On this day in science history: the first U.S. patent for a liquid soap was issued

In 1865, the first U.S. patent for a liquid soap was issued to William Sheppard of New York City (No. 49,561). The patent described his "discovery that by the addition of comparatively small quantities of common soap to a large quantity of spirits of ammonia or hartshorn is thickened to the consistency of molasses, and a liquid soap is obtained of superior detergent qualities." The proportions given were to dissolve one pound of common soap in water or steam, and then add 100-lbs of ammonia such that the liquid thickens to the consistency of molasses. The product was expected to be useful for both domestic and manufacturing purposes. (Hartshorn is an ancient name for an aqueous solution of ammonia).

Decorative soaps, by Phanton at English Wikipedia (Transferred from en.wikipedia to Commons.) [Public domain], via Wikimedia Commons

So, how does soap clean?

Action of soap

When used for cleaning, soap allows insoluble particles to become soluble in water, so they can then be rinsed away. For example: oil/fat is insoluble in water, but when a couple of drops of dish soap are added to the mixture, the oil/fat dissolves in the water. The insoluble oil/fat molecules become associated inside micelles, tiny spheres formed from soap molecules with polar hydrophilic (water-attracting) groups on the outside and encasing a lipophilic (fat-attracting) pocket, which shields the oil/fat molecules from the water making it soluble. Anything that is soluble will be washed away with the water.

Effect of the alkali

The type of alkali metal used determines the kind of soap product. Sodium soaps, prepared from sodium hydroxide, are firm, whereas potassium soaps, derived from potassium hydroxide, are softer or often liquid. Historically, potassium hydroxide was extracted from the ashes of bracken or other plants. Lithium soaps also tend to be hard—these are used exclusively in greases.

Effects of fats

Soaps are derivatives of fatty acids. Traditionally they have been made from triglycerides (oils and fats). Triglyceride is the chemical name for the triesters of fatty acids and glycerin. Tallow, i.e., rendered beef fat, is the most available triglyceride from animals. Its saponified product is called sodium tallowate. Typical vegetable oils used in soap making are palm oil, coconut oil, olive oil, and laurel oil. Each species offers quite different fatty acid content and hence, results in soaps of distinct feel. The seed oils give softer but milder soaps. Soap made from pure olive oil is sometimes called Castile soap or Marseille soap, and is reputed for being extra mild. The term "Castile" is also sometimes applied to soaps from a mixture of oils, but a high percentage of olive oil.

For more information visit:-

https://en.wikipedia.org/wiki/Soap

https://todayinsci.com/8/8_22.htm

http://www.prlabs.co.uk/lab-supplies.php?N=ammonia-buffer-soln&Id=57114

On this day in science – the rubber fire hose was patented

In 1821, a fire hose of cotton web lined with rubber was patented by James Boyd of Boston, Mass. He invented it to replace riveted leather hose. Leather hose had many drawbacks, including drying out, cracking and bursting from excessive pressure. The introduction of rivets (1807), to replace stitching, had allowed higher pressures and greater delivery of water on the fireground. The improved hose now was 40 to 50 feet in length and weighed more than 85 pounds with the couplings. Hose oilers were developed to keep the leather supple and pliable. Various types of oils and other substances were used to keep the hose in shape. By 1871, the Cincinnati Fire Department was using the B.F. Goodrich Company's new rubber hose reinforced with cotton ply.

Indoor fire hose with a fire extinguisher, by Raysonho @ Open Grid Scheduler / Grid Engine (Own work) [CC0], via Wikimedia Commons

Modern fire hoses use a variety of natural and synthetic fabrics and elastomers in their construction. These materials allow the hoses to be stored wet without rotting and to resist the damaging effects of exposure to sunlight and chemicals. Modern hoses are also lighter weight than older designs, and this has helped reduce the physical strain on firefighters. Various devices are becoming more prevalent that remove the air from the interior of fire hose, commonly referred to as fire hose vacuums. This process makes hoses smaller and somewhat rigid, thus allowing more fire hose to be packed or loaded into the same compartment on a fire fighting apparatus.

There are several types of hose designed specifically for the fire service. Those designed to operate under positive pressure are called discharge hoses. They include attack hose, supply hose, relay hose, forestry hose, and booster hose. Those designed to operate under negative pressure are called suction hoses.

