[Cardiff, Wales – 11:12 PM, 13/02/1920]
We had officially started production now, and for the last two months we had been producing about three tonnes a week.
The process starts with the creation of chloroprene, the monomer that forms the basic structure. The first thing we do is obtain the primary ingredient, Divinyl Ethylene, a chemical waste compound that comes from petroleum refining.
While Cardiff itself didn't have any fuel refineries, the Llandarcy Refinery, which was opened in 1921 by the Anglo-Persian Oil Company, used Cardiff for exports, so we had ample access to the feedstock for essentially nothing.
Carefully, we feed this into the reactor chamber, where we add chlorine gas under controlled conditions. The reaction happens at a high temperature and pressure, forming the chloroprene. Once the reaction is complete, we purify the chloroprene through distillation, removing any impurities to ensure that only pure chloroprene will move forward to the next step since before then it is an impure, odorous liquid, carrying traces of unreacted divinyl ethylene and various chlorinated by-products.
To purify it, we first allowed it to settle and then carefully washed it with cold water to remove soluble acids. Next, we employ fractional distillation under reduced pressure, carefully controlling the temperature to separate chloroprene from heavier or more volatile contaminants. Each fraction was tested, and only the pale-yellow, sharply pungent portion was retained. Finally, it's passed through a bed of finely powdered calcium chloride to remove any remaining moisture, yielding a clear, stable monomer suitable for polymerisation.
Handling at this stage required vigilance, for even a small lapse could lead to polymerisation in the chambers, leading to hours of cleanup. Yes, this happened multiple times.
Now comes the exciting part: polymerisation. This is where we transform the chloroprene into actual polymer chains that will make up the rubber. In our massive reactors, we mix the purified chloroprene with water, emulsifiers (sodium lauryl sulphate, potassium oleate, polyethylene glycol, cetyltrimethylammonium bromide, and stearic acid), and a free-radical initiator of hydrogen peroxide. The reaction takes place in an emulsion polymerisation process, which means it occurs in water rather than a solvent.
In the reactor, temperature and pressure are key. We have to monitor them closely because even small fluctuations can change the polymer's properties. I cursed not having digital ones but we made do. I did make them use metric, though, since it was better to learn now instead of switch over later.
As the reaction progresses, the monomers link up into long chains, creating a polychloroprene polymer. Depending on the desired properties, the polymerisation may take several hours, and we always make sure to control the speed of the reaction to get the right molecular weight.
Building a reliable reactor for the polymerisation of chloroprene presented significant challenges due to the limitations of technology and materials available. The process required precise control over temperature, pressure, and the introduction of chemicals like chlorine gas, all of which posed risks of instability, contamination, and explosion.
The reactors needed to withstand high pressures and corrosive chemicals, yet materials such as steel or cast iron are not sufficiently resistant to the harsh conditions inside the reactor.
Furthermore, the need for accurate mixing and temperature control in a consistent, scalable manner was difficult to achieve with the primitive thermometers, valves, and pumps available. We had to develop rudimentary but effective systems, often relying on trial and error, to ensure the polymerisation process could be safely and efficiently managed.
After polymerisation, I move the mixture into a precipitation tank. Here, we add calcium chloride to act as a coagulant, which causes the polychloroprene to separate from the water. Once we have the solid chloroprene particles, we carefully wash them again to remove any residual chemicals, unreacted monomers, and water. This is a crucial step because impurities can degrade the final product, and by using high-pressure water jets, we ensure the rubber is as clean as possible.
After washing, it's time for the neoprene to dry. In our drying system we use large rotary dryers, powered by steam, to evaporate the remaining water. It's critical not to overheat the material, as that can affect its quality. Once the neoprene is dry, it is fed into pelletisers or extruders. These machines cut the rubber into small pellets or uniform sheets, making it easier to handle.
In the future I'll start adding more additives to different batches at this stage to get different results, but for now it's fine. For example, you'd take the dry chloroprene and mix the rubber with various additives in various amounts for different uses, such as plasticisers (like diisononyl phthalate), stabilisers (like phenolic antioxidants), vulcanising agents (like sulphur), and antioxidants (like butylated hydroxytoluene). This is all loaded into a massive Banbury mixer, which is a powerful machine with rotating blades that blend the materials at high speeds and temperatures. The goal is to ensure that all the ingredients are thoroughly mixed and uniformly distributed throughout the rubber. Hopefully with practice we can adjust the formulation or specific characteristics like flexibility, hardness, and strength, but it would have to wait since I'm running out of money. For now the only thing added is sulphur.
Once the right consistency is achieved, the compounded rubber is then ready to move to the next stage.
At this point, the compounded chloroprene is put through vulcanisation, the process that crosslinks the polymer chains and gives the material its final strength and elasticity. I pass the neoprene through the large extrusion ovens, where it is heated to temperature, typically between 140°C and 200°C. The heat causes the sulphur to form cross-links between the polymer chains, which makes the material more durable and gives it the desired properties. After curing, we make sure to cool the neoprene at a controlled rate to lock in its new structure.
