But Stine proposed what he called "a radical departure from previous policy" — a program of "pure science" with "the object of establishing or discovering new scientific facts" without obvious practical applications. Stine argued that DuPont's support of work in pure science would enhance the company's prestige, make recruiting Ph.
Finally, he added, something of practical value might come out of it. Stine chose five lines of study — colloid chemistry, catalysis, the generation of chemical and physical data, organic synthesis, and polymerization — and set out to recruit the very best chemists to head each field. In , he persuaded Wallace H. Carothers, a brilliant young instructor in organic chemistry at Harvard University, to head the program in organic synthesis.
Wallace Carothers was born in Burlington, Iowa, on April 27, , the son of Presbyterians of modest means. In he enrolled at Tarkio College, a small Presbyterian-supported school in northwestern Missouri. There he majored in chemistry while helping in the school's floundering commercial department.
When the chemist who ran the college's one-man science department departed in , Carothers, then a senior, took over the college's chemistry classes.
After graduating from Tarkio in , Carothers continued his studies at the University of Illinois , at the time the preeminent school in the United States for training organic chemists. There, he earned a Master's degree in and a Ph. Years later, Adams characterized Carothers as "the best organic chemist in the country. While an instructor at Illinois, Carothers became interested in the electronic theory of valence to explain how atoms in organic molecules bond together.
It was a theory propounded by the physical chemist G. Lewis of the University of California at Berkeley. But most organic chemists of the time ignored that theory, if they did not dismiss it outright. Carothers published a paper on the electronic nature of the carbon-carbon double bond in the Journal of the American Chemical Society in It marked his growing interest in theoretical as well as experimental organic chemistry.
In , Carothers accepted a teaching post in organic chemistry at Harvard University, but he was uncomfortable as a classroom lecturer. When DuPont offered Carothers the opportunity to do fundamental research, at first he was reluctant to accept.
He agreed to do so once convinced that he would be free to work on whatever interested him and that he would command an ample budget for supplies and equipment. Stine also provided Carothers with a staff of newly minted Ph. Shortly after arriving at the newly constructed laboratory later dubbed "Purity Hall" on February 6, , Carothers began to study the structure and synthesis of polymers.
He concluded from the literature that long molecules could be strung together from small organic compounds that had a reactive functional group at each end.
He called these resulting products "condensation polymers" because another compound such as water would be split off as a byproduct. Carothers and a small group of young Ph. This reaction, known as esterfication, was roughly akin to linking together a chain of paper clips.
The resulting long chain molecules were polyesters. Progress was rapid, and the resulting polymers theoretically interesting. But their molecular weights were 4, or less. Carothers was aiming for larger molecules. He concluded that the water formed during the esterfication reaction was limiting the chain length. Meanwhile, in Carothers had been asked by Elmer Bolton, the new head of DuPont's chemical department, to look into polymers based on acetylene.
Unlike Stine, who emphasized pure science, Bolton believed that research should be aimed at clearly defined applications. The freewheeling days of fundamental research at DuPont were fading.
Bolton, who previously had headed DuPont's research on dyes, had long been interested in producing a synthetic rubber. In the late s he had followed the research of Father Julius Nieuwland of Notre Dame University, who used a cuprous chloride catalyst to combine two or three acetylenes into mono- or divinylactetylene. Bolton realized that these compounds were similar to isoprene, the molecule that is the basic structural unit of natural rubber.
Carothers assigned Arnold Collins to make a very pure sample of divinylacetylene. While distilling the products of the acetylene reaction in March , Collins obtained a small amount of an unknown liquid, which he put aside in stoppered test tubes. A few days later he found that the liquid had congealed into a clear homogenous mass. When Collins dislodged the mass from its container, it bounced. Analysis showed that the mass was a polymer of chloroprene, formed with chlorine from the cuprous chloride catalyst.
Accidentally, Collins had prepared a new synthetic rubber. DuPont began large-scale production of polychloroprene, marketed under the name Duprene later changed to neoprene , in Neoprene was difficult and expensive to manufacture, however, and it didn't really rival natural rubber, which was selling for only a few cents per pound in the early s.
