Answer:
- Elevated temperatures.
- Elevated pressures.
Explanation:
In the manufacture of plastic products are used:
Raw material (pellets) which are the monomers that promote the chemical reaction.
To these are added the charges, in order to reduce the cost of the final product and improve some properties. These charges can be fiberglass, paper, metal structures.
Additives are also added whose mission is to improve or achieve certain properties, such as reducing friction, reducing chemical degradation, increasing electrical conductivity, coloring the product, and all this happens in the presence of a catalyst that is responsible for initiating and accelerating the chemical reaction process.
There are different methods of production of plastics, one of the most frequent is by injection.
Injection is a process that is carried out on machines similar to extrusion machines, in which the spindle, in addition to rotating, has an axial displacement.
In the injection, once the mold is filled, it is separated from the nozzle of the machine, breaking the feed channel. After a certain time, the piece already cooled is demoulded.
High pressures and temperatures are necessary, but parts of good finish and at high production speeds are obtained
= characteristic wavelength = 9 μm = 9 x 10⁻⁹ m