Fig. 3 shows thermogravimetry of APTMS modified SiO2 nanopheres.
There are two obvious weight loss peaks. Loss of adsorbed
water occurs before 100 C and oxidation and decomposition of
grafted APTMS starts 250 C with an approximate 10% of weigh loss.
These results indicate that about 10% APTMS of SiO2 mass has been
grafted on the surface of silica nanopheres.