Synthesis and thermal stability of star polymer with eight arms using polyhedral oligomeric silsesquioxane as a core
AbstractA Polyhedral oligomeric silsesquioxane (POSS) containing eight 3- chloropropyl groups was synthesized and incorporated into poly(methyl methacrylates) to form star polymer. First, octa(3-chloropropyl) POSS [(ClCH2CH2CH2)8Si8O12] was prepared by hydrolysis and condensation of 3- chloropropyltriethoxysilane, and then two star-shaped POSS/PMMA composites with different POSS content was synthesized at 110 °C, using octa(3-chloropropyl) POSS as an multifunctional initiator, CuCl and 2-2’ bipyridine (Bpy) as catalyst system. The structures of octa(3-chloropropyl) POSS and star-shaped POSS/PMMA composite were characterized by analytical methods including FTIR, NMR, GPC and XRD, with results showing that POSS molecule was successfully formed which accorded well with the reported work and was dispersed into PMMA matrix evenly by atom transfer radical polymerization method. The TGA results indicated that synthetic POSS molecule possessed good thermal stability, and the thermal stability of POSS/PMMA composite enhanced with the increase of POSS content, which is due to the incorporation of inorganic POSS molecule