Neoprene — which was resistant to weather, oil, chemicals, and heat — found several relatively small but profitable uses. After Stine hired him, Carothers decided to concentrate on polymers, those giant molecules that are the building blocks of such familiar substances as rubber and cotton.
But Bolton encouraged him not to give up on the wider field of fibers. When Carothers finally renewed work in that area in early , he and his team used amines rather than glycols to produce polyamides rather than polyesters. Polyamides are synthetic proteins and are more stable than polyesters, which are structurally similar to natural fats and oils. Bolton played a key role in the development of the discovery, later named nylon.
By this time Bolton had decided to commercialize nylon, setting his sights first on capturing the lucrative silk-stocking market with alternative products made from the synthetic fiber. Jack loved the ocean and spent every opportunity down at Ocean Beach bodysurfing in bathing trunks in the briny cold water. The story goes that Jack began experimenting with different materials that would prevent him from, quite literally, freezing his balls off.
He experimented with PVC stuffed into his trunks, but it wasn't until his bodysurfing friend, Harry Hind, showed Jack a sample of neoprene foam that his first wetsuit-type vests emerged. Hind knew that neoprene was an insulating material thanks to his own laboratory work.
After experimenting with neoprene and finding it superior to other insulating foams, Jack founded the wetsuit manufacturing company 'O'Neill' in a garage in , later relocating to Santa Cruz, California in with the motto "It's Always Summer on the Inside".
Bob and Bill Meistrell, from Manhattan Beach, California, also started experimenting with neoprene around They started a company which would later be named Body Glove. However neoprene was not the only material used in early wetsuits, particularly in Europe.
The Heinke Dolphin Suit of the same period, also made in England, came in a green male and a white female version, both manufactured from natural rubber lined with stockinet. The modern wetsuit is perfected Originally, neoprene wetsuits were made with raw sheets of foam-rubber that did not have any backing material. This type of suit required extra caution while pulling it on because the raw foam-rubber by itself is both fragile and sticky against bare skin.
Stretching and pulling excessively easily caused these suits to be torn in half. This was somewhat remedied by thoroughly powdering the suit and the body with talc to help the rubber slide on more easily, but it was far from ideal. During the early '60s everybody was "goin' surfing" and many needed wetsuits to do it.
The problem of how to keep the neoprene from tearing and how to make wetsuits easier to slip on and off was solved with one simple solution: laminating elastic nylon jersey to the surface of the neoprene. Using nylon as a backing material to strengthen the neoprene, combined with the introduction of the zig-zag stitch, was a huge leap forward. New kids on the block: Yamamoto Corporation During the s a new type of neoprene was pioneered.
Up until this time, the process of manufacturing neoprene involved petroleum and petro-chemicals. The chloroprene rubber chips needed for the first stage of production were produced during the polymerization process by heating oil which we are currently running out of worldwide to extremely high temperatures. Yamamoto Corporation developed special technology to convert the calcium carbonate from limestone into chloroprene rubber chips and then further processing to achieve neoprene foam with a very high micro-cell structure.
This new process results in neoprene with very different characteristics to oil based neoprene. Nevertheless, a breakthrough was on the horizon. In , chemists at E. Du Pont de Nemours discovered the elastomer known as neoprene. Of the more than twenty chemists who helped to make this discovery possible, four stand out: Elmer Bolton, Julius Nieuwland, Wallace Carothers, and Arnold Collins.
Largely because of the rapidly increasing price of rubber, he initiated a project to synthesize an elastomer from acetylene, a gaseous hydrocarbon. The presenter was Julius Nieuwland, the foremost authority on the chemistry of acetylene.
Nieuwland was a professor of organic chemistry at the University of Notre Dame. One of his students was the legendary football coach Knute Rockne. The priest-scientist had been investigating acetylene reactions for more than twenty years. Using a copper chloride catalyst he had discovered, he isolated a new compound, divinylacetylene DVA. He later treated DVA with a vulcanizing hardening agent and succeeded in producing a rubberlike substance, but the substance proved to be too soft for practical use.
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