Synthesis and characterization of a soluble ladderlike polysilsesquioxane containing reactive ester groups

A novel soluble ladderlike polysilsesquioxane containing reactive ester gro ups (Ester-T) was synthesized for the first time by stepwise coupling polym erization including preammonolysis, controlled hydrolysis and polycondensat ion. The monomer, 3-trichlorosilylpropoxy 4-acetoxybenzoate (M), was synthe sized by hydrosilylation of allyloxy 4-acetoxybenzoate with trichlorosilane in the presence of dicyclopentadienylplatinum (II) chloride (Cp2PtCl2) cat alyst. Combination of FTIR, H-1-NMR, C-13-NMR, Si-29-NMR, XRD, DSC, TGA and VPO methods was used to demonstrate that the polymer obtained has an order ed ladderlike structure. The synthesized Ester-T may have promising applica tions as a precursor of advanced functional polymers.