Unlike thermoplastic injection molding, Reaction Injection Molding is a process capable of achieving a broad range of properties. While both processes use molds to form parts, the RIM process uses polyurethanes to produce molded parts.

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The RIM Process

The polyurethanes are two liquid components (Polyol and Isocyanate) developed in two-part formulations to create RIM systems. The system will determine whether the part molded will be a foam or a solid and whether the part will be flexible or extremely rigid. The specific gravity will range from 0.2 to 1.6.

The RIM Process involves a chemical reaction between the two liquid components. Initially, the liquids are held in separate, temperature-controlled feed tanks. The chemicals are fed through supply lines to metering units that precisely meter both chemicals, at high pressure, to a mixhead device.

Typical Systems Used by RIM Manufacturing 

RIM Manufacturing uses numerous polyurethane systems in the manufacturing of parts.  The system used depends on a variety of factors such as: use, strength, durability, density, wall thickness, flammability, load factor, etc.  Click on the schedule below to view some of the technical properties for some of the basic chemical systems used by RIM Manufacturing.

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