Thermoset sheet molding compound SMC

To aid processing flat products, it is helpful to use a sheet molding compound that can be made in a similar manner to a DMC, but with a higher concentration of reinforcement (20% 

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Glass fiber reinforced thermosets Sheet molding compound (SMC) 15 to 30 0.30 to 0.35... 

Special grades of styrenic block copolymers are useful modifiers for sheet molding compounds (SMC) based on thermoset polyesters. They improve surface appearance, impact resistance, and hot strength. 

The matrix can be either a thermoset or thermoplastic. The oldest and still widest used material for compression molded products is phenolic. The thermoset materials used to manufacture fiber reinforced compression molded articles is unsaturated polyester sheet or bulk, reinforced with glass fibers, known as sheet molding compound (SMC) or bulk molding compound (BMC). In SMC, the 25 mm long reinforcing fibers are randomly oriented in the plane of the sheet and make up for 20-30% of the molding compound s volume fraction. 

The resin matrix can be either thermosetting or thermoplastic. Thermosetting resins such as epoxy, polyimide, polyester, and phenolic are used in applications where physical properties are important. Polyester and epoxy composites make up the bulk of the thermoset composite market. Of these two, polyesters dominate by far. Reinforced with glass fiber, these are known as fiberglass-reinforced plastics (FRPs). FRPs are molded by layup and spray-up methods or by compression molding either a preform or sheet molding compound (SMC). 

Such glass fiber-reinforced composites based on the unsaturated polyester thermosets are usually fabricated as sheet molding compounds (SMC) and bulk molding compounds (BMC). These are widely used in various metal replacement applications because of their cost-effectiveness, rigidity, light weight, and corrosion resistance properties particularly useful in transportation (cars and trucks), constmction, pipe, and tank applications. Automotive and tmck body panel and strucmral component applications of SMC include doors, hatchbacks, hoods, front grilles, etc. Some nonautomotive applications of SMC and BMC include sanitaryware (bathtubs, shower stalls, sinks), appliances, business machine, and electrical components. 

ATH came into wide use as a flame retardant in the 1960s, primarily as a result of demands of consumer-driven safety legislation for carpet backing and fiberglass-reinforced polyester products. For these applications, ATH imparts flame retardance and smoke suppression. End-use markets for ATH include transportation, construction, cast polymers, electrical/electronic, wire and cable, leisure and appliances. Specific polymer applications range from thermosets such as solid surface, sheet molding compounds (SMCs) and bulk molding compounds (BMCs) to wire and... 

Sheet-molding compound (SMC) n. A fiberglass-reinforced thermosetting compound in sheet form, usually rolled into coils interleaved with plastic film to prevent autoadhesion. This term was chosen to replace the term prepr, which was deemed to be confusing and insufficiently definitive. SMC can be molded into complex shapes with little scrap, and is low in cost. 

Compression molding, bulk molding compound (BMC), sheet molding compound (SMC), low-pressure molding compound (LPMC), transfer molding, and thermoset injection molding... 

Alkyd thermoset compounds are based on unsaturated polyester resins, which are combined with cross-linking monomers, catalysts, reinforcements, lubricants, and fillers. They are similar to TS polyesters, but have lower levels of monomers. They are part of the group that includes the bulk-molding compounds (BMCs) and sheet-molding compounds (SMCs). Their fast molding cycles at low pressure make them easier to process than other TSs by vacuum, compression, transfer, or injection molding. 

Bulk molding compounds (BMC) and sheet molding compounds (SMC) have gained increased commercial importance in recent years, particularly in the automotive industry. Every yeeir new applications are introduced. BMC and SMC products consist of a thermosetting resin, such as an unsaturated polyester, containing a filler and reinforced with glass fibers. Often the recipe includes a thermoplastic additive known as a low profile additive (LPA) to eliminate cure shrinkage and improve surface quality. Other additives may also be present to control viscosity, add color, and promote mold release. 

Even though glass fibers today are not used very much in the rubber industry, they are still used extensively in the thermoset plastics industry, which includes the making of unsaturated polyester resin composites for boat hulls, car bodies, and so on. They are used extensively in what is called sheet molding compound (SMC) by the automotive industry. Approximately 80% of all glass fibers are used in this way. 

Sheet molding compound (SMC) is comprised of a thermosetting polyester/styrene matrix with fiberglass and CaCOs reinforcement. SMC is a major volume thermoset and comprises a large waste product stream after its intended use cycle. Two methods were evaluated for reinforcement of PP ... 

Positive high density parts involving composite Sheet Molding Compounds (SMC), Bulk Molding Compounds (BMC) or impact-thermosetting materials. 

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