ROSS INLINE MIXING SYSTEM EFFECTIVELY DISSOLVES UREA INTO POLYOL FOR RIM APPLICATIONS
Reaction Injection Molding or RIM, is a process where streams of Polyol and Isocyanate are brought together just prior to the inlet of an injection mold. The Polyol and Isocyanate react immediately to form a rigid Polyurethane or Polyurea part. One drawback to conventional RIM parts is their relative flammability. Several chemical companies have been working on RIM modifiers to make these materials less likely to burn. One such modifier is a Urea based material which increases the flame retardancy of RIM formulations. The only limitation to the use of the Urea is its difficulty in being dissolved and incorporated into the Polyol. The Urea is produced in pellet form and it can also be ground into a fine powder. Through extensive testing of the different Urea forms, it was concluded that the best method for incorporating the Urea into the viscous Polyol was by using a Ross Inline Rotor Stator Mixer combined with a recirculation vessel.