For more information visit:-

https://todayinsci.com/5/5_30.htm

https://en.wikipedia.org/wiki/Fire_hose

http://www.prlabs.co.uk/lab-supplies.php?N=balls-rubber-20mm-&Id=46943

On this day in science history: the Hindenburg Zeppelin arrived at Lakehurst, New Jersey, USA

In 1936, the Hindenburg Zeppelin arrived at Lakehurst, New Jersey, USA, from Germany marking the beginning of a regular transatlantic passenger service. The flight, carrying 51 passengers and 56 crew, took 61 hours.

Hindenburg at Lakehurst, by U.S. Department of the Navy. Bureau of Aeronautics. Naval Aircraft Factory, Philadelphia, Pennsylvania (USA). [Public domain], via Wikimedia Commons

The Hindenburg was a large German commercial passenger-carrying rigid airship, the lead ship of the Hindenburg class, the longest class of flying machine and the largest airship by envelope volume. It was designed and built by the Zeppelin Company (Luftschiffbau Zeppelin GmbH) on the shores of Lake Constance in Friedrichshafen and was operated by the German Zeppelin Airline Company (Deutsche Zeppelin-Reederei). The Hindenburg had a duralumin structure, incorporating 15 Ferris wheel-like bulkheads along its length, with 16 cotton gas bags fitted between them. The bulkheads were braced to each other by longitudinal girders placed around their circumferences. The airship's outer skin was of cotton doped with a mixture of reflective materials intended to protect the gas bags within from radiation, both ultraviolet (which would damage them) and infrared (which might cause them to overheat). The gas cells were made by a new method pioneered by Goodyear using multiple layers of gelatinized latex rather than the previous goldbeater's skins. In 1931 the Zeppelin Company purchased 5,000 kg (11,000 lb) of duralumin salvaged from the wreckage of the October 1930 crash of the British airship R101, which might have been re-cast and used in the construction of the Hindenburg.

The interior furnishings of the Hindenburg were designed by Fritz August Breuhaus, whose design experience included Pullman coaches, ocean liners, and warships of the German Navy. The upper "A" Deck contained small passenger quarters in the middle flanked by large public rooms: a dining room to port and a lounge and writing room to starboard. Paintings on the dining room walls portrayed the Graf Zeppelin's trips to South America. A stylized world map covered the wall of the lounge. Long slanted windows ran the length of both decks. The passengers were expected to spend most of their time in the public areas, rather than their cramped cabins.

The lower "B" Deck contained washrooms, a mess hall for the crew, and a smoking lounge. Harold G. Dick, an American representative from the Goodyear Zeppelin Company, recalled "The only entrance to the smoking room, which was pressurized to prevent the admission of any leaking hydrogen, was via the bar, which had a swiveling air lock door, and all departing passengers were scrutinized by the bar steward to make sure they were not carrying out a lit cigarette or pipe."

Helium was initially selected for the Hindenburg’s lifting gas because it was the safest to use in airships, as it is not flammable. One proposed measure to save helium was to make double-gas cells for 14 of the 16 gas cells; an inner hydrogen cell would be protected by an outer cell filled with helium, with vertical ducting to the dorsal area of the envelope to permit separate filling and venting of the inner hydrogen cells. At the time, however, helium was also relatively rare and extremely expensive as the gas was only available in industrial quantities from distillation plants at certain oil fields in the United States. Hydrogen, by comparison, could be cheaply produced by any industrialized nation and being lighter than helium also provided more lift. Because of its expense and rarity, American rigid airships using helium were forced to conserve the gas at all costs and this hampered their operation.

Despite a U.S. ban on the export of helium under the Helium Control Act of 1927, the Germans designed the airship to use the far safer gas in the belief that they could convince the US government to license its export. When the designers learned that the National Munitions Control Board would refuse to lift the export ban, they were forced to re-engineer the Hindenburg to use hydrogen for lift. Despite the danger of using flammable hydrogen, no alternative lighter-than-air gases could provide sufficient lift. One beneficial side effect of employing hydrogen was that more passenger cabins could be added. The Germans' long history of flying hydrogen-filled passenger airships without a single injury or fatality engendered a widely held belief they had mastered the safe use of hydrogen. The Hindenburg's first season performance appeared to demonstrate this, however the airship was destroyed by fire 14 months later on May 6, 1937, at the end of the first North American transatlantic journey of its second season of service. Thirty-six people died in the accident, which occurred while landing at Lakehurst. This was the last of the great airship disasters; it was preceded by the crashes of the British R38 in 1921 (44 dead), the US airship Roma in 1922 (34 dead), the French Dixmude in 1923 (52 dead), the British R101 in 1930 (48 dead), and the US Akron in 1933 (73 dead).

