Synthesis and characterization of 3-(2,3-dihydroxypropoxy)propyl-terminated polydimethylsiloxanes

3‐(2,3‐Dihydroxypropoxy)propyl‐terminated polydimethylsiloxanes (DHT‐PDMS) samples were prepared through the copolymerization of 1,1,3,3,5,5,7,7‐octamethylcyclotetrasiloxane (D4) and 1,3‐bis[3‐(2,3‐dihydroxypropoxy)propyl]‐1,1,3,3‐tetramethyldisiloxane by acid‐catalyzed equilibration. Their structures were characterized with IR and 1H‐NMR spectra. The molecular weights were determined with gel permeation chromatography and 1H‐NMR spectra, respectively. Differential scanning calorimetry and thermogravimetric analysis were used to investigate the thermodynamic properties and thermal degradation of DHT‐PDMS. The effects of various factors on the synthesis of DHT‐PDMS were also examined. However, the preparation of DHT‐PDMS through the base‐catalyzed equilibrium copolymerization of D4 and 1,3‐bis[3‐(2,3‐epoxypropoxy)propyl]‐1,1,3,3‐tetramethyldisiloxane, followed by the hydrolysis of the epoxy groups, was unsuccessful. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 110–115, 2004