In this communication we show that an AT-cut quartz crystal analyser (
QCA) can be applied to the investigation of the phase transition of po
lymer blend thin films. The phase transition phenomena of blend films
of poly(methyl methacrylate) (PMMA) and poly(vinyl acetate) (PVAc) hav
e been elucidated by simultaneous measurement of the resonant frequenc
y and resonant admittance of the QCA. The PMMA/PVAc blend cast from et
hyl acetate exhibited critical changes of resonant frequency and reson
ant admittance at the glass transition point. Copyright (C) 1996 Elsev
ier Science Ltd.