Injection Molding BMC Thermosets
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BMCs, or Bulk Molding Compounds, are a type of thermoset material that are unsaturated polyesters or vinyl esters, and may be injection molded on horizontal molding machines. The properties of BMC molded parts exhibit exceptional dielectric strength, electrical insulation, heat resistance, and chemical resistance lending BMCs to be molded in a variety of safety-critical applications and component assemblies within the Electrical, Automotive, and Industrial markets. In its raw state, BMC resembles a play-dough like form and is filled with glass fibers or mineral fillers dispersed within the resin system to provide strength. Molding wise, BMCs are more commonly injection molded, but can also be compression or transfer molded. Injection molding BMCs require the use of a stuffer or ram to help inject material into the screw and barrel to preheat and plasticize prior to injecting into the molds. (more…)
As a performance grade composite, thermoset plastics are used in a variety of challenging automotive environments and applications. Thermosets provide excellent heat resistance and temperature deflection to avoid deforming or degradation when exposed to high operating temperatures. Utilizing an injection molding process with thermoset not only gives an automotive part the physical and durability properties, but provides a high-throughput option for high volume programs that require large outputs of product. Injection molding thermosets use faster cycle times than compression, and injection molds can built with higher cavitation as well. Automotive applications that rely on injection molded thermoset parts include powertrain and 
Thermosets are a molding material used in a variety of products and industries due to the materials durability within high temperatures and electrical environments. While the Electrical and Automotive are two heavy users of thermoset molded components, another industry that relies on thermosets are the home and consumer appliance market. Whether a product is a larger home appliance or countertop cookware appliance, thermosets parts are used for heating elements and components that touch or are near high operating temperatures or requiring protection against electrical elements. Thermosets can be molded with different textures or surface finishes, and BMC thermoset materials can also be molded with color. Other appliance applications such as 
Phenolic, or phenolic molding compound, is a type of thermoset molding material. Phenolic materials have history dating all the way back to the original plastic, Bakelite, that derived from Leo Baekeland in the early 1900s. Even with a long history, phenolic thermosets are still commonly molded today for different applications and end products requiring heat resistance, electrical strength, and chemical resistance. Molded phenolic components exude excellent dielectric strength and electrical insulation, heat resistance, and chemical resistance. These properties allow phenolics to be molded for a variety of safety-critical components in Electrical, Automotive, and Industrial markets. Phenolics are compounded into a similar shape prior to molding as thermoplastics, in that they are compounded into in a granular form; filled with glass fibers, minerals, or bead fillers dispersed within the resin. Molding wise, phenolics are generally injection molded, but can also be compression or transfer molded. Injection molding phenolics require the use of a molding machine with a screw and barrel to plasticize the material prior to injection. 
Why are thermosets commonly used as a molding material for electrical parts and component assemblies? Thermosets are implemented in electrical applications due to the materials’ exceptional electrical stability, high dielectric strength, and resistance to arc and track which protect internal components from electrical charge and risk of fire or product failure. Parts including circuit breakers, terminal blocks, and electrical connectors are molded from thermoset materials to ensure product safety. Whereas a thermoplastic can degrade, disfigure, or ignite; thermosets such as unsaturated polyester BMC and phenolic molding compounds remain durable and strong when exposed to such electrical elements. From a cost comparison, thermosets are a commercial option available at a low cost per lb. compared to engineered thermoplastics with similar type of electrical and heat resistant properties. Common thermoset materials used in electrical applications include both phenolic and bulk molding compounds (BMC). 
Why are thermoset composites like phenolic and bulk molding compound commonly used material in automotive applications? Molded thermoset parts and components have excellent material properties with regards to resistance against high temperatures, corrosion, and chemicals and automotive fluids. Processing wise, thermosets may be injection molded, or compression molded. 
Phenolics, or phenolic molding compounds, are a type of thermoset composite or plastic molding material. Phenolics have history dating back to the very first plastic, bakelite, that derived from Leo Baekeland in the early 1900s. Despite a long history, phenolics thermosets are still commonly molded today for various applications and end products. The physical properties of molded phenolics provide a molded part or component exceptional dielectric strength, electrical insulation, heat resistance, and chemical resistance. These properties allow phenolics to be molded for a variety of safety-critical components in Electrical, Automotive, and Industrial markets. In its raw state, phenolic is similar to thermoplastics such as nylons or ABS in a granular-like form, filled with glass fibers, minerals, or bead fillers dispersed within the resin. Molding wise, phenolics are generally injection molded, but can also be compression or transfer molded. Injection molding phenolics require the use of a molding machine with a screw and barrel to plasticize the material prior to injection. 
