TY - JOUR
T1 - Reaction kinetics of a polyurea reaction injection molding system
AU - Pannone, Mary C.
AU - Macosko, Chris
PY - 1988/5
Y1 - 1988/5
N2 - Polyureas have the potential for Improving reaction Injection molding (RIM) productivity through shorter demo Id times and elimination of external mold release agents and post‐cure. Kinetics of urea formation are necessary for process modeling of polyurea RIM systems. Adiabatic temperature rise measurements were used to monitor the extent of reaction of an aliphatic diamine and an aromatic diamine reacting competitively with a single diisocyanate. The aliphatic diamine reacted much faster; essentially complete polymerization occurred in the RIM mixhead. A similar three‐component system was studied in dimethylacetamide and diethylene glycol dimethyl ether, and the sequential nature of the two competing reactions was confirmed. The RIM polymerization of the aromatic diamine, 3,5 diethyltoluene (2,4 and 2,6) diamine and;4,4′‐diphenylmethane diisocyanate was studied using an unreactive poly ether as the solvent. The exotherms could be fit with a third order model. Adiabatic temperature rises for all RIM experiments were in good agreement with the values predicted by heats of reaction measured in solution.
AB - Polyureas have the potential for Improving reaction Injection molding (RIM) productivity through shorter demo Id times and elimination of external mold release agents and post‐cure. Kinetics of urea formation are necessary for process modeling of polyurea RIM systems. Adiabatic temperature rise measurements were used to monitor the extent of reaction of an aliphatic diamine and an aromatic diamine reacting competitively with a single diisocyanate. The aliphatic diamine reacted much faster; essentially complete polymerization occurred in the RIM mixhead. A similar three‐component system was studied in dimethylacetamide and diethylene glycol dimethyl ether, and the sequential nature of the two competing reactions was confirmed. The RIM polymerization of the aromatic diamine, 3,5 diethyltoluene (2,4 and 2,6) diamine and;4,4′‐diphenylmethane diisocyanate was studied using an unreactive poly ether as the solvent. The exotherms could be fit with a third order model. Adiabatic temperature rises for all RIM experiments were in good agreement with the values predicted by heats of reaction measured in solution.
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U2 - 10.1002/pen.760281005
DO - 10.1002/pen.760281005
M3 - Article
AN - SCOPUS:0024016855
SN - 0032-3888
VL - 28
SP - 660
EP - 669
JO - Polymer Engineering & Science
JF - Polymer Engineering & Science
IS - 10
ER -