This Day in History (28-Feb-1935) – Wallace Carothers invents nylon at the DuPont Experimental Station near Wilmington, Delaware

In 1928, the DuPont chemical company opened a research laboratory for the development of artificial materials, deciding that basic research was the way to go – not a common path for a company to follow at the time. A basic lack of knowledge of polymer molecules existed when Wallace Carothers began his work there. Wallace and his team were the first to investigate the acetylene family. In 1931, the research team at DuPont turned their efforts towards a synthetic fiber that could replace silk. Japan was the United States’ main source of silk, and trade relations between the two countries were breaking apart.

By 1934, Wallace had made significant steps toward creating a synthetic silk. He created a new fiber formed by the polymerizing process and known as a condensation reaction. Wallace refined the process by adjusting the equipment so that the water was distilled and removed from the process making for stronger fibers. In 1935, DuPont patented the new fiber known as nylon. Nylon, the miracle fiber, was introduced to the world in 1938. Fortune Magazine  reported it as the first completely new synthetic fiber made by man. It further stated that “In over four thousand years, textiles have seen only three basic developments mercerized cotton, synthetic dyes and rayon. Nylon is a fourth.” Nylon was first used for fishing line, surgical sutures, and toothbrush bristles. DuPont touted its new fiber as being “as strong as steel, as fine as a spider’s web,” and first demonstrated nylon stockings not to a scientific society, but to the three thousand women’s club members  at the 1939 New York World’s Fair. In 1942, nylon went to war in the form of parachutes and tents. Nylon stockings were the favorite gift of American soldiers to impress British women. Today, nylon is still used in all types of apparel and is the second most used synthetic fiber. The company purposefully did not register “nylon” as a trademark – choosing to allow the word to enter the American vocabulary as a synonym for “stockings.”

Wallace Carothers can be considered the father of the science of man-made polymers and the man responsible for the invention of nylon and neoprene. The man was a brilliant chemist, inventor and scholar. Despite an amazing career, and holding more than fifty patents; the inventor ended his own life in depression.



This Day in History (24-Feb-1938) – Du Pont begins commercial production of nylon toothbrush bristles

Toothbrushing tools date back to 3500-3000 BC when the Babylonians and the Egyptians made a brush by fraying the end of a twig. Tombs of the ancient Egyptians have been found containing toothsticks alongside their owners. Around 1600BC, the Chinese developed “chewing sticks” which were made from aromatic tree twigs to freshen breath. The Chinese are believed to have invented the first natural bristle toothbrush made from the bristles from pigs’ necks in the 15th century, with the bristles attached to a bone or bamboo handle. When it was brought from China to Europe, this design was adapted and often used softer horsehairs which many Europeans preferred. The first toothbrush of a more modern design was made by William Addis in England around 1780 – the handle was carved from cattle bone and the brush portion was still made from swine bristles. In 1844, the first 3-row bristle brush was designed.

The world’s first synthetic fiber – nylon – was discovered in 1935, by a former Harvard professor  Wallace Carothers  working at a DuPont Corporation research laboratory. Later called Nylon 6 by scientists, the revolutionary product comes from chemicals found in petroleum. Interestingly, the first commercial use of revolutionary petroleum product “Nylon” was for toothbrushes, before Nylon became synonym for stockings. On February 24, 1938, the Weco Products Company of Chicago, Illinois, began selling its new “Dr. West’s Miracle-Tuft” – the earliest toothbrush to use synthetic DuPont nylon bristles.

“Until now, all good toothbrushes were made with animal bristles,” noted a 1938 Weco Products advertisement in Life magazine. “Today, Dr. West’s new Miracle-Tuft is a single exception. It is made with EXTON, a unique bristle-like filament developed by the great DuPont laboratories, and produced exclusively for Dr. West’s.” Johnson & Johnson of New Brunswick, New Jersey, introduced a competing nylon-bristle toothbrush in 1939.

Interestingly, we’ve been using the same material since the 1938. And we’ve been using the same overall design since the 1780s.



This Day in History (20-Oct-1950) – Chemists Archer John Porter Martin gives the first demonstration of gas chromatography

Archer John Porter Martin grew up in London, England, and from an early age demonstrated an aptitude for chemistry. As a child, he designed and built an apparatus for distillation from old coffee tins packed with charcoal, some as tall as five feet. He entered Cambridge University with the intention of pursuing a degree in chemical engineering. However, he was influenced by J. B. S. Haldane to specialize in biochemistry. At Cambridge his childhood experience with fractional distillation became valuable.

