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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.
The first industrially practical polyethylene synthesis discovered by Eric Fawcett and Reginald Gibson at the Imperial Chemical Industries (ICI) works in Northwich, England. [10] 1935 Nylon is invented and patented by DuPont [6] 1938: Nylon is first used for bristles in toothbrushes. It features at the 1939 worlds fair and is famously used in ...
Together with the invention of the practical fountain pen and the mass-produced pencil of the same period, and in conjunction with the advent of the steam driven rotary printing press, wood based paper caused a major transformation of the 19th-century economy and society in industrialized countries. With the introduction of cheaper paper ...
The plastic kits and covers are mostly made of synthetic polymers like polythene, and tires are manufactured from polybutadienes. [1] However, due to the environmental issues created by these synthetic polymers which are mostly non-biodegradable and often synthesized from petroleum, alternatives like bioplastics are also being considered.
Parkesine, invented by Alexander Parkes in 1855 and patented the following year, [133] is considered the first man-made plastic. It was manufactured from cellulose (the major component of plant cell walls) treated with nitric acid as a solvent.
Later, he invented a simpler celluloid production process, receiving several hundred patents. Among the most well-known of his inventions was that of a substitute for ivory to produce billiard balls. An award of $10,000 had been instituted by Michael Phelan in 1863 due to the cost of ivory and concerns on its shortage. [1]
They began working together in 1946, and in 1951 invented "crystalline polypropylene" and high-density polyethylene (HDPE). These plastics were initially known by the name Marlex. The polymerization of ethylene was made possible by their discovery of the so-called Phillips catalyst. [1]
A common post-extrusion process for plastic sheet stock is thermoforming, where the sheet is heated until soft (plastic), and formed via a mold into a new shape. When vacuum is used, this is often described as vacuum forming. Orientation (i.e. ability/ available density of the sheet to be drawn to the mold which can vary in depths from 1 to 36 ...