Sep 17, 2024
The material constant that indicates the ratio of transverse strain to longitudinal strain when a material is deformed is called Poisson’s ratio or transverse strain coefficient.
The Poisson’s ratio describes how much a material shrinks in the transverse direction when it is stretched in the longitudinal direction. Typical values for the Poisson’s ratio for plastics are between 0.3 and 0.5.
A high Poisson’s ratio means that the material shrinks significantly in the transverse direction when stretched longitudinally. The Poisson’s ratio is important for calculating deformations and stresses in complex components and is frequently used in materials science and engineering. Its precise determination is crucial for the design of components in order to correctly predict their deformation behavior under load.
Quality:
Temperature dependence of the Poisson’s ratio for different materials.
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This glossary of plastic industry is provided by PLEXPERT Canada Inc.
Sep 20, 2019
When Monomers with at least two functional groups react to form a polymer the process is called polyaddition.
Double bonds are separated to build new bonds.
Short and long chains react with each other.
The Polyaddition can take place at both ends of the arising chains.
Polyurethane, Polyureas and Epoxy resins are the most important products created through polyadditions.
Plastic:
Polyaddition of Dialcohol and Diisocyanate to Polyurethane.
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This glossary of plastic industry is provided by PLEXPERT Canada Inc.
Sep 22, 2019
When Monomers with at least two functional groups react to form a polymer and produce a byproduct, it is called polycondensation.
The polycondensation can work only properly if the byproduct is taken away continuously.
Otherwise a low polymerisation degree leads to an end of the polycondensation.
A polycondensate with a high molar mass can be produced only with a reaction conversion of more than 99 %.
Furthermore the quantity needs to fit the stoichiometric ratio of the reaction.
Plastic: Polyester and Polyamides for example are produced by
polycondensation.
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This glossary of plastic industry is provided by PLEXPERT Canada Inc.
Jul 2, 2019
Chemical connections of monomers are called polymers.
They are macromolecules with the same inner structure.
Dependent on the amount of monomer types, polymers can be devided into homopolymers (one type of monomers), copolymer (multiple types of monomers) and polymerblends (multiple homopolymers and/or multiple copolymers).
The
Polymer Polyethylene.
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This glossary of plastic industry is provided by PLEXPERT Canada Inc.
Feb 15, 2019
The reaction that takes place when similar or different monomers are converted to polymers is described under the collective term polymerization.
In order to gain macromolecules, the synthesis of plastics is achieved by technical polymerization reactions.
Due to the resulting molecular chains one also speaks in this case of a chain growth reaction.
Plastic: Based on the
monomers Ethylen Polyethylen is created through polimerization.
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This glossary of plastic industry is provided by PLEXPERT Canada Inc.
