Walter Bock

from Wikipedia, the free encyclopedia

Walter Bock (born January 20, 1895 in Wenzen , † October 25, 1948 in Cologne ) was a German chemist . He researched the emulsion polymerization of 1,3-butadiene and styrene in the Leverkusen laboratories of IG Farben . In 1929 he succeeded in producing styrene-butadiene rubber , a synthetic rubber.

Life

Walter Bock was the fourth of nine children of the cantor Wilhelm Bock (* May 28, 1845; † September 8, 1914) and his wife Hermine, b. Peckmann. After completing school in Wenzen and Braunschweig and serving as a war volunteer, he studied chemistry at the universities of Hanover , Tübingen (2nd and 3rd semester) and Göttingen , where he received his doctorate in 1921 under Adolf Windaus , the work was entitled I. On Responsiveness of methylene in 2 isomeric dinitrotoly acetic acids and the associated methyl ketones. II. About the reactivity of the halogen in 3-nitro-4-chlorobenzaldehyde and in 3-nitro-6-chlorobenzaldehyde .

He found his first job in the Premnitz plant in the Rottweil powder factory ; In 1926 he went to IG Farbenindustrie AG at the Leverkusen plant .

Walter Bock married Margarete Rodenberg from Bad Oeynhausen in 1923 , who died in Cologne in 1997 at the age of 97. The marriage had two children.

Walter Bock was a tinkerer and a musical person who, in addition to his professional activity, was very close to nature and loved his homeland. He liked to go hiking in the Eifel , he also had a poetic streak and wrote poems and two plays.

On October 25, 1948, as he did every month, he met with friends. One of these friends dropped him off on the way back not far from his apartment in Cologne , from where he wanted to walk the last part of the way as usual. However, he did not reach his home and was later found dead.

On his 100th birthday, Walter Bock's daughter Rosemarie had a memorial stone erected in front of the house where he was born, the schoolhouse in Wenzen, on the initiative of the local homeworker, symbolizing the use of SBR in car tires.

power

Walter Bock's professional services were supported by the former operations manager of Bayer's Leverkusen plant, Dr. Dietrich Rosahl, in his posthumous laudation on the occasion of Walter Bock's admission to the International Rubber Science Hall of Fame at the University of Akron, USA. In 1926, Bock studied the polymerization of isoprene . At this time, Leverkusen began to resume the development of rubber chemicals after it was discontinued at the end of the war in 1918.

At the end of 1926, Bock was able to polymerize isoprene in an aqueous emulsion with the addition of small amounts of peroxide in the "short" time of 25 days at 30-40 ° C. The polymer achieved a tensile strength of 8 MPa (= 8 N / mm²), an elongation at break of 400% with good elasticity .

The synthetic polyisoprene gave the same chemical analysis values as natural rubber; only it couldn't be produced in the quality of natural rubber.

Some of his colleagues may have criticized him for not being able to implement a synthesis problem that had been solved in itself.

As a result, Bock shifted his attention to the processing of synthetic polymers and found that a copolymer he had obtained showed a significant increase in its performance indicators after adding carbon black .

In doing so, as the young chemist he was, he departed from the prevailing view of the effects of carbon black on vulcanizates. There was talk of dirt effects.

Bock's new objective was the synthesis of further copolymers based on 1,3-butadiene or isoprene with the addition of so-called comonomers . He used substances that, as homopolymers, had thermoplastic properties. He found the right comonomer in styrene .

In order to test the usability of the new rubber, car tires were manufactured with profiles made of vulcanized butadiene-styrene rubber (internationally known as SBR Styrene Butadiene Rubber ) with the addition of carbon black. Test drives on the Nürburgring in 1931 were promising, so research work on SBR was continued. This although the polymerization process was difficult to control.

Bock's research in the following years remained emulsion polymerization. In 1929 IG Farbenindustrie AG received the first associated patent. At the end of the 1930s, Bock managed to improve the adhesion of SBR to the steel cord of the carcass by adding polyhydric phenols to the rubber compound.

In the spring of 1937, 200 to. SBR is produced under the brand name Buna S in a specially built facility in Schkopau (see web links: Lanxess AG) .

Butadiene-styrene was the first commercially viable synthetic rubber . It is the most widely used synthetic rubber today and is used particularly in the manufacture of tires , seals and conveyor belts .

estate

Bock's estate, especially his autobiographical fragments , are archived in the Einbeck city archive.

literature

  • Georg Schwedt: Plastic, elastic, and fantastic: it doesn't work without plastics . John Wiley & Sons, 2013, ISBN 978-3-527-66530-3 , pp. 74 ( limited preview in Google Book search).
  • Axel Requardt: Walter Bock (1895 - 1948) life in the shadow of a great moment . In: Einbecker yearbook . tape 52 , 2014, p. 147-200 .
  • Axel Requardt: Walter Bock (1895 - 1948) and the invention of the Buna . In: Yearbook of the Cologne History Association . tape 82-83 , 2015, pp. 291-333 . , doi : 10.7788 / jbkgv-2015-0109 .

Web links

Individual evidence

  1. ↑ death certificate, loc.cit. at Axel Requardt, quote 74
  2. ^ Bayer AG, press release, 50 years of emulsion SBR, The University of Akron honors inventor Walter Bock ; Leverkusen, January 1980
  3. ↑ Elke Heege: Dr. Walter Bock 100 years (1895-1949) . In: Einbecker yearbook. 44, 1995, pp. 209-214.
  4. ↑ Private communication from the family (2015)
  5. ^ Introduction of the article by Requardt in the Cologne History Association
  6. ↑ A work by the sculptor Stephanie Link, Coppengrave , 1995.
  7. ↑ Dietrich Rosahl (Bayer AG): Laudation given on the occasion of Walter Bock's admission as 19th honoree to the International Rubber Science Hall of Fame at the University of Akron, Ohio, USA, on October 27, 1979.
personal data
SURNAME Bock, Walter
BRIEF DESCRIPTION German chemist
DATE OF BIRTH January 20, 1895
PLACE OF BIRTH Wenzen , Germany
DATE OF DEATH October 25, 1948
Place of death Cologne