Thermoplastics shrinkage testing

Plastics - Injection moulding of test specimens of thermoplastic materials - Part 4 Determination of moulding shrinkage... [Pg.344]

Rheological test more often used for product quality control is a measurement of the elastic recovery in polymer melts and their compounds. This is usually accomplished by measuring the swell (or shrinkage) of materials undergoing extrusion. The tendency of polymers, whether thermoplastic or rubber, to enlarge when emerging from an extruder die is called die swell. [Pg.298]

Plastics—Injection Moulding of Test Specimens of Thermoplastic Materials—Part 4 Determination of Moulding Shrinkage... [Pg.965]

Low Profile Additives are additives consisting of thermoplastics. They got their name from a test used early in their development to measure performance. Because these materials decreased shrinkage when added as a styrene solution they allowed for better mold reproduction. A pro-filometer used to measure steel smoothness was employed on the molded panels to trace the surface. The composites with the best mold reproduction from smooth surfaces gave fewer and lower peaks and valleys, hence a lower profile. Examples of profilometer tracings with and without low profile additives are shown in Figures 1 and 2. [Pg.444]

Standard Test Method of Measuring Shrinkage from Mold Dimensions of Thermoplastics, 2008... [Pg.1362]

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