Structure and Properties of PVA/SiO ₂ Interpenetrating Polymer Network Materials Prepared by the Sol–Gel Method

Organic–inorganic interpenetrating polymer network (IPN) materials were prepared by hydrolysis and condensation of tetraethoxysilane (TEOS) in poly(vinyl alcohol) (PVA) solution. The structure and morphology of the IPNs were investigated by infrared spectroscopy (FTIR) and transmission electron microscopy (TEM). The thermal properties were examined by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). FTIR spectroscopy showed the formation of Si–O–C and Si–O–Si bonds in the system. TEM demonstrated a homogeneous dispersion of silica in the PVA matrix when the amount of TEOS added was appropriate. DSC and TGA revealed that, compared with pure PVA films, the hybrid films exhibited a higher glass transition temperature (T _g ) and high thermal stability.