摘要 |
An externally heated reaction injection molding ("RIM") system and processes for producing polyurethane articles. The system comprises a mixing chamber for combining a prepolymer and a chain extender and one or more heating systems for heating at least one of the prepolymer and the chain extender upstream of the mixing chamber. In one embodiment, the process comprises injecting a heated prepolymer and/or a heated chain extender into a mixing chamber and initiating a curing of the prepoiyrner in a mixing chamber. By employing heat to decrease the viscosity of the prepolymer and/or the chain extender, prepolymers and/or chain extenders that have high room temperature viscosities or are in the solid state at room temperature, may be utilized in the RlM system.
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