An alumina hydrosol is synthesized by controlled hydrolysis of an aqueous s
olution of aluminium chloride using the thermal decomposition of urea. Afte
r dialysis, a transparent and fluid colloidal dispersion is obtained which
can be used to prepare alumina coatings. The characteristics of the sol, th
e structure and the thermal evolution of the resulting alumina gels are stu
died. (C) 1999 Elsevier Science B.V. All rights reserved.