Standard Practice for Compression Molding Test Specimens of Thermosetting Molding Compounds

Importancia y uso:

5.1 The conditions at which compounds are molded are known to influence the properties of the specimens. The degree of cure, elimination of knit-lines between particles, density of the part, and degradation of the polymer are among those factors which will be affected by the molding conditions. Thus it is important to conform to a standard set of conditions in order to have a valid comparison of properties between different compounds and different batches of the same compound.

5.2 Molded specimens showing evidence of low-density areas due to trapped gases shall be discarded. A breathe step can be incorporated to eliminate this situation. If used, it is critical that the breathe step be as brief as possible to avoid precuring of the compound before full pressure is applied leading to poorly “knitted” areas and lower strength in the molded specimen.

Subcomité:

D20.09

Referida por:

D1636-21, D6289-13R19, D0704-99R20

Volúmen:

08.03

Número ICS:

77.180 (Equipment for the metallurgical industry)

Palabras clave:

allyl molding compound; amino molding compound; compression molding; phenolic molding compound; plastics; thermoset;