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The plastic and the coffee grinder
Of numerous coffee grinders of the 30s and 40 contain a plastic component called usually Bakelite
( They are generally, drawers, hoppers, buttons but it can be also the mill in its integer).
1.That as it is called plastic ?
We call plastic any material which can be formed or molded, for example, the clay is a plastic, but collectively, it is synthetic materials which were of use to the molding or to the shaping of objects that we call plastic.
The first materials plastic were with natural polymer such as the rubber, the cellulose or the casein (the polymer is the basic resin which is going to be of use to the manufacturing of the plastic).
2.The big dates of plastics with natural polymer :
1839 : Charles Goodyear discovers the process of vulcanization of the rubber.
1870 : The brother Hyatt invents the celluloid (base cellulose of the wood) which will at first serve to make billiard balls.
The celluloid is considered as the first artificial plastic
1884 : Hilaire De Chardonnet invent the viscose.
1889 : Jean-Jacques Trillat invent the Galalithe (base casein of the milk) which is going to replace the ivory or the horn for billiard balls, buttons, pens etc.
Then plastics with synthetic polymer came from 1907
There are two big families of industrial synthetic plastics:
the thermodurcissables : At present approximately 10 % of the plastic materials
Are stiff and fragile but have a good behaviour in the temperature
They take their shape after the chemical reaction ( polymérisation ) and cannot be any more modified.
It is the case of the Bakelite.
The thermoplastic : Approximately 90 % of the plastic materials
Are flexible and have an inferior resistance in the heat
Unlike the precedents they can deform and be shaped under the influence of the heat , What makes them recyclable.
They are, for example: polyamide (nylon), lexan, teflon, PVC, polyethylene etc....
It is the Second World War which aggravated the plastic need and, the finished war, the moose breathed by this one into the industrial and scientific world continued and became more marked.
Numerous plastics were invented and nowadays replace the often more expensive metallic parts, subject to corrosion and heavier.
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