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Hans Freiherr [a] von Pechmann (1 April 1850 – 19 April 1902) was a German chemist, renowned for his discovery of diazomethane in 1894. [ 1 ] [ 2 ] Pechmann condensation [ 3 ] [ 4 ] and Pechmann pyrazole synthesis . [ 5 ]
Polyethylene was first synthesized by the German chemist Hans von Pechmann, who prepared it by accident in 1898 while investigating diazomethane. [12] [a] [13] [b] When his colleagues Eugen Bamberger and Friedrich Tschirner characterized the white, waxy substance that he had created, they recognized that it contained long −CH 2 − chains and termed it polymethylene.
1898: Synthesis of polyethylene, the most common plastic, by Hans von Pechmann [160] 1898: First synthesis of purine by Emil Fischer. He had also coined the word in 1884. [161] Early 20th century: Schlenk flask by Wilhelm Schlenk [162] 1900s: Haber process by Carl Bosch and Fritz Haber [134] 1902: Ostwald process by Wilhelm Ostwald [163]
The earliest beginnings of polyethylene-based pipes occur when German scientist, Hans von Pechmann, discovered a waxy residue at the bottom of a test tube, colleagues Eugen Bamberger and Friedrich Tschirner called it polymethylene but it was discarded as having no commercial use at the time. [14] 1904
Polyethylene is first synthesized by German chemist Hans von Pechmann. Exploration. January 30–February 13 ...
Polyethylene is a commonly used plastic and can be found in packaging, bags, insulation, and water pipes. Higher microplastic concentrations in brain compared to other organs.
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