Very few chemical reactions produce clean, pure products with no trace of starting materials or impurities. Most generate a mixture whose individual components must be purified before the results can be identified. In the nineteenth and early twentieth centuries, purification of a chemical reaction product often required repetitive crystallizations, distillation, or solvent extraction.

Martin continued with his explorations of multi phase separation technology and went to work as a research chemist for the Wool Industries Research Association in Leeds. It was there that he met Richard Lawrence Millington Synge and began to collaborate with Synge on the problem of separating acetylamino acids. Eventually, Martin and Synge came up with the idea that, instead of using a counterflow extraction process with solvents moving against one another, they could partition one phase (hold one phase stationary using an appropriate support). The result was the invention of liquid-liquid partition chromatography, first reported in the Biochemistry Journal in 1941.

In their landmark paper, Martin and Synge also indicated that partition chromatography that used a carrier gas as the mobile phase was possible. Martin and Synge were awarded Nobel prize in Chemistry in 1952. Today, gas-liquid chromatography is probably the single most widely used analytical tool in chemistry.



This Day in History (22-May-1892) – Dr Washington Sheffield invents toothpaste tube

Toothpaste was used as long ago as 500 BC in both China and India; however, modern toothpastes were developed in the 1800s. In 1824, a dentist named Peabody was the first person to add soap to toothpaste. John Harris first added chalk as an ingredient to toothpaste in the 1850s. In 1873, Colgate mass-produced the first toothpaste in a jar.

In the late 19th century, numerous companies flooded the toothpaste market with products available in a variety of different jars—into which all members of a family might dip their brushes. Dr. Washington Sheffield, a dental graduate, formed a company for oral care products in New London, USA. During this time, Washington Sheffield’s son, Dr. Lucius Tracy Sheffield was in Paris, France, where he noticed artists using collapsible metal tubes for paints and inks. He thought putting the jar-packaged dentifrice in these tubes would be a good idea. Lucius communicated his observations to his father and shortly after, in 1892, Washington Sheffield unveiled first toothpaste tube. Sheffield’s toothpaste was called Dr. Sheffield’s Creme Dentifrice.

Taking all manner of manufacture under his own control, Dr. Sheffield began producing tubes made out of tin. He built facilities for printing and embossing the tubes and even manufactured the boxes for shipping them. In 1896, Colgate Dental Cream was packaged in collapsible tubes imitating Sheffield. The product was called Colgate Ribbon Dental Creme. Sheffield’s two grandsons took this idea a step further when they formed the New England Collapsible Tube Company in 1911—an enterprise that became the largest producer of collapsible tubes in the country. The company Washington Sheffield started is still in business today under the name Sheffield Pharmaceuticals. Still located on Broad Street in New London, it is in the business of making creams, ointments, and pastes for the medical and dental fields. In addition, it still makes its own formula of toothpaste.



This Day in History (7-Apr-1827) – English chemist John Walker invents wooden matches

JohnWalker, after schooling at Stockton-on-Tees  served a local doctor for a while as an assistant-surgeon, before finding out that he cannot accustom himself to the sight of blood and surgical operations. However, time spent as assistant-surgeon brought him closer to chemistry, which pushed him to study that subject at Durham and York. After spending several years learning pharmacy and apprenticing as wholesale druggists, he returned home and opened his own shop as “chemist and druggist”. He was one of the rare pharmacists in town who worked not only with natural ingredients, but also with many chemical substances which were not used much in human or animal medicine back then.

Experimenting with various chemical elements finally bore fruits when he discovered that cardboard strips dipped in a mixture of potassium chloride and stibnite and then allowed to dry would ignite when scraped rapidly against sandpaper.  This breakthrough led him to create first simple prototypes of matches which were made from cardboard sticks. By 1827 he started selling those matches what were called “friction lights”, and came to be called “lucifers” in slang, who instantly became very popular in his home town. By changing the design of the sticks into three inch long wooden splints, he soon received offers of purchase from neighboring towns and started selling more and more. Sadly, his design was not perfect, and because of that he never wanted to patent it. Sulfur on the head of the stick sometimes burned so brightly and hotly, that it managed to detach itself and fall on the floor, damaging either carpet or even clothes of the people who were wielding the match.

