AUTOACCELERATION AND INHIBITION - FREE-VOLUME - EPOXY-AMINE KINETICS

The epoxy-diamine cure process was studied. We found that the mechanis m can be described in three steps: i) initiation up to 20-25% of conve rsion. ii) autoacceleration and iii) inhibition. It has been observed that after the initiation there is a clear autoacceleration effect whi ch has been explained in terms of free volume, considerations: the vol ume occupied by the products of reaction diminishes the available volu me increasing the ''local concentration'' of the reactants and therefo re the rate of reaction. The reaction was followed by FTIR(near infrar ed) as the main technique. We used a purified epoxy resin as well as p henyl glycidyl ether cured with m-xylenediamine. (C) 1998 John Wiley & Sons, Inc.