Crystallization of a Cyanurate Trimer in Nanopores

Nanoconfinement is known to depress the melting temperature through the well-known Gibbs-Thompson equation. Less well studied is the influence of nanoconfinement on crystallization kinetics. In this work we investigate crystallization of a cyanurate trimer using differential scanning calorimetry. The material shows cold crystallization and melting in the bulk state. Under the nanoconfinement of controlled pore glasses (CPG), cold crystallization and melting shift to lower temperatures, following the shift in the glass transition temperature. More importantly, however, the crystallization kinetics slow down and no crystallization occurs in 13 nm-diameter pores. Isothermal crystallization studies indicate that the Avrami exponent is approximately 2.0 for both bulk and nanoconfined samples. The time scale for crystallization is over one order of magnitude longer for samples confined in 50-nm pores in spite of the fact that samples were crystallized the same distance from T$_{g}$.