Nearly everything is fine in moderation. Plastics exploded as an industry in the post World War II boom of the 50s and on - but goes back far further. A plastic is a category of materials called a polymer. These are materials comprised of long chains of molecules that can be easily found in nature because cellulose, the cellular walls of plants, comes in many forms. But while the word plastics comes from easily pliable materials, we don’t usually think of plant-based products as plastics. Instead, we think of the synthetic polymers.
But documented uses go back thousands of years, especially with early uses of natural rubbers, milk proteins, gums, and shellacs. But as we rounded the corner into the mid-1800s with the rise of chemistry things picked up steam. That’s when Charles Goodyear wanted to keep tires from popping and so discovered vulcanization as a means to treat rubber. Vulcanization is when rubber is heated and mixed with other chemicals like sulphur.
Then in 1869 John Wesley Hyatt looked for an alternative to natural ivory for things like billiards. He found that cotton fibers could be treated with camphor, which came from the waxy wood of camphor laurels. The substance could be shaped, dried, and then come off as most anything nature produced. When Wesley innovated plastics most camphor was extracted from trees, but today most camphor is synthetically produced from petroleum-based products, further freeing humans from needing natural materials to produce goods. Not only could we skip killing elephants but we could avoid chopping down forests to meet our needs for goods.
Leo Baekeland gave us Bakelite in 1907. By then we were using other materials and the hunt was on for all kinds of materials. Shellac had been used as a moisture sealant for centuries and came from the female lac bugs in trees around India but could also be used to insulate electrical components. Baekeland created a phenol and formaldehyde solution he called Novolak but as with the advent of steel realized that he could change the temperature and how much pressure was applied to the solution that he could make it harder and more moldable - thus Bakelite became the first fully synthetic polymer.
Hermann Staudinger started doing more of the academic research to explain why these reactions were happening. In 1920, he wrote a paper that looked at rubber, starch, and other polymers, explaining how their long chains of molecular units were linked by covalent bonds. Thus their high molecular weights. He would go on to collaborate with his wife Magda Voita, who was a bonanist and his polymer theories proven. And so plastics went from experimentation to science.
Scientists and experimenters alike continued to investigate uses and by 1925 there was even a magazine called Plastics. They could add filler to Bakelite and create colored plastics for all kinds of uses and started molding jewelry, gears, and other trinkets. They could heat it to 300 degrees and then inject it into molds. And so plastic manufacturing was born. As with many of the things we interact with in our modern world, use grew through the decades and there were other industries that started to merge, evolve, and diverge.
Éleuthère Irénée du Pont had worked with gunpowder in France and his family immigrated to the United States after the French Revolution. He’d worked with chemist Antoine Lavoisier while a student and started producing gunpowder in the early 1800s. That company, which evolved into the modern DuPont, always excelled in various materials sciences and through the 1920s also focused on a number of polymers. One of their employees, Wallace Carothers, invented neoprene and so gave us our first super polymer in 1928. He would go on to invent nylon as a synthetic form of silk in 1935. DuPont also brought us Teflon and insecticides in 1935.
Acrylic acid went back to the mid-1800s but as people were experimenting with combining chemicals around the same time we saw British chemists John Crawford and Rowland Hill and independently German Otto Röhm develop products based on polymathy methacrylate. Here, they were creating clear, hard plastic to be used like glass. The Brits called theirs Perspex and the Germans called theirs Plexiglas when they went to market, with our friends back at DuPont creating yet another called Lucite.
The period between World War I and World War II saw advancements in nearly every science - from mechanical computing to early electrical switching and of course, plastics. The Great Depression saw a slow-down in the advancements but World War II and some of the basic research happening around the world caused an explosion as governments dumped money into build-ups. That’s when DuPont cranked out parachutes and tires and even got involved in building the Savannah Hanford plutonium plant as a part of the Manhattan Project. This took them away from things like nylon, which led to riots. We were clearly in the era of synthetics used in clothing.
Leading up to the war and beyond, every supply chain of natural goods got constrained. And so synthetic replacements for these were being heavily researched and new uses were being discovered all over the place. Add in assembly lines and we were pumping out things to bring joy or improve lives at a constant clip. BASF had been making dyes since the 1860s but chemicals are chemicals and had developed polystyrene in the 1930s and continued to grow and benefit from both licensing and developing other materials like Styropor insulating foam.
Dow Chemical had been founded in the 1800s by Herbert Henry Dow, but became an important part of the supply chain for the growing synthetics businesses, working with Corning to produce silicones and producing styrene and magnesium for light parts for aircraft. They too would help in nuclear developments, managing the Rocky Flats plutonium triggers plant and then napalm, Agent Orange, breast implants, plastic bottles, and anything else we could mix chemicals with. Expanded polystyrene led to plastics in cups, packaging, and anything else.
By the 60s we were fully in a synthetic world. A great quote from 1967’s “The Graduate” was “I want to say one word to you. Just one word. Are you listening? Plastics.” The future was here. And much of that future involved injection molding machines, now more and more common. Many a mainframe was encased in metal but with hard plastics we could build faceplates out of plastic. The IBM mainframes had lots of blinking lights recessed into holes in plastic with metal switches sticking out. Turns out people get shocked less when the whole thing isn’t metal.
The minicomputers were smaller but by the time of the PDP-11 there were plastic toggles and a plastic front on the chassis. The Altair 8800 ended up looking a lot like that, but bringing that technology to the hobbyist. By the time the personal computer started to go mainstream, the full case was made of injection molding.
The things that went inside computers were increasingly plastic as well. Going back to the early days of mechanical computing, gears were made out of metal. But tubes were often mounted on circuits screwed to wooden boards. Albert Hanson had worked on foil conductors that were laminated to insulating boards going back to 1903 but Charles Ducas patented electroplating circuit patterns in 1927 and Austrian Paul Eisler invented printed circuits for radio sets in the mid-1930s. John Sargrove then figured out he could spray metal onto plastic boards made of Bakelite in the late 1930s and uses expanded to proximity fuzes in World War II and then Motorola helped bring them into broader consumer electronics in the early 1950s.
Printed circuit boards then moved to screen printing metallic paint onto various surfaces and Harry Rubinstein patented printing components, which helped pave the way for integrated circuits. Board lamination and etching was added to the process and conductive inks used in the creation might be etched copper, plated substrates or even silver inks as are used in RFID tags. We’ve learned over time to make things easier and with more precise machinery we were able to build smaller and smaller boards, chips, and eventually 3d printed electronics - even the Circuit Scribe to draw circuits.
Doug Engelbart’s first mouse was wood but by the time Steve Jobs insisted they be mass produceable they’d been plastic for Englebart and then the Alto. Computer keyboards had evolved out of the flexowriter and so become plastic as well. Even the springs that caused keys to bounce back up eventually replaced with plastic and rubberized materials in different configurations.
Plastic is great for insulating electronics, they are poor conductors of heat, they’re light, they’re easy to mold, they’re hardy, synthetics require less than 5% of the oil we use, and they’re recyclable. Silicone, another polymer, is a term coined by the English chemist F.S. Kipping in 1901. His academic work while at University College, Nottingham would kickstart the synthetic rubber and silicone lubricant industries. But that’s not silicon. That’s an element and a tetravalent metalloid at that. Silicon was discovered in 1787 by Antoine Lavoisier. Yup the same guy that taught Du Pont. While William Shockley started off with germanium and silicon when he was inventing the transistor, it was Jack Kilby and Robert Noyce who realized how well it acted as an insulator or a semiconductor it ended up used in what we now think of as the microchip. But again, that’s not a plastic…
Plastic of course has its drawbacks. Especially since we don’t consume plastics in moderation. It takes 400 to a thousand years do decompose many plastics. The rampant use in every aspect of our lives has led to animals dying after eating plastic, or getting caught in islands of it as plastic is all over the oceans and other waterways around the world. That’s 5 and a quarter trillion pieces of plastic in the ocean that weighs a combined 270,000 tons with another 8 million pieces flowing in there each and every day. In short, the overuse of plastics is hurting our environment. Or at least our inability to control our rampant consumerism is leading to their overuse. They do melt at low temperatures, which can work as a good or bad thing. When they do, they can release hazardous fumes like PCBs and dioxins. Due to many of the chemical compounds they often rely on fossil fuels and so are derived from non-renewable resources. But they’re affordable and represent a trillion dollar industry. And we can all do better at recycling - which of course requires energy and those bonds break down over time so we can’t recycle forever. Oh and the byproducts from the creation of products is downright toxic.
We could argue that plastic is one of the most important discoveries in the history of humanity. That guy from The Graduate certainly would. We could argue it’s one of the worst. But we also just have to realize that our modern lives, and especially all those devices we carry around, wouldn’t be possible without plastics and other synthetic polymers. There’s a future where instead of running out to the store for certain items, we just 3d print them. Maybe we even make filament from printed materials we no longer need. The move to recyclable materials for packaging helps reduce the negative impacts of plastics. But so does just consuming less. Except devices. We obviously need the latest and greatest of each of those all the time!
Here’s the thing, half of plastics are single-purpose. Much of it is packaging like containers and wrappers. But can you imagine life without the 380 million tons of plastics the world produces a year? Just look around right now. Couldn’t tell you how many parts of this microphone, computer, and all the cables and adapters are made of it. How many couldn’t be made by anything else. There was a world without plastics for thousands of years of human civilization. We’ll look at one of those single-purpose plastic-heavy industries called fast food in an episode soon. But it’s not the plastics that are such a problem. It’s the wasteful rampant consumerism. When I take out my recycling I can’t help but think that what goes in the recycling versus compost versus garbage is as much a symbol of who I want to be as what I actually end up eating and relying on to live. And yet, I remain hopeful for the world in that these discoveries can actually end up bringing us back into harmony with the world around us without reverting to luddites and walking back all of these amazing developments like we see in the science fiction dystopian futures.