1999 Volume 72 Issue 2 Pages 66-73
The kinetics of the model reaction during phenyl isocyanate, n-butanol, and polymer alcohol at 65°C under the absence and presence of catalysts were investigated. Effects of the catalysts on hard segment distribution and mechanical properties of polyesterurethane elastomers were also studied. Catalysts used were dibutyltin dilaurate (DBTL) and 1, 4-diazabicyclo-(2, 2, 2) octane (DABCO). Polyurethanes were prepared from poly (ethylene adipate) (PEA), TDI, and 1, 4-butanediol (BD) by one-shot method. From the results of kinetic study by using GPC, it is suggested that DABCO accelerates the urethane and allophanate formation and DBTL more urethane than allophanate formation in bulk polymerization. The PUEs prepared under presence of the catalysts contained more trimer [-(TDI- BD)3-] than the PUEs under absence of catalysts. Hard segment length of PUEs prepared under the presence of DABCO have longer than other PUEs. Mechanical properties of the PUEs affected by a kind of catalyst used.
