2015 Volume 51 Issue 2 Pages 42-48
The improvement of thermal stability of 3-glycidoxypropylmethyldimethoxysilane by the reaction with silica particle surface and polycondensation was investigated using thermogravimetric（TG） analysis. The temperature of 50％ weight loss for polycondensed silane was remarkably higher than that for monomeric silane. The TG curve for surface treated silica showed weight loss with three steps:100-150℃（1st step）, 150-250℃（2nd step）and 250-350℃（3rd step）. The weight loss in 1st step decreased, whereas those in 2nd and 3rd steps increased by heating of treated particles. The weight losses in three steps were based on the physically adsorbed monomeric silane（1st step）, the physically adsorbed polycondensed silane（2nd step）and the chemically adsorbed silane（3rd step）. The physically adsorbed percent in the silane treated layer measured from the TG curve for the treated silica without washing was almost equal to that measured from the comparison of weight losses for before and after acetone w ashing to remove the physically adsorbed molecules. It was clarified that the physically adsorbed percent can be measured from the TG curve for treated particles without washing.
