BE-15 Pipes and Materials: Welding of Plastic Pipes
Fundamentals concerning plastics
Definitions
Plastics:
Macromolecular materials with varied application fields; polymers that are artificially manufactured by chemical techniques. Thus, these organic materials do not appear in nature.
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Chemical techniques for the manufacturing of plastics:
One differentiates between polymerisation, polycondensation and polyaddition.
Polymerisation:
The composition of simpler chemical compounds (=monomers) forming absolute homopolar compounds into polymer, chain-shaped macromolecules, e.g. ethylene into polyethylene plastic.
Polyaddition:
Chemical combination of simpler chemical compounds (=monomers) into polymer molecules (=macromolecules) by the reaction of functional groups.
Polycondensation:
Chemical combination of simpler chemical compounds (=monomers) into polymer molecules (macromolecules) by separation of water or other smaller molecules.
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