Nylon system equipment requirements

Equipment used to manufacture RIM products must be extensively rebuilt to process RIM nylons. Because the viscosity of nylon RIM systems is low and the ingredients are quite reactive, leakage at the seals and the volumetric efficiency of the metering pumps (that is, the amount of material actually pumped divided by the volume displaced by the metering pumps) may cause problems, which require special attention. Hence, most manufacturers recommend having the machine designed specifically for nylon RIM systems. 

Presence of fillers in material. These can greatly change the properties of the base resin which they occur in. For example, the presence of carbon black in polyethylene can turn a resin, which is normally nonhygroscopic, into one which is very moisture sensitive. The addition of glass fillers in the range of 30 to 40% turns nylon from a nonabrasive to an extremely abrasive material, thus requiring very careful selection of equipment and system elements. 

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