Sheet Molding Compounds (SMC)
Sheet Molding Compound Offers Superior Strength and Electrical Insulation
Sheet Molding Compound (SMC) is a compression molding compound often used for larger parts where higher mechanical strength is needed. SMC is a fiber reinforced thermoset material. Glass reinforcement is between 10% and 60%, and glass length is slightly longer than Bulk Molding Compound (BMC) - between 1/2-inch and 1-inch (25mm).
Thermoset Sheet Molding Compound (SMC) is a mixture of polymer resin, inert fillers, fiber reinforcement, catalysts, pigments and stabilizers, release agents, and thickeners and possesses strong dielectric properties. Manufacture of sheet molding compounds is a continuous in-line process. The material is sheathed both top and bottom with a polyethylene or nylon plastic film to prevent auto-adhesion. The paste is spread uniformly onto the bottom film. Chopped glass fibers are randomly deposited onto the paste. The top film is introduced and the sandwich is rolled into a pre-determined thickness. The sheet is allowed to mature for 48 hours.
Sheet molding compounds can be molded into complex shapes. Superior mechanical properties and surface appearance, plus excellent electrical insulation make this thermoset material ideal for automotive Class A body panels, high-strength electrical parts, business equipment cabinets, personal watercraft, and various structural components.
Bulk Molding Compounds (BMC)
Bulk Molding Compound Offers Excellent Flow Characteristics
Bulk Molding Compound (BMC) is a thermoset plastic resin blend of various inert fillers, fiber reinforcement, catalysts, stabilizers, and pigments that form a viscous, 'puttylike' injection molding compound. Bulk Molding Compound (BMC) is highly filled and reinforced with short fibers. Glass reinforcement represents between 10% and 30%, with glass length typically between 1/32-inch and 1/2-inch (12.5mm). Depending on the end-use application, bulk molding compounds are formulated to achieve close dimensional control, flame and track resistance, electrical insulation, corrosion and stain resistance, superior mechanical properties, low shrink, and color stability. Its excellent flow characteristics, dielectric properties, and flame resistance make this thermoset material well-suited to a wide variety of applications requiring precision in detail and dimensions as well as high performance. The material is available in a broad selection of colors, and can tolerate powder-coat or water-based paint.