Application of thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) to estimate the normal boiling points of ∆9-tetrahydrocannabivarin (THCV) and ∆9-tetrahydrocannabinol (THC)

Physical properties, particularly boiling point and heat of vaporization are important when designing cannabinoid purification strategies based on distillation methods and when engineering vaporization-based cannabinoid delivery commercial products. Cannabinoid standards were obtained from Sigma-Aldrich. Concentrates of ∆9-tetrahydrocannabivarin (THCV), Δ9-tetrahydrocannabinol (THC), and THCV-THC mixtures were obtained from Schwazze Biosciences. Thermogravimetric Analysis (TGA) and Differential Scanning Calorimetry (DSC) were used to determine boiling points and estimate heats of vaporization (ΔHvap). Based on combined TGA and DSC data and the Sydney-Young equation, the 95% confidence interval for THCV normal boiling point was 378 ± 4 °C. The 95% confidence interval for THC normal boiling point was 245 ± 6 °C. Experimental values for boiling point were significantly different from the values commonly reported for both compounds in commonly referenced sources. The values in popular literature and websites are often not referenced and do not indicate pressures for reported boiling points.