Silica/epoxy hybrid polymers were synthesised from 3-glycidoxypropyltrimethoxysilane (GPTMS) by hydrolysis of the silane functional groups in strongly acidic (pH 2) or basic (pH 10) conditions, followed by epoxy ring opening and crosslinking using diethylamine triamine (DETA) and ethylene diamine (EDA). Structural characterization of the hybrid polymers was performed using FTIR spectroscopy. The thermal properties of GPTMS/DETA and GPTMS/EDA hybrid polymers were investigated by differential scanning calorimeity and thermogravimetric analysis, while thermomechanical properties were measured using dynamic mechanical thermal analysis. The influence of pH on the structure and properties of the synthesised GPTMS/DETA and GPTMS/EDA hybrids is discussed. (c) 2007 Elsevier B.V. All rights reserved.