Molding compounds low pressure

Low pressure molding compound (LPMC) is an SMC kind of material. TMPC is made by replacing the chemical thickening mechanism with a physical thickening mechanism using crystic polyester. The material is first... 

LCD lowest common denominator LMC low-pressure molding compound... 

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

Low-cost molds for contact and low-pressure molding can be made from reinforced TS polyester or epoxy compounds with glass fiber and/ or mineral filler reinforcement. These constructions have also been used to make prototype molds for compression and injection molding, with the advantages that they can be produced quickly and at low cost (often in-house) and can readily be modified. Latest technology uses blocks of resin-based compounds that can be machined by computerized instructions, for production of protot5 e molds. 

Low-Pressure Molding. The distribution of relatively uniform low pressure (200 psi or less) over a glass-reinforced thermoplastic compound, with or without application of heat from external source, to form a structure possessing definite physical properties. 

Thermoset molding compounds, when contained within a hardened steel mold, require heat and pressure to be polymerized into a solid mass. Molds may be heated by steam, electricity, or hot oil to temperatures of 280° to 425°F, depending entirely on the type of material and method of molding. Molding pressures may vary from a low of 50 p.s.i. to 15,000 p.s.i. Epoxy materials will mold at 50 p.s.i. whereas, phenolic fabric-filled material may require excessive pressures. Again, the method of molding dictates molding pressures. 

ASTMD3123, Thermosetting Molding Compounds, Spiral Flow, Low Pressure, Vol. 8.02, ASTM, Philadelphia, Pa., 1994. 

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