a3-Glycidoxypropyltrimethoxysilane (0.69 g, 2.1 mmol) in THF (2 mL) was added to a mixture of poly(ethylene glycol)-bl-poly(propylene glycol)-bl-poly(ethylene glycol) (1 g,0.53 mmol, MW = 1900), zirconium(IV) chloride (20 mg) and THF (4 mL), and the solution stirred at 400 ...