Abstract: An elongated electrically insulating support structure, for use by itself as an electrical insulator or for use as a strength member in a composite electrical insulator made of fiberglass-reinforced resin, comprising a central cylindrical body and ends having the shape of solids with surfaces of revolution with axial symmetry, having diameters larger than the diameter of the central cylindrical body, with which they are radiused without solution of continuity, i.e., connected without and discontinuity, wherein the central cylindrical body and the ends consist of superimposed and crossed layers of glass filament impregnated with thermosetting resin, wound around a cylindrical element with a helical winding angle smaller than 90.degree..

Abstract: Glass having improved hydrolytic and chemical resistance as well as improved water repellency and mechanical characteristics is obtained by reacting the glass surface with an organoborosiloxane polymer, substituted by one or more of alkyl, aryl, alkoxy, acyl radicals, said organoborosiloxane polymer containing no free hydroxy groups in the presence of one or more organic Ti, Zr, Sn, v compounds at a temperature comprised between 200.degree. and 400.degree.C in order to obtain, through a grafting reaction, a superficial layer of modified glass.