This reaction is often facilitated by catalysts, such as or organometallic compounds (e.g., dibutyltin dilaurate). To create a solid foam, a "blowing agent" is added; commonly, water reacts with isocyanate to produce CO2CO sub 2 gas, which expands the polymer into a cellular structure. 2. Structure-Property Relationships
R−NCO+R′−OH→R−NH−CO−O−R′cap R minus NCO plus cap R prime minus OH right arrow cap R minus NH minus CO minus O minus cap R prime Polyurethane
Used in seating for comfort, bumpers for impact resistance, and coatings for corrosion protection and aesthetics. This reaction is often facilitated by catalysts, such
Long, flexible polyol chains that provide elasticity and low-temperature flexibility. such as or organometallic compounds (e.g.