For more information visit:-

https://todayinsci.com/5/5_09.htm

https://en.wikipedia.org/wiki/Hindenburg-class_airship

http://www.prlabs.co.uk/lab-supplies.php?N=sodium-hydrogen-carbonate&Id=58910

On this day in history: the first synthetic rubber was announced

On 2^nd November 1931, the DuPont company, of Wilmington, Delaware, announced the first synthetic rubber. It was known as DuPrene, and from 1936 as Neoprene. Many scientists were trying to make natural rubber in the 1920s and 30s. One of the Wallace Carothers team, Gerard Berchet, had left a sample of monovinylacetylene in a jar with hydrochloric acid (HCl) for about five weeks. 

Then on 17 Apr 1930, coworker Arnold M. Collins happened to look in that jar and found a rubbery white material. The HCl had reacted with the vinylacetylene, making chloroprene, which then polymerized to become polychloroprene. The new rubber was expensive, but resisted oil and gasoline, which natural rubber didn't. It was the first good synthetic rubber.

In 1935, German chemists synthesized the first of a series of synthetic rubbers known as Buna rubbers. These were copolymers, meaning the polymers were made up from two monomers in alternating sequence. Other brands included Koroseal, which Waldo Semon developed in 1935, and Sovprene, which Russian researchers created in 1940. B.F. Goodrich Company scientist Waldo Semon developed a new and cheaper version of synthetic rubber known as Ameripol in 1940.

The production of synthetic rubber in the United States expanded greatly during World War II, since the Axis powers controlled nearly all the world's limited supplies of natural rubber by mid-1942 once Japan conquered Asia. Military trucks needed rubber for tyres, and rubber was used in almost every other war machine. The U.S. government launched a major (and largely secret) effort to improve synthetic rubber production. A large team of chemists from many institutions were involved, including Calvin Souther Fuller of Bell Labs. The rubber designated GRS (Government Rubber Styrene), a copolymer of butadiene and styrene, was the basis for U.S. synthetic rubber production during World War II. By 1944, a total of 50 factories were manufacturing it, pouring out a volume of the material twice that of the world's natural rubber production before the beginning of the war. It still represents about half of total world production.

Operation Pointblank bombing targets of Nazi Germany included the Schkopau (50K tons/yr) plant and the Hüls synthetic rubber plant near Recklinghausen (30K, 17%), the Kölnische Gummifäden Fabrik tire and tube plant at Deutz on the east bank of the Rhine. The Ferrara, Italy, synthetic rubber factory (near a river bridge) was bombed August 23, 1944. Three other synthetic rubber facilities were at Ludwigshafen/Oppau (15K), Hanover/Limmer (reclamation, 20K), and Leverkusen (5K). A synthetic rubber plant at Oświęcim in Nazi-occupied Poland, was under construction on March 5, 1944.

World War Two poster about synthetic rubber tyres

Solid-fuel rockets during World War II used nitrocellulose for propellants, but it was impractical and dangerous to make such rockets very large. During the war, California Institute of Technology (Caltech) researchers came up with a new solid fuel based on asphalt mixed with an oxidizer (such as potassium or ammonium perchlorate), and aluminium powder. This new solid fuel burned more slowly and evenly than nitrocellulose, and was much less dangerous to store and use, but it tended to slowly flow out of the rocket in storage and the rockets using it had to be stockpiled nose down.

After the war, Caltech researchers began to investigate the use of synthetic rubbers to replace asphalt in their solid fuel rocket motors. By the mid-1950s, large missiles were being built using solid fuels based on synthetic rubber, mixed with ammonium perchlorate and high proportions of aluminium powder. 

Such solid fuels could be cast into large, uniform blocks that had no cracks or other defects that would cause non-uniform burning. Ultimately, all large solid-fuel military rockets and missiles would use synthetic-rubber-based solid fuels, and they would also play a significant part in the civilian space effort.

Additional refinements to the process of creating synthetic rubber continued after the war. The chemical synthesis of isoprene accelerated the reduced need for natural rubber, and the peacetime quantity of synthetic rubber exceeded the production of natural rubber by the early 1960s.

Nowadays synthetic rubber is used a great deal in printing on textiles. In this case it is called rubber paste. In most cases titanium dioxide is used with copolymerization and volatile matter in producing such synthetic rubber for textile use. Moreover, this kind of preparation can be considered to be the pigment preparation based on titanium dioxide.

For more information visit:-

http://www.todayinsci.com/11/11_02.htm

https://en.wikipedia.org/wiki/Synthetic_rubber

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