V - Polymer Processing Glossary of Terms

Variation - A change in the value of a measured characteristic.
Vent - A shallow channel in the mold to allow air to escape from the cavity during injection.
Virgin Material - Plastic material that has not been subject to use or processing other than that required for its initial manufacture.
Viscosity - Internal friction or resistance to flow of a melt or liquid. The constant ratio of shearing stress to shearing rate. It is a measure of the materials resistance to flow.

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