The Curious History of PEX

Published: March 9, 2021 - by Dan Holohan

If a shoe factory had been present in Thomas Engel’s vicinity at the time he invented PEX, we would perhaps today be walking around on shoe soles made of cross-linked polyethylene. In this episode, Dan Holohan shares the fascinating story behind PEX and its brilliant inventor.

 

Episode Transcript

When I met Thomas Engel in Sweden on November 28, 1990, he said, "The paths of life are frequently this strange."

He said this after mentioning that if a shoe factory had been present in his vicinity at the time he invented PEX, we would perhaps today be walking around on shoe soles made of cross-linked polyethylene.

But it was chickens, not shoes, that put PEX on the map. "In our neighborhood,” he explained, “there was a chicken farm, and one day I was asked whether I could make pipes of this material, which could be laid in the ground. In this way, the hens would have a larger amount of heat and would lay more eggs."

Chickens. Gosh.

"In 1965,” he continued, “I was together with various scientists of the Phillips Petroleum Company in Bartlesville, Oklahoma, and we were discussing the cross-linking of polyethylene. It was possible at that time to cross-link polyethylene by means of highly active radiation. The problem, however, lay not only in the extremely expensive, and somewhat dangerous, equipment, but also because this method of cross-linking was feasible only for wall thicknesses of up to 0.5 mm. The important uses for cross-linking polyethylene would, however, always be for thick-walled parts, having a wall thickness of one to 10 mm.


"I began my studies using an extruder and I very rapidly found that this technique was not feasible. This was followed by lengthy experiments with laser beams. Finally, I decided in favor of a compression method, with intermolecular friction, telling myself that the cross-linking of the molecules would have to be easier if I could heat them rapidly and bring them closer together by high pressure, so as to then cross-link them in the presence of a catalyst. Years of intensive research followed, finally culminating in success. The result was a handful of glittering white plastic, which came out of the autoclave.

"With this small treasure in my pocket, I flew back to Phillips Petroleum in the U.S., where we carried out analysis. We found I had actually obtained 97% cross-linking. And as a result, the thread-shaped chains of molecules connected directly to each other. We heated the polyethylene and the plastic simply would no longer melt into a shapeless mass. The joy was immense, but what was to be done with this new plastic, and into what could it be fabricated?"

He then explained how he traveled from one chemical company to another in the hope of selling a license, but the answer was always the same: "That's marvelous, but what do we do with it?"

Enter the chickens, just strolling down the path of life. They led Thomas Engel to Wirsbo (which is now Uponor), and to the laying of pipe under the turf of Olympia Stadium in Munich for the 1972 Summer Olympics (another first).

The first OPEC oil embargo followed in 1973, and we began looking at low-temperature, hydronic radiant heating as a way to save energy.

Thomas Engel had no advanced degrees. In fact, he never finished high school. At 19, he walked out of the American POW camp at Ingolstadt, Bavaria. He worked as a dishwasher, drove a taxi, labored in a furniture factory and in construction. And then he began to experiment with polyethylene, which he had read about during his years as a prisoner of war in American magazines. That led to his invention of Engel-method PEX. He went on to get 120 patents, but preferred selling rights or licenses to his inventions rather than become a manufacturer. He was a millionaire before he was 30 years old.

His licensee in the U.K. during the early-1950s was a collector of A.L. BreGeh timepieces. Brequet died in 1823, and many consider him to be the finest watchmaker of all time. Thomas Engel was so taken by BreGeh's art that he became a collector himself and went on to write the book, A.L. BreGeh, Watchmaker to Kings, Thoughts on Time. He also made incredible watches of his own design, some of which have sold at Christie's for more than I paid for my car.

And you may think that inventing PEX and building beautiful timepieces would be enough for one life, right? Especially coming from a guy who had no formal education and spent much of his teen years in an American POW camp. But that wasn’t enough for Thomas Engel.

I came across an article from November, 2013 announcing that Thomas Engel had just announced that he had solved the permanent-magnet motor puzzle and wanted to give away his discovery because mankind needs affordable energy. His motor is spinning in Lucerne, Switzerland to this day.

Lukas Weber, the article's author, wrote "During the three hours we were there, his motor was chugging along quietly. There is no noticeable development of heat. The motor obtains its power from neo-DIM-e-um magnets. Those are the strongest permanent magnets known. Neo-DIM-e-um is a rare-earth element, much used in electronics.

"Engel's idea is that it should be possible to convert that power of the magnets into rotary motion. He built a machine made of brass, resembling a miniature lathe. The rotor is a disc with magnets fixed to it. The shaft turns in ceramic bearings. A disc magnet fixed at the correct angle and distance from the rotor, but which itself is able to rotate (Engel calls it the mirror) can affect the rotor magnets. There is attractive and repulsive force, depending on the orientation of the pole. The rotor can be set in continuous motion, as long as the mirror keeps rotating. The mirror's rotation regulates the speed of the rotor. The mirror hangs in a kind of outrigger. Two electric wires connect to the lower end with crocodile clips. There is a tiny electric motor that rotates the mirror. So it isn't possible to do this without electricity altogether? 'No,' Engel says, 'It needs only eight milliamperes at nine volts.' This is only a control mechanism. The power at the shaft is much greater.

"The rotation is about 400 RPM. It is difficult to stop the rotation by grabbing the shaft. The output felt at the shaft is clearly greater than the input needed to give the impulse. Of course, measurement was only done with human sensors. Mr. Engel would like to do more experimentation with the number of magnets and their form, but he says he lacks the strength for further development.

"The inventor's reaction to the question of whether his motor is a perpetual motion machine is somewhat resentful. 'There is no such thing,' he says. Mr. Engel is convinced that his machine uses the enormous energy which is inherent in quanta, those inconceivably small components of atoms first described by the physicist, Max Planck, in the early part of the last century. He therefore calls his machine a quantum-deviation apparatus. Some things are still unclear for the inventor himself. He says it has to be further developed, and he next wants to attach a small generator to the shaft and show that his motor delivers more electricity than is needed for its control. If he could do that, we'd really have some sensational news."

The paths of life are frequently strange, and brilliant people are often seen as somewhat crazy at first. But they're also often right.

Thomas Engel came to the end of life's path in April 2015. He was 88 years old, and I feel blessed for having been able to spend a few hours with that remarkable man. And although he’s gone, his motor continues to spin. It is now up to others to figure out why. And how. And isn’t life delicious?

If you liked this tale, please share it with others. And if you haven’t already, please subscribe to this podcast. I have many more Dead Men Tales for you. Thanks for spending some time with me. I appreciate you.