PPDI Prepolymer Synthesis and Chain Extension

This is the same as that of CHDI except that using PPDI requires a higher temperature (70-80°C) to dissolve in polyols, and, importantly, the use of a catalyst to promote the chain extension reaction is both unnecessary and 

EFFECT OF TEMPERATURE ON THE PROPERTIES OF PPDI AND CHDI POLYURETHANE 

Diisocyanate/polyol mole ratio 2 1 Chain extended with 1,4-butanediol 

Chain-extended with Dianol 22, a bis ethylene oxide adduct of bisphenol A and a trade name of Akzo Chemie, bv. 

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