Introduction to MID Materials Classes

Plastics are commonly further subdivided in terms of the degree to which their molecular chains are crosslinked, and by their composition and internal structure, as shown in Fig. 2.2. 

Molding compounds based on epoxy or phenolic resins mixed with fillers are used for the conventional printed-circuit board technologies widely employed in electronics production. These molding compounds belong to the group of thermoset plastics. They consist of tightly crosslinked macromolecules, as reflected in their extremely hard and brittle material behavior at room temperature. 

Depending on their basic cured condition, they can become harder when heated, but they do not soften. Thermoset piastics do not melt, so they cannot be welded [48]. 

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