BMC - Bulk Molding Compound

Bulk Molding Compounds (BMC) are used in compression, transfer and injection molding processes. BMC is available in bulk bags as well as slug form. The mixing operation can be done in a number of ways. Premix employs three methods for combining glass with paste, a continuous screw mixer, a sigma blade mixer and a plough blade mixer. The process chosen is dependent upon specific product properties, product form and volume.

BMC is a thermoset plastic made up of a polymer resin, various inert fillers, fiber reinforcement, catalysts, stabilizers, and pigments that form a viscous, 'play-dough like' compound for molding. BMC is highly filled and reinforced with short fibers. Glass reinforcement ranges between 5% to 30% and with glass length typically between 1/8" to 1/2".

Depending on the end-use application, compounds are formulated to achieve tight dimensional control, flame resistance, high dielectric strength, corrosion, and stain resistance and color stability. Its excellent flow characteristics make BMC well suited to a wide variety of applications requiring precision in detail and dimensions. The material is available in a wide variety of colors.