| | Reaction Injection Molding RIM |
 | | Resistance to weathering and aging is another plus, though extended exposure to the sun’s ultraviolet rays typically results in a color shift at the surface. |
 | | When injection begins and valves in the mixhead open, the liquid reactants enter a chamber in the mixhead at pressures between 1,500 and 3,000 psi where they are intensively mixed by high-velocity impingement. |
 | | From the mix chamber, the liquid flows into the mold at approximately atmospheric pressure and undergoes an exothermic chemical reaction, forming the polyurethane polymer in the mold. |
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