene shopping bags and food storage containers to the polyesters, the acrylics, and nylon, all were within consumers' easy reach. Indeed, synthetic textiles became inexpensive enough to eventually capture half of the entire fiber market. All credit was owed to the ready feedstock supplies.