A specially designed injection system was made to simulate the SRIM process. The isocyanate resin is put into one chamber and the polyol mixture is put into another chamber, and during processing, the liquids are combined together in a static mixer and injected into the mold. Preliminary trials with the Dow system and the Bayer system were very encouraging. Flow visualization experiments have been carried out with non-reacting fluids to simulate the hydrodynamic loads experienced by the single fiber in each mold cavity. The fibers survived high speed injections, indicating that dog bone samples can be prepared in a rapid injection and cure process.
Preliminary results indicate changing the gel time changes the measured interfacial properties.
Found that specimens using polyisocyanurate as a matrix had an interfacial shear strength that was independent of testing speed. Previously tested specimens with epoxy as the matrix had interfacial shear strengths that were rate dependent.