Polymerization kinetics of adamantane-based dicyanate ester and thermal properties of resulting polymer

Abstract

The kinetics of liquid-state polymerization of adamantane-based dicyanate ester has been studied for the first time by means of conventional and temperature-modulated DSC. It has been detected that the later stages of polymerization undergo a transition from kinetic- to diffusion-controlled regime. Detailed analysis of the polymerization kinetics in the reaction-controlled regime has revealed that the process rate can be well described in the frameworks of the presently proposed autocatalytic quasi-one-step model. The proposed model eliminates arbitrarily guessing the value for the initial conversion that provides a reasonable alternative to the broadly used truncated Sestak-Berggren model. The adamantane-based dicyanate ester polymerization product demonstrates markedly higher thermal stability and glass transition temperature compared to those of dicyanate esters with flexible hydrocarbon bridging units. The obtained experimental results confirm our hypothesis about the influence of the rigidity of cyanate ester molecule on its reactivity and thermal properties of the corresponding polymer product.