Horizontal znse crystal

The degree of conversion of the experimental materials was evaluated using Fourier transform infrared spectroscopy with a spectrometer (Prestige 21, Shimadzu, Ltd., Tokyo, Japan) equipped with an attenuated total reflectance device. The reflectance device was composed of a horizontal ZnSe crystal with a 45° mirror angle (PIKE Technologies, Madison, WI, USA). The IRSolution software package (Shimadzu, Columbia, MD, USA) was used in the monitoring scan mode using Happ–Genzel apodization in the range 1750–1550 cm⁻¹ range, an 8 cm⁻¹ resolution and 2.8 mm/s mirror speed. Using this configuration, one scan was acquired every 1 s during light activation. The degree of conversion was calculated as described in a previous study¹⁹ and based on the intensity of the carbon–carbon double-bond stretching vibrations (peak height) at 1635 cm⁻¹, as well as using the symmetric ring stretching at 1610 m⁻¹ from the polymerized and non-polymerized samples as an internal standard. The analyses were performed in triplicate (n=3). The data were plotted and curve fitting was applied using logistic non-linear regression. In addition, the polymerization rate (Pr^-1) was calculated as the degree of conversion at time t subtracted from the degree of conversion at time t − 1. The coefficient of determination was greater than 0.98 for all curves.