Since he did not obtain a patent, Walker received neither fame nor wealth for his invention of the now-common match. Sir Isaac Holden was widely credited with inventing the match until both Holden and Walker were dead, but the original ledger from Walker’s shop was subsequently found, which shows that Walker was selling his matches for at least two years before Holden began making matches of a similar chemical compound. The invention managed to create first version of items that would spread across entire world and change the way we look at the fire.



This Day in History (6-Mar-1869) – Dmitri Mendeleev presents the first periodic table to the Russian Chemical Society

Dmitry Mendeleyev, a master’s degree holder in chemistry was a teacher. He won an award to go to Germany to pursue chemical research where he attended a conference. This conference played a key role in Mendeleev’s eventual development of the periodic table. He watched as the conference produced an agreed, standardized method for determining atomic weights of elements. On his return to Russia, he realized that improved Russian language chemistry textbooks were a necessity. In just 61 days the 27 year old chemist poured out his knowledge in a 500 page textbook: Organic Chemistry. This book won the Domidov Prize and put Mendeleev at the forefront of Russian chemical education.

Chemistry was a patchwork of observations and discoveries then. In order to streamline, Mendeleev wrote the names of the 65 known elements on cards – much like playing cards – one element on each card. He then wrote the fundamental properties of every element on its own card, including atomic weight. He saw that atomic weight was important in some way – the behavior of the elements seemed to repeat as their atomic weights increased – but he could not see the pattern. Mendeleev moved the cards about for hour after hour until finally he fell asleep at his desk. When he awoke, he found that his subconscious mind had done his work for him! He knew the pattern the elements followed.

Mendeleyev found that, when all the known chemical elements were arranged in order of increasing atomic weight, the resulting table displayed a recurring pattern, or periodicity, of properties within groups of elements.  Mendeleyev discovered the periodic law. His newly formulated law was announced before the Russian Chemical Society in March 1869 with the statement “elements arranged according to the value of their atomic weights present a clear periodicity of properties.”  In his version of the periodic table of 1871 of known 70 elements, he left gaps in places where he believed unknown elements would find their place. He even predicted the likely properties of three of the potential elements. The subsequent proof of many of his predictions within his lifetime brought fame to Mendeleyev as the founder of the periodic law.



This Day in History (1-Mar-1896) – Henri Becquerel discovers radioactivity

Antoine Henri Becquerel, a French scientist, was conducting an experiment in Feb 1896, which started with the exposure of a uranium-bearing crystal to sunlight. Once the crystal had sat in the sunshine for a while, he placed it on a photographic plate. As he had anticipated, the crystal produced its image on the plate. Becquerel theorized that the absorbed energy of the sun was being released by the uranium in the form of x-rays. Further testing of this theory had to be put off for a few days because the sky had clouded up and the sun had disappeared. For the next couple of days he left his sample of uranium in a closed drawer along with the photographic plate. When the weather had cleared on March 1st, he returned to the drawer to retrieve his gear. He was surprised to find that the crystal had left a clear, strong image on the photographic plate.

How could this be? There was no source of energy to produce the image! What Becquerel had discovered was that a piece of mineral which contained uranium could produce it’s image on a photographic plate in the absence of light. He attributed this phenomenon to spontaneous emission by the uranium. The phenomenon was found to be common to all the uranium salts studied and was concluded to be a property of the uranium atom. Later, Becquerel showed that the rays emitted by uranium, which for a long time were named after their discoverer, caused gases to ionize and that they differed from X-rays in that they could be deflected by electric or magnetic fields. As the new radiation was bent by the magnetic field so that the radiation must be charged and different than x-rays. When different radioactive substances were put in the magnetic field, they deflected in different directions or not at all, showing that there were three classes of radioactivity: negative, positive, and electrically neutral.

Although Becquerel did not pursue these findings, Pierre Curie and Marie Curie researched further and came up with the term “radioactivity”. For his discovery of spontaneous radioactivity Becquerel was awarded half of the Nobel Prize for Physics in 1903, the   other half being given to Pierre and Marie Curie for their study of the Becquerel radiation.