In this work, the cure kinetics of the uncatalyzed dicyanate ester monomer is studied using Fourier transform infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC). The cure kinetics are determined from FTIR studies at isothermal cure temperatures from 190 to 210°C. The kinetic model is tested by its ability to describe experimental DSC data over a wider temperature range (from 120 to 200°C). Tg is used as a direct measure of conversion in the DSC work, rather than using the conversion obtained by the residual heat of the reaction because Tg is more sensitive and more accurately measured. The relationship between Tg and conversion is further evaluated. From FTIR cure studies at five temperatures from 190 to 220°C, the reaction is found to proceed simultaneously via second order and second order autocatalyzed mechanisms. The second order reaction is presumed to be catalyzed by trace aryl phenol impurities. Experimental curves are fit by the rate expression throughout the entire range of cure. Experimental DSC Tg versus ln time curves are fit well for the cure temperatures studied (120 - 200°C) throughout the entire range of cure. Calculations were based on the proposed model and the rate constants and activation energies used were those obtained from the FTIR studies. It is concluded that the proposed model satisfactorily describes the experimental data land is a useful model of the reaction.
|Number of pages||5|
|State||Published - 1991|
|Event||49th Annual Technical Conference -ANTEC '91 - Montreal, Que, Can|
Duration: May 5 1991 → May 9 1991
|Conference||49th Annual Technical Conference -ANTEC '91|
|City||Montreal, Que, Can|
|Period||05/5/91 → 05/9/91|