Phosphorylated polymers are versatile materials for a broad range of applications from flame-retardant coatings to bioactive scaffolds. Traditionally, they are synthesized in solution using corrosive concentrated phosphoric acid and energy-intensive drying techniques. In the past decade, mechanochemistry has proven to be a valuable tool for green chemists to conduct new transformations, with minimal waste, often solvent-free. This work presents the phosphorylation of cellulose nanocrystals, poly­(ethylene glycol), poly­(vinyl alcohol), poly­(vinyl chloride), and lignin through mechanochemical processes with phosphorus pentoxide to produce reproducible phosphorylation for potential flame-retardant applications. Through 31P magic angle spinning (MAS) NMR, loadings of up to 3300 mmol/kg were determined for cellulose nanocrystals, far superior to loadings in solution around 1600 mmol/kg, and loadings of up to 4375 mmol/kg were obtained for synthetic polymers such as poly­(vinyl alcohol).

Dedicated to Dr. Terrence "Terry" Fiss who sadly passed away after a long battle with cancer during the preparation of this manuscript. Uncle Terry had always been one of my strongest supporters in my pursuit towards a career in science, always encouraging me to tackle tough problems, and never stop asking questions.

For inorganic metathesis and reduction reactivity, mechanochemistry is demonstrating great promise towards both nanoparticles and organometallics syntheses.