Klatte
Klatte, Friedrich Heinrich August
ACHIEVEMENT(S): PVC
NICKNAME/ALIAS: known as Fritz Klatte
DATE/PLACE OF BIRTH: Diepholz28 March 1880,
DATE/PLACE/AGE AT DEATH: 1934
DISCIPLINE: Chemist
FIELD: Industrial chemistry
LANGUAGE: German
PARENTS: ?
SIBLINGS: ?
SPOUSE: ?
CHILDREN: ?
EDUCATION: ?
MAJOR WORK: 'The Work on Vinyl Esters at Griesheim', 1929
LIFE AND TIMES:
The birth of PVC can be traced back to the initial preparation of the monomer vinyl chloride by the French chemist Regnault* in 1835. Forty years later, in 1872, Eugen Baumann observed that on exposure to sunlight in sealed tubes vinyl bromide and chloride were converted from liquids to powdery solids. Although he had no idea of the nature of the solid materials, his investigations showed that they were chemically resistant, unaffected by either acids or alkalis.
Then, in 1912, two further important steps were taken. First, the Russian chemist Ostromislensky, patented a process for obtaining artificial rubber from polymerized vinyl bromide, and vinyl chloride. During his investigations, he noticed that the polymers could be prepared by the action of sunlight from the monomer alone and also in solvents, such as benzene or carbon disulphide, producing rigid substitutes for ebonite, gutta percha, and celluloid applications.
The second development of 1912 was the discovery (patented 11 October 1912) by Fritz Klatte, for the Chemische Fabrik Griesheim Elektron of Frankfurt am Main, that vinyl chloride could be made by the addition of hydrogen chloride to acetylene.
This was at a time when the development 20 years earlier by the French chemist Moissan* of a profitable method for commercially producing acetylene (1892) had led to the research departments of many chemical works investigating the products of acetylene reactions, particularly once the value of acetylene used for lighting had been reduced by new efficient and cheaper electric generators around 1910.
Emil Zacharias led the research at the Mainthalwerke of Griesheim Elektron, which began work in this field with investigations of the chlorination products of acetylene in 1904. However, it was not until 1910 that he became extremely interested in the possibilities of the technical application of acetylene, and the team, including Klatte, began working on the isolation of organic vinyl esters (organic compounds that react with water to produce alcohols and organic or inorganic acids). Klatte had achieved this by preparing the first known vinyl esters in 1912, and then acetylene was reacted with acetic acid using a catalyst of mercury salts.
Over the following years, Klatte prepared a large number of vinyl esters including the formate, propionate, butyrate, isovalerate, mono- and trichloracetates, benzoate, chlorbenzoate salicylate, cinnamate, phenyl acetate and phenoxyacetate. He was interested not only in the reaction of acetylene and organic acids, but also of acetylene and inorganic acids, in particular the hydrogen halides.
This led to the preparation of vinyl chloride and bromide, by heating a mixture of acetylene and hydrogen chloride over a mercury catalyst. In the patent of 1912, the method of producing the new substance, vinyl chloride, is: porous material (e.g. pumice, coke etc) impregnated with mercury chloride is heated to 180C in a tube, and then equal volumes of acetylene and dry hydrogen chloride are passed through the tube and the vinyl chloride produced is either condensed in cooled vessels or compressed. This description was to become the basis of the process which has since been used to synthesize millions of tons of vinyl chloride.
This patent was accompanied by two others, on the synthesis of vinyl bromide and vinyl acetate from acetylene, and the conversion of acetylene into acetaldehyde, and was then followed by a series of patents from Griesheim on the polymerization of these monomers, with methods whereby the products could be put to good use.
However, at that time Klatte's large body of work led to no immediate further developments, as commercial application of PVC was limited by its extreme rigidity, and such was the lack of interest in his materials that on the last day of 1926 the patents were allowed to lapse by Griesheim, with Klatte's consent.
The main reason was that Klatte's discovery came too early, as there was in the 1910s no reliable and economic process for the manufacture of the monomers, plus the large-scale polymerization process remained unsatisfactory, in large part, because Hermann Staudinger had not yet demonstrated that polymers were long-chain molecules (1922), information which would prove invaluable to future synthesizers. Also, synthesized polymers remained at this time far more expensive than natural products. Even at the beginning of the 1930s they were about five times as expensive as linseed oil and natural resins. So by the end of World War I Klatte's research was directed elsewhere.
In 1926, while trying to dehydrohalogenate PVC in a high-boiling solvent in order to obtain an unsaturated polymer that might bond rubber to metal, the American chemist Waldo Lonsbury Semon, of the B.F. Goodrich Company in the United States, discovered that polyvinyl chloride could be plasticized (i.e. made pliable) with high-boiling liquids like tritolyl phosphate to give a rubber-like mass - what is now called plasticized PVC. The discovery of this flexible, inert product was responsible for the commercial success of the polymer from 1930.
Another route to a flexible product was copolymerization: in 1930 theUnion Carbide Corporation introduced the trademarked polymer Vinylite, a copolymer of vinyl chloride and vinyl acetate that became the standard material of long-playing phonograph records.
ASSESSMENT: His work led to the discovery of modern plastics.
EXTRA CONNECTIONS: His work led to plastics*
ONELINER: Fritz Klatte, whose work led to plastics
BIBLIOGRAPHY:
DSB, EB, History of Technology,
Kaufman, Morris, The History of PVC, London: Maclaren and Sons, 1959
Multimedia:
Polymer PVC (video)