G - Polymer Processing Glossary of Terms

Gate - An orifice through which the molten resin enters the cavity.
Gate blush - A blemish or disturbance in the gate area of an injection molded article. It occurs when the melt fractures in leaving the gate due to relaxation of elastic forces.
Gel permeation chromatography - A device used to determine the molecular weight distribution of a polymer.
GPC - An abbreviation for Gel Permeation Chromatography.
Guide pins - Devices to maintain proper alignment for molds.

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