PMMA-based composite materials with reactive ceramic fillers .1. Chemical modification and characterisation of ceramic particles

Polymerisable organic silane molecules [3-(trimethoxysilyl)propyl methacrylate, gamma-MPS] have been grafted onto the surface of ceramic oxide powders (Al2O3, ZrO2, TiO2), via hydroxy groups of the latter oxides, in order to obtain organic-inorganic hybrid 'macromonomers'. Densities of surface hydroxy groups have been determined using thermogravimetry (TG) and chemical titration. Quantification of gamma-MPS grafting has been determined by FTIR spectroscopy, elemental analysis and TG. Typical grafting yields up to 6 mu mol m(-2) were obtained. The influence of the relative amount of silane used has been studied. Silane multilayers and/or aggregates are formed as observed in Si-29 CP MAS NMR spectroscopy.