Photoacoustic Fourier transform infrared (PA FT-IR) spectroscopic measurements were performed in order to study the interaction between the surface of SiO
2 and poly (dimethyl siloxane) (PDMS). Since larger surface area increases the PA signal of the interface, silica gel with a surface area of 662 m
2g
-1 was used as an adsorbent for PDMS. A PA signal at 3737 cm
-1 due to the isolated silanol groups on the surface of silica gel disappeared on addition of PDMS. On the other hand, another signal at 3647 cm
-1 due to the silanol groups participating in hydrogen bonds with water molecules was invarient.
These results suggested that only the isolated silanol groups on the surface of silica gel formed hydrogen bonds to oxygen atoms of PDMS chain.
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