THE STRUCTURE OF IN-SITU FORMED PAA-PVA C US NANOCOMPOSITIONS/

Structure of the PAA-PVA/CuS nanocompositions and the mechanism of for mation and growth of particles of the disperse phase during reactions in situ in the bulk of swelled polymer matrices were studied by method s of X-ray diffraction and electron microscopy. The nanocompositions w ere obtained by the repeated treatment of polymer matrices with CuSO4 and Na2S solutions (the method of cycle treatment). The maximum conten t of CuS in the compositions was similar to 50 vol %. The formation of particles of the disperse phase involves the following processes in t he polymer matrix: (i) interaction of S2- ions with the coordination b ound Cu2+ ions and the appearance of primary single-crystalline partic les (4-6 nm), (ii) coagulation and coalescence of the primary particle s with the formation of Secondary single-crystalline (similar to 15 nm ) and polycrystalline I,articles (similar to 60-70 nm), and (iii) prec ipitation of Cu2+ and S2- ions onto the outer and inner surfaces of co agulated particles.