A Simple Karl Fischer Titration Procedure for Determination of Total Hydroxyl Content in Silanol-Terminated Polvsiloxanes

This paper describes a simple procedure for the determination of total hydroxyl content in simple silanols and silanol-terminated polysiloxanes. The proposed procedure is based on a conventional pyridine-free Karl Fischer titration method. A temperature of 50°C is used to accelerate and complete the reaction between the KF reagent and silanol (SiOH) groups. Validation shows that the procedure is precise and accurate. Typical relative standard deviation of the procedure is 1-2%. When compared to a routine FTIR method, the Karl Fischer titration procedure produced similar quantitative results, but was superior in terms of simplicity in equipment and standardization.