Kinetic parameters of a cyanate ester resin catalyzed with different proportions of nonylphenol and cobalt acetylacetonate catalyst

Catalytic effects of copper oxides on the curing and degradation reactions of cyanate ester resin

“…The high temperature exothermic shoulder is usually observed and attributed to the competing autocatalytic reaction in uncatalyzed CE resins. 37,39,41 The results here confirm the presence of small amounts of not catalyzed resins in the copper oxides catalyzed specimens.…”

“…Also shown in Figure 3, the peak temperatures (T p ) of curing exotherms are 174, 223, 225, and 2678C for zinc octoate, cuprous oxide, cupric oxide added systems, and the uncatalyzed resin, respectively; since a lower peak temperature of the curing exotherm is usually indication of a higher reaction rate and sometimes a smaller activation energy of cure which are obtained in many metal salt catalyzed cyanate systems. 36,37 The difference obtained in T p also confirms the significant catalytic effects of two copper oxides during the cure.…”

“…The shouldering exothermic peak is usually obtained in many metal salt catalyzed cyanate ester systems, which is attributed to the multiple/ parallel reaction mechanisms during the cure and the possible formation of active catalytic species or imidocarbonate intermediate. [37][38][39][40][41] As indicated, the width between the shoulder and the maximal peak is different among three catalyzed resins and increases in the order of zinc octoate < cupric oxide < cuprous oxide. This implies that a difference in the catalytic effect would affect the succeeding catalytic reaction (represented by T p of the main peak) and the zinc octoate has a much better overall accelerating effect than two copper oxides.…”

“…It have been demonstrated in other studies that the formation of intermediate by-products during cyclotrimerization could be promoted and the reaction order of the CE be changed by adding the catalysts. 37,39,42,43 A further study on explaining these differences would be needed.…”

Acceleration effect of ionic liquids on polycyclotrimerization of dicyanate esters

“…In contrast, reports on ILs involved in crosslinking processes are much scarcer [13]. The curing kinetics of neat CERs has extensively been reported in the literature [14][15][16][17][18][19][20][21]. It is of common knowledge that the polycyclotrimerization of dicyanate esters is rather slow, and it generally requires the presence of a curing catalyst which may be either a Lewis acids or acetylacetonates of Cu 2+ , Co 3+ , Zn 2+ and Mn 2+ [22], or a chelate in the presence of an active hydrogen-containing co-catalyst (such as nonylphenol), acting as a source of proton.…”