Once the neoprene has been vulcanised, it's put through a post-curing stage in an autoclave or drying oven. This ensures that any remaining volatile compounds are removed and that the rubber achieves maximum stability and consistency. At this point, we begin quality control. Our team uses set systems which we're still refining to test various aspects of the neoprene, including its tensile strength, elongation at break, hardness, tear resistance, and chemical resistance. Samples are run through these tests to make sure that the neoprene meets the standards for the specific applications it will be used for.
After quality control, the neoprene is finally made and is ready for the final processing stage. If we are making sheets, the neoprene is cut into large rolls and coiled, ready for transport. We were currently fulfilling an order for 20 tonnes from the government, and Arthur had told me that if things continued as they were, we should have enough money to survive until they paid us.
I smiled, holding a small black rubber ball in my hand, before I went back to mindlessly bouncing it against the wall while I wrote down chemical formulas on a chalkboard in one of the offices I had converted to a basic chemistry lab. I couldn't help but giggle slightly since it was the first batch that had no input from me, entirely relying on the staff and Arthur to run the factory.
The fact that most of the chemicals that were needed had to be made in-house and the main materials were all waste products meant it was fairly cheap, not that I'd be telling the government that.
Of course some of our initial batches had to be chucked since they came out bad, but until I could make higher-quality equipment and machines, it was only to be expected.
One of the workers had shaped a small ball of the stuff, and soon enough it was being thrown around the factory. One of the managers had to stop that after someone tripped, but it had given me the idea to just make thousands of bouncy balls and ship them to toy shops across the country for free to entice them to buy more in the future.
Of course, once the patents were approved.
[Exmouth, England - 9:42 AM 27/02/1920]
"Come on, let's see it then," said an older man sitting next to me in a pub. I had written him in an attempt to get his endorsement and had piqued his interest. Well, that wasn't the primary, though. The actual reason was because he was someone I'd read about and wanted to meet before he died.
His name was Henry Wickman. He was an explorer and planter who is best known for his role in the introduction of rubber trees to the British colonies in Southeast Asia, a move that had a profound impact on the global rubber industry.
You see, in the 1870s Brazil had a complete monopoly on rubber, so he snuck into the Amazonian river basin, stole the seeds, and brought them to Ceylon and Malaya, where industrial planting began. Wickham's actions were controversial, as they were seen as a form of industrial espionage, but they also contributed significantly to the development of the global rubber industry; he also has hundreds of connections throughout the industry.
He faced financial difficulties in his later years and spent much of his time in relative obscurity, living in Exmouth until his death a few years from now.
Wickman spent a few moments appraising the material and then said, "Son, how in God's name did you do this?"
"Eh, I was messing around with synthetic polymers from oil runoff; it solidified, and it was kind of like rubber, so I spent a few months on it, patented it, and then spent a few months setting up a plant to make it by the tonne."
I lied.
"It's less elastic," he said, trying to stretch it.
I shrugged. "I'm aware, but it's more durable, barely reacts with chemicals or sunlight, and is more consistent. I'm willing to give you 5% of licensing fees if you would be willing to endorse it, though only if you think it would be appropriate. I would never force a man to lie."
I totally would, actually.
He waved me off as he took another drink and said, "Your product speaks for itself. I'll write to a few friends, and they can come see for themselves at your factory."
"What was it like in Brazil? "I asked, genuinely curious.
He sat straighter at that, as a glazed look overcame him. "Ah, Brazil. So beautiful, and yet not for the faint of heart! The jungle, the rivers, the heat…it all stays with you. And yes, I came close to getting caught…"
"...more than once. Those rubber barons didn't take kindly to a foreigner poking about. Smuggling those seeds out was like playing cat and mouse with the devil himself, and I never told anyone, but just outside Manaus I spent days evading both jaguars and search parties while my 'samples' were tucked safely under a false bottom in my luggage. Ah, those were the days. Shame I caught malaria, though; I barely survived, and my constitution was just never the same again. Thankfully I never caught it while in the Orient."
I was enthralled as he told me about dozens of experiences he had endured both in the wild and in the eccentricities of British politics. The latter of which he seemed far more terrified of.
I then said, "I wish to fund an expedition into a remote part of Tanganyika in the next few months from now. Would it be possible for you to help me find some experts? I would pay them handsomely, of course."
"I like you, lad; I'll see what I can do." He said, as we shook hands.
Honestly, meeting one of those national legends was kind of awe-inspiring, even if, unfortunately, most by the modern day had never heard of the man.
Over the next few weeks I was in constant meetings with businessmen negotiating deals. By May I was physically exhausted, but it had paid off. Dozens of chemical companies were clamouring for licensing deals from across Europe, Japan and the US. One industry that had almost immediately glanced at the material was tyres. Until now they were made of natural rubber, were insanely expensive, and only lasted a short while.
I was hesitant to license out technologies but decided it was fine for rubber since both Japan and Germany would have their own synthetic rubber production by WW2 anyway, whether I hid it or not, and the main limiting factor wasn't maturity but feedstock, and oil was something both Japan and Germany